A Reliable Method for Predicting the Specific Impulse of Chemical Propellants

ABSTRACT

The specific impulse (I_sp) is an important performance parameter that describes energy efficiency of propellant combustion and is intimately related to the rocket engine thrust. In this study, it was possible by using only two variables, i.e., the heat of reaction (Q) and the number of moles of gaseous reaction products per gram of propellant (N_g) calculated according to [H₂O-CO₂] arbitrary decomposition assumption and constants derived from the ISPBKW code to predict the specific impulse of more than 165 compositions belonging to virtually all classes of propellants such as monopropellants, single-base, double-base, triple-base, and cast modified double-base (CMDB) propellants, pseudo-propellants, composite propellants, liquid mono- and bipropellants, and finally hybrid propellants. Further analysis reveals that for C-H-N-O containing propellants, the specific impulse values estimated using the new method should not deviate more than 5% from the output of the ISPBKW thermochemical code.

KEYWORDS:
Specific impulse prediction; Solid propellants; Liquid propellants; Hybrid propellants; ISPBKW code

INTRODUCTION

The first propellant ever created was black powder or gunpowder, which consists of a physical mixture of saltpeter, charcoal and sulfur. For many centuries, this low energy composite mixture served as the sole energetic material for both military and civilian applications. The need for cleaner, more energetic propellants led to the invention of smokeless powder, a homogenous mixture of two well-known explosives substances: nitrocellulose (NC) and nitroglycerine (NG) (Klapötke 2011). For instance, a solid explosive like 2,4,6-Trinitrotoluene (TNT) will detonate when subject to a powerful shock wave but it will only burn or deflagrate when brought into contact with a flame, and hence it is not surprising that most of today's propellants formulations contain large quantities of explosive materials since the thermochemistry of both explosives and propellants is essentially the same (Kubota 2015) but they do differ in their rate of energy release which, to a large extent, depends on the nature and amplitude of the external stimuli that cause them to react in one way or another. Given the relatively long burning time from several seconds to several minutes and coupled with the generation of substantial amounts of hot gaseous products, chemical propellants, whether in solid or liquid state are the principle source of the propulsive force that accelerates rockets, guided missiles and artillery shells. The thrust that a rocket motor develops is directly linked to the specific impulse (I_sp) defined as the thrust delivered per unit flow weight of propellants consumed (Bourasseau 1990). Two commonly used units for (I_sp) are seconds (s) and Ns g^-1 (or Ns kg^-1). Achieving high (I_sp) values is always desirable especially in the case of long range missiles. It can be shown, that almost 45% gain in range can be realized by increasing only 5% the specific impulse of a typical intercontinental ballistic missile having an initial range of 5000 nautical miles (Thompson Jr. 1960).

More specifically, the rocket combustion chamber temperature (T_c) and the average molecular weight (M) of the exhaust gas are the primary dominant factors determining the specific impulse (Kinney 1960). Thus, the relationship relating (I_sp) to (T_c) and (M) is shown by:

(1) ${\mathit{I}}_{\mathit{sp}}\propto \sqrt{{\mathit{T}}_{\mathit{c}}/\stackrel{─}{\mathit{M}}}$

As Eq. 1 states, this highest (I_sp) value can be reached by finding a propellant formulation capable of generating the highest (T_c) and the lowest possible (M). However, during rocket operation, the combustion chamber walls may be weakened due to the large heat transfer from the burning propellant, which can ultimately lead to a catastrophic structural failure; therefore combustion temperature should be kept at an acceptable level without sacrificing overall performance. Another problem facing propellant formulators is the difficulty encountered in the experimental evaluation of the specific impulse that requires hundreds of kilograms of potentially dangerous and explosives energetic materials (Bhat et al. 1988; Lempert et al. 2011). Consequently, researchers rely heavily on thermochemical code such as NASA CEA (Gordon and McBride 1996) or TERRA code (Trusov 2002) to accurately compute propellant performance at a determined pressure ratio defined as (P_c: P_a) where (P_c) and (P_a) are the combustion chamber pressure and the ambient pressure at the nozzle exit, respectively. Similarly to thermochemical codes, relationships derived from empirical data present a viable alternative to compute the performance of explosives and propellants. Recent studies show that condensed explosive detonation velocity (Keshavarz 2012), pressure (Keshavarz et al. 2014), temperature (Keshavarz and Nazari 2006) and other performance parameters (Frem 2017), as well as the specific impulse of monopropellants (Frem 2016), can be precisely calculated using only few experimental data (e.g. crystal density, heat of formation, etc.) and no more than a hand-held calculator. Accordingly, the intent of the next section is to present a detailed derivation of a new and simple method for predicting the specific impulse of C-H-N-O chemical propellants that do not contain any metal additives such as aluminum.

RESULT AND DISCUSSION

NEW RELATIONSHIP FOR THE ESTIMATION OF THE SPECIFIC IMPULSE (I_SP)

The driving force behind the current study was the work of Kamlet & Jacobs (K-J) published in 1968 (Kamlet and Jacobs 1968), where the authors have showed that the detonation velocity (D) and pressure (P) for C-H-N-O containing explosives can be predicted following Eqs. 2 and 3:

(2) $\mathit{D}\left(\mathit{mm}\mathit{\mu }{\mathit{s}}^{-1}\right)=\mathit{A}{\mathit{\Phi }}^{0.5}\left(1+\mathit{B}{\mathit{\rho }}_0\right)$

(3) $\mathit{P}\left(\mathit{kbar}\right)=\mathit{K}{\mathit{\rho }}_0^2\mathit{\Phi }$

where: ρ₀ (g·cm^-3) is the explosive initial density; A, B, K are constants and equal to 1.01, 1.30, and 15.58, respectively, while; (N_g) is the number of moles of gaseous detonation products per gram of explosive; (M_g) is the average molecular weight of these gases; and (Q) is the heat of detonation in (cal·g^-1). The (K-J) method presumes that for C-H-N-O explosives at an initial ρ₀ = 1.7 - 1.9 g·cm^-3, the major decomposition products are water (H₂O), carbon dioxide (CO₂) and nitrogen (N₂), and often termed the [H₂O-CO₂] arbitrary decomposition assumption. Despite its simplicity, the detonation velocity and pressure calculated using the [H₂O-CO₂] arbitrary are in good agreement with the value obtained using complex thermochemical codes. The (Φ) parameter was later used to obtain the Gurney velocity (√2E_G) (Hardesty and Kennedy 1977; Kamlet and Finger 1979), an important performance parameter that represents the ability of a given explosive to push and accelerate a surrounding metal shell. Given the fact that explosives and propellants possess comparable energy content and, in many cases similar chemical compositions, it was felt that the [H₂O-CO₂] arbitrary could, in principle, be used to estimate the specific impulse. To test this hypothesis, a thorough study was made in order to uncover the potential influence of (N_g), (M_g), and (Q) on specific impulse. The results show, that only (N_g) and (Q) were significant in obtaining a relationship capable of accurately predicting propellant (I_sp) (Eq. 4):

(4) ${\mathit{I}}_{\mathit{sp}}^2={\mathit{X}}_1+{\mathit{C}}_1\left({\mathit{N}}_{\mathit{g}}\right)+{\mathit{C}}_2\left(\mathit{Q}\right)$

where the intercept X₁ and the coefficient C₁ - C₂ were derived using a multiple linear regression analysis (MLRA) and the computed (I_sp) values for thirty-seven C-H-N-O monopropellants shown in Table 1 (Eq. 5):

(5) ${\mathit{I}}_{\mathit{sp}}\left(\mathit{Ns}{\mathit{g}}^{-1}\right)=\sqrt{-}4.459+121.81\left({\mathit{N}}_{\mathit{g}}\right)+4.697\left(\mathit{Q}\right)$

Table 1
Comparison between the specific impulse values calculated using the ISPBKW code and Eq. 5 for different monopropellant compositions. Percentage deviations in parentheses.

Compositions	∆Hºf (kcal mol–1)a	Ng	Q/ (kcal g–1)	Isp/(Ns g–1)c	Isp(Eq. 5)/(Ns g–1)d
PETN	–128.7	0.0316	1.514	2.58	2.55 (–1.23%)
TNT	–16.0	0.0253	1.291	2.11	2.17 (2.62%)
HMX	17.93	0.0338	1.477	2.62	2.57 (–1.86%)
RDX	14.71	0.0338	1.482	2.62	2.57 (–1.81%)
Tetryl	4.67	0.0270	1.420	2.35	2.35 (0)
NM	–27.0	0.0369	1.364	2.46	2.54 (3.23%)
HNS	18.7	0.0233	1.367	2.19	2.19 (0%)
Comp-B	1.28	0.0308	1.410	2.42	2.43 (0.52%)
PBX-9404	0.08	0.0337	1.414	2.55	2.51 (–1.90%)
PBX-9011	–4.05	0.0333	1.358	2.43	2.44 (0.59%)
LX-14	1.5	0.0336	1.423	2.54	2.51 (–1.04%)
Pentolite (50/50)	–23.9	0.0285	1.402	2.37	2.37 (0)
HNAB	67.9	0.0243	1.445	2.32	2.30 (–0.92%)
NG	–88.6	0.0319	1.591	2.53	2.63 (3.67%)
NQ	–22.1	0.0385	0.898	2.11	2.11 (0)
Octol (75/25)	2.78	0.0317	1.431	2.50	2.47 (–0.95%)
TATB	–36.85	0.0291	1.075	2.01	2.03 (1.26%)
PA	–51.3	0.0251	1.283	2.18	2.15 (–1.47%)
Cyclotol (60/40)	1.15	0.0304	1.406	2.42	2.42 (0)
DEGDN	–99.4b	0.0332	1.392	2.42	2.47 (2.20%)
PBX-9007	7.13	0.0324	1.392	2.39	2.46 (2.83%)
PBX-9501	2.28	0.0336	1.442	2.56	2.53 (–1.29%)
DIPAM	–6.80	0.0253	1.298	2.16	2.17 (0.49%)
BTNEU	–76.91b	0.0311	1.467	2.52	2.49 (–0.89%)
BTTN	–97.04b	0.0322	1.509	2.59	2.56 (–1.18%)
FOX-7	–32.00b	0.0338	1.199	2.38	2.30 (–3.40%)
DDNP	46.39b	0.0238	1.391	2.27	2.23 (–1.93%)
DNDMOxm	–73.00b	0.0316	1.171	2.22	2.21 (–0.26%)
DNOC	–47.80b	0.0253	1.109	1.93	1.96 (1.34%)
DNPH	11.95b	0.0278	1.173	2.07	2.11 (1.87%)
DINA	–65.88b	0.0333	1.472	2.56	2.55 (–0.44%)
DIPEHN	–233.79b	0.0315	1.422	2.49	2.46 (–1.03%)
ETN	–114.76b	0.0325	1.365	2.34	2.43 (4.02%)
EDDN	–156.18b	0.0403	0.966	2.20	2.23 (1.49%)
EDNA	–24.81b	0.0367	1.303	2.46	2.48 (0.69%)
GUNI	–92.52b	0.0410	0.662	1.90	1.91 (0.31%)
FOX-12	–85.09b	0.0371	0.898	2.15	2.07 (–3.95%)

• ^a
  Heat of formations (HOFs): (Dobratz and Crawford 1985) otherwise stated;
• ^b
  (Meyer et al. 2007);
• ^c
  Equilibrium specific impulses were calculated using the ISPBKW thermochemical code (Mader 2008);
• ^d
  To convert to the more conventional units of seconds, divide by 0.00981 Ng–1.

where (Q) and (N_g), now termed the heat of reaction in (kcal g^-1) and the number of moles of gaseous reaction products per gram of propellant, respectively, were calculated according to Eqs. 6 and 7:

(6) $\mathit{Q}=\frac{28.9\mathit{b}+47\left(\mathit{d}-\raisebox{1ex}{$\mathit{b}$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\right)+\Delta {\mathit{H}}_{\mathit{f}}^O}{{\mathit{M}}_{\mathit{w}}}$

(7) ${\mathit{N}}_{\mathit{g}}=\frac{2\mathit{c}+2\mathit{d}+\mathit{b}}{48\mathit{a}+4\mathit{b}+56\mathit{c}+64\mathit{d}}$

where: a, b, c and d are the number of carbon (C), hydrogen (H), nitrogen (N) and oxygen (O) atoms in the propellant composition, (ΔHº_f kcal mol^-1) represents the condensed phase heat of formation (HOF), and M_w is the composition's molecular weight. The calculated specific impulse of the training set was obtained using the ISPBKW thermochemical code (Mader 2008) at a predetermined chamber and nozzle exit pressure of 68.9 and 1 bar (P_c: P_a = 68.9:1), respectively. The coefficient of determination (R²) of the regression equation is equal to 0.948. Relevant statistical results (t-stat, P-values, regression coefficients C₁ - C₂, etc.) obtained from the (MLRA) are summarized in Table 2. The P-values < 0.05 and the t-values clearly indicate that the suggested independent variables are significant to estimate specific impulse. Moreover, the very small significance F value (1.45810^-22) confirms the validity of the regression output.

Table 2
Coefficients, standard errors, t-statistics, statistical significance (P-values), the lower and upper bounds of the 95% confidence intervals of Eq. 5 obtained by multiple regression analysis (R 2 adjusted = 0.945).

	Coefficients	Standard Error	t-Stat	P-value	Lower 95%	Upper 95%
Intercept	–4.459	0.437	–10.193	7.13 10–12	–5.348	–3.570
Ng	121.81	8.62	14.135	8.51 10–16	104.29	139.32
Q	4.697	0.193	24.328	4.36 10–23	4.305	5.090

It can be seen from Table 1 that there is a good agreement between the specific impulses calculated using the ISPBKW code and the values obtained by applying Eq. 5 and in all of the studied cases the deviation did not exceed ± 3 - 4%.

The intention of the next sections is to evaluate the predictive ability of the obtained model by using a test set comprising not only solid single component monopropellants, but also multicomponent solid, liquid, and hybrid propellants.

SINGLE MOLECULE MONOPROPELLANTS

The monopropellants shown in Fig. 1 were carefully chosen so as to cover the most important class of energetic molecules such as nitroaromatics, aliphatic nitrate esters and salts of high-nitrogen content heterocycles. Moreover, the specific impulses for the twenty studied structures were predicted using both Eqs. 5 and 8:

(8) $\begin{array}{c}{\mathit{I}}_{\mathit{sp}}\left(\mathit{Ns}{\mathit{g}}^{-1}\right)=2.4205-0.0740\mathit{a}-0.0036\mathit{b}+0.0237\mathit{c}+\\ +0.0400\mathit{d}-0.1001{\mathit{n}}_{{\mathit{NH}}_{\mathit{x}}}+0.1466\left({\mathit{n}}_{\mathit{Ar}}-1\right)\end{array}$

Figure 1
Structural formulas of different C-H-N-O, CNO and N_x (x = 6,8,10) monopropellants.

where: a, b, c and d are the number of carbon (C), hydrogen (H), nitrogen (N) and oxygen (O) atoms while is the number of -NH and -NH₂ groups, and (n_Ar) is the number of aromatic rings that might be present in the propellant compositions (Keshavarz 2008). Since both Eqs. 5 and 8 were derived with the help of the ISPBKW code, it will be useful to compare the predictive power of each of them with the code output. The results reported in Table 3 show that the specific impulses calculated using Eq. 5 are in good agreement (3 - 4% deviation) with the actual values obtained from the ISPBKW code. On the other hand, the application of Eq. 8 can, in certain instances, result in a large deviation (> 7%) in the calculated (I_sp) such as in the cases of structures showed in Figs. 1b, 1c, 1f, 1l, 1m, and 1q to 1t.

Table 3
Comparison between the specific impulse values calculated using Eqs. 5 and 8 to ISPBKW code results for different monopropellant compositions. Percentage deviations in parentheses.

Compositions	∆Hºf (kcal mol–1)	Ng	Q/(kcal g–1)	Isp/(Ns g–1)j	Isp (Eq. 5) (Ns g–1)	Isp(Eq. 8) (Ns g–1)
1a	9.88a	0.0245	1.368	2.22	2.22 (0)	2.21 (–0.55%)
1b	–161.53a	0.0310	1.609	2.48	2.62 (5.71%)	2.81(13.30%)
1c	–84.31a	0.0426	0.947	2.16	2.27 (5.13%)	2.49 (15.22%)
1d	144.5b	0.0238	1.692	2.65	2.53 (–4.63%)	2.65 (0)
1e	207.53c	0.0300	1.978	2.90	2.91 (0.48%)	2.77 (–4.49%)
1f	161.02c	0.0288	1.936	2.95	2.85 (–3.24%)	2.68 (–9.11%)
1g	106.74d	0.0381	1.432	2.65	2.63 (–0.70%)	2.79 (5.27%)
1h	36.33e	0.0372	1.344	2.61	2.53 (–3.36%)	2.59 (–0.75%)
1i	73.76e	0.0324	1.681	2.65	2.72 (2.52%)	2.58 (–2.63%)
1j	52.27e	0.0366	1.597	2.73	2.74 (0.30%)	2.63 (–3.51%)
1k	32.67e	0.0368	1.085	2.27	2.26 (–0.29%)	2.26 (–0.43%)
1l	61.28e	0.0378	1.171	2.37	2.38 (0.48%)	2.18 (–7.81%)
1m	112.69e	0.0394	1.286	2.49	2.53 (1.34%)	2.02 (–18.93%)
1n	56.96f	0.0347	1.198	2.30	2.32 (1.20%)	2.38 (3.67%)
1o	67.38f	0.0381	1.391	2.54	2.59 (1.97%)	2.43 (–4.28%)
1p	58.66g	0.0282	1.860	2.72	2.78 (2.24%)	2.56 (–5.78%)
1q	43.90h	0.0278	1.915	2.74	2.81 (2.64%)	2.47 (–9.78%)
1r	345.6i	0.0357	4.114	4.22	4.38 (3.87%)	2.56 (–39.28%)
1s	406.7i	0.0357	3.631	4.11	4.12 (0.11%)	2.61 (–36.53%)
1t	473.4i	0.0357	3.381	4.04	3.97 (–1.73%)	2.80 (-30.62%)
RMSD (Ns g–1)*					0.08	0.602

• ^a
  (Meyer et al. 2007);
• ^b
  (Dobratz and Crawford 1985);
• ^c
  (Christe et al. 2015);
• ^d
  (Fischer et al. 2012);
• ^e
  (Göbel et al. 2010);
• ^f
  (Klapötke et al. 2015);
• ^g
  (Ghule et al. 2011);
• ^h
  (Rahm et al. 2014);
• ⁱ
  (Lempert et al. 2009);
• ^j
  Equilibrium specific impulses were calculated using the ISPBKW thermochemical code (Mader 2008).
• ^*
  RMSD = Root-Mean-Square Deviation.

A graphical plot of the predicted (I_sp) using Eq. 5 and Eq. 8 versus ISPBKW code results is depicted in Fig. 2.

Figure 2
Specific impulse values of twenty monopropellants calculated using Eq. 5 and Eq. 8 versus values computed using ISPBKW code.

It can be shown that the data points obtained using the Keshavarz's method are more scattered around the diagonal line bisecting the graph (i.e. the line of perfect agreement between predicted and code results) compared to the ones obtained using the new method. Obviously, the major advantage of using Eq. 5 over Eq. 8 is the capability of the first to accurately predict the specific impulse of the yet hypothetical homoleptic polynitrogen compounds possessing the general formula N_x (x = 6, 8, 10, etc.).

SINGLE, DOUBLE, AND TRIPLE-BASE PROPELLANTS

Typical single-base (SB), double-base (DB), composite modified double-base (CMDB) and triple-base (TB) propellant formulations are listed in Table 5. Single-base propellants contain nitrocellulose, which has been gelatinized in acetone or in alcohol-ether solvent mixture and to which has been added various additives in order to improve the quality of the propellant powder. Likewise, double-base (DB) propellants are mixtures of nitrocellulose and nitroglycerine along with other additives, such as plasticizers, stabilizers and burn rate controllers, all of which alter the mechanical and thermal properties of the composition. The incorporation of solid oxidizers (e.g. ammonium perchlorate, ammonium dinitramide, etc.) and in some cases metallic fuel (e.g. aluminum) into the (DB) formulation, results in the formation of composite modified double-base (CMDB) propellants characterized by high specific impulse figures (Agrawal 2010).

Table 4
Atomic compositions and heat of formations of different ingredients used in triple-base and CMDB propellant compositions.

Compositions	Atomic compositions	∆H ºf (kcal mol–1)
NG	C3H5N3O9	–88.6a
NC (12% N)	C6H7.74N2.26O9.52	–173.7a
NC (13.35% N)	C6H7.29N2.71O10.41	–163.0a
NQ	CH4N4O2	–22.1a
RDX	C3H6N6O6	+14.71a
BDNPA-F (50/50 BDNPA/BDNPF)	C2.347H4.068N1.254O3.134	–46.39a
DEP	C12H14O4	–179.99b
2-NDPA	C12H10N2O2	18.40b
AP	NH4ClO4	–70.58a
ADN	H4N4O4	–35.99c
HNF	CH5N5O6	–17.21c
TAGAZ	C4H8N22	257.0d
Carbamite	C17H20N2O	–105.06e
DNC 90/7/3 NC(12% N)/NG/Carbamite	C2.329H3.017N0.886O3.535	–62.27
CL 78/20/2 NG/DEP/2-NDPA	C2.22H3.07N1.05O3.47	–46.48

• ^a
  (Dobratz and Crawford 1985);
• ^b
  (NIST 2017);
• ^c
  (Gadiot et al. 1993);
• ^d
  (Sivabalan et al. 2004);
• ^e
  (Meyer et al. 2007).

Table 5
Comparison between the specific impulse values calculated using the ISPBKW code and Eq. 5 for single-base, double-base, triple-base and CMDB propellant compositions. Percentage deviations in parentheses.

Single-base propellants	∆H ºf (kcal mol–1)a	Ng	Q/ (kcal g–1)	Isp/ (Ns g–1)f	Isp(Eq. 5) (Ns g–1)
M1	–53.80	0.0291	1.213	2.12	2.19 (3.07%)
M1A1	–57.40	0.0292	1.179	2.07	2.15 (3.80%)
M6	–53.80	0.0292	1.228	2.16	2.21 (2.00%)
M10	–59.30	0.0298	1.256	2.27	2.25 (–1.02%)
M12	–56.80	0.0296	1.245	2.23	2.23 (0)
M14	–54.10	0.0292	1.242	2.20	2.22 (1.06%)
IMR	–56.80	0.0296	1.247	2.24	2.24 (0)
Double-base propellants	∆H ºf (kcal mol–1)a	Ng	Q/ (kcal g–1)	Isp/ (Ns g–1)f	Isp(Eq. 5) (Ns g–1)
M2	–55.90	0.0304	1.319	2.37	2.33 (–1.75%)
M5	–56.80	0.0303	1.304	2.35	2.31 (–1.55%)
M7	–48.30	0.0302	1.387	2.45	2.39 (–2.27%)
M8	–47.50	0.0305	1.410	2.48	2.42 (–2.17%)
M9	–47.70	0.0305	1.422	2.50	2.44 (–2.47%)
M18	–55.70	0.0295	1.232	2.17	2.22 (2.11%)
M26	–50.40	0.0300	1.307	2.31	2.31 (0)
T25	–52.10	0.0299	1.295	2.30	2.29 (–0.47%)
Triple-base propellants	∆H ºf (kcal mol–1)a	Ng	Q/ (kcal g–1)	Isp/ (Ns g–1)f	Isp(Eq. 5) (Ns g–1)
M15	–30.20	0.0346	1.094	2.19	2.21 (0.97%)
M17	–31.90	0.0349	1.137	2.30	2.26 (–1.65%)
T34	–33.10	0.0347	1.088	2.20	2.21 (0.50%)
28/22.5/1.5/48 NC (12% N)/NG/Carbamite/Picriteb	–37.56	0.0343	1.131	2.28	2.24 (–1.63%)
28/22.5/1.5/48 NC (13.35% N)/NG/Carbamite/Picriteb	–35.20	0.0343	1.157	2.32	2.27 (–2.09%)
20.8/20.6/3.6/55 NC (13.35% N)/NG/Carbamite/Picriteb	–32.00	0.0347	1.107	2.25	2.23 (–0.81%)
28/22.5/1.5/38/10 NC (12% N)/NG/Carbamite/Picrite/RDXc	–34.77	0.0339	1.189	2.33	2.29 (–1.77%)
28/22.5/1.5/33/15 NC (12% N)/NG/Carbamite/Picrite/RDXc	–33.38	0.0336	1.219	2.36	2.32 (–1.75%)
28/22.5/1.5/28/20 NC (12% N)/NG/Carbamite/Picrite/RDXc	–31.98	0.0334	1.248	2.38	2.34 (–1.86%)
CMDB propellants	∆H ºf (kcal mol–1)a	Ng	Q/ (kcal g–1)	Isp/ (Ns g–1)f	Isp(Eq. 5) (Ns g–1)
29.5/32/8/1/29.5 DNC/NG/DEP/2-NDPA/APd	–54.96	0.0329	1.251	2.42	2.33 (–3.95%)
29.5/32/2/1/29.5/6 DNC/NG/DEP/2-NDPA/AP/BDNPA-Fd	–52.88	0.0334	1.302	2.49	2.39 (–4.01%)
29.5/32/8/1/29.5 DNC/NG/DEP/2-NDPA/RDXd	–35.30	0.0311	1.339	2.38	2.37 (–0.50%)
29.5/32/2/1/29.5/6 DNC/NG/DEP/2-NDPA/RDX/BDNPA-Fd	–33.23	0.0316	1.390	2.47	2.43 (–1.58%)
29.5/32/8/1/29.5 DNC/NG/DEP/2-NDPA/ADN	–45.82	0.0331	1.314	2.45	2.40 (–2.10%)
29.5/32/8/1/29.5 DNC/NG/DEP/2-NDPA/HNF	–40.03	0.0320	1.372	2.47	2.43 (–1.65%)
30/40/30 DNC/CL/TAGAZe	–16.68	0.0334	1.177	2.18	2.27 (3.96%)

• ^a
  Chemical compositions and heat of formations (HOFs): (Baer and Bryson 1961) otherwise stated; Other chemical compositions:
• ^b
  (Sanghavi et al. 2003);
• ^c
  (Sanghavi et al. 2006);
• ^d
  (Gore et al. 2002);
• ^e
  (Sivabalan et al. 2004);
• ^f
  Equilibrium specific impulses were calculated using the ISPBKW thermochemical code (Mader 2008).

On the other hand, standard triple-base (TB) propellants contain nitroguanidine (picrite), which has been added to the (NC-NG) matrix in order to reduce muzzle flash and gun barrel erosion (U.S. Army Material Command 1965). The condensed heats of formation and atomic compositions of (CMDB) and (TB) propellants (except M15, M17 and T34) were calculated from their individual ingredients shown in Table 4. The estimated specific impulses using Eq. 5 were in close agreement with thermochemical code results. Upon combustion, ammonium perchlorate containing compositions produces hydrogen chloride which is not taken into account in calculating the value of (N_g) and (Q), which explains the relatively high deviation of about ~4% in the predicted specific impulse for the CMBD formulations containing 29.5% ammonium perchlorate. It should be noted that many of the investigated (SB), (DB) and (TB) formulations contain small amount of mineral additives (e.g. KNO₃, K₂SO₄) used as flash reducers; however in this study, these salts were excluded in computing the (I_sp) values.

PSEUDO-PROPELLANTS

Pseudo-propellants are homogenous mixtures formed by physically mixing two or more ingredients possessing particle sizes on the order of 10 µm or less (Beckstead 2006). Numerical and experimental studies have been performed in order to study the combustion behavior and flame structure of pseudo-propellants especially nitramine/energetic binder binary systems (Kim et al. 2002; Lee et al. 1999). The use of energetic binders in propellant formulations has a distinctive advantage over traditional inert binders (e.g. HTPB) because they offer substantial additional energy during burning, which ultimately increases the overall specific impulse (Talawar et al. 2009). Some of the most studied nitramine-based pseudo-propellants are listed in Table 6 along with the calculated and estimated (I_sp) values, where one can clearly see that there is a very good agreement between the specific impulse values predicted using Eq. 5 and thermochemical code output.

Table 6
Comparison between the specific impulse values calculated using the ISPBKW code and Eq. 5 for nitramine-based pseudo-propellant compositions. Percentage deviations in parentheses.

Pseudo-propellant compositions	∆H ºf (kcal mol–1)a	Ng	Q/(kcal g–1)	Isp/(Ns g–1)b	Isp(Eq. 5) (Ns g–1)
80/20 RDX/GAP	10.96	0.0336	1.392	2.46	2.48 (1.03%)
71/9/20 RDX/GAP/BTTN	–0.96	0.0334	1.445	2.55	2.53 (–0.87%)
70/30 HMX/GAP	12.73	0.0335	1.342	2.35	2.43 (3.61%)
80/20 RDX/BAMO	17.26	0.0335	1.408	2.49	2.50 (0.16%)
70/30 HMX/BAMO	22.17	0.0334	1.367	2.41	2.46 (1.91%)
70/30 CL-20/GAP	23.89	0.0314	1.416	2.44	2.45 (0.48%)
80/20 CL-20/BAMO	29.56	0.0312	1.488	2.58	2.51 (–2.47%)

• ^a
  Heat of formation (HOF) and chemical composition of GAP and BAMO: (Gadiot et al. 1993); (HOF) of BTTN and CL-20: (NIST 2017) and (Meyer et al. 2007), respectively;
• ^b
  Equilibrium specific impulses were calculated using the ISPBKW thermochemical code (Mader 2008).

COMPOSITE PROPELLANTS

Ammonium perchlorate (AP)-based composite propellants (CPs) are by far the most important class of solid rocket propellants. Typical compositions are heterogeneous mixtures of an oxidizer mainly AP (60 - 80%) dispersed in a polymeric binder (e.g. HTPB, 10 - 15%) to which a metallic fuel such as aluminum (15 - 20%) may be added (Jain et al. 2009). Moreover, AP-based (CPs) offers high performance and excellent mechanical properties (Davenas 1993); however, they have some drawbacks, including the generation of large amounts of pollutants like toxic hydrogen chloride gas, which contributes to the depletion of the ozone layer (Lempert et al. 2006). Furthermore, the interaction of hydrogen chloride with the ambient atmosphere stimulates moisture condensation resulting in the formation of white secondary smoke, thereby making the firing position highly vulnerable to hostile action (Chaturvedi and Dave 2015). The need for powerful propellants with low environmental impact led to the development of chlorine-free oxidizers such as ammonium dinitramide (ADN) and hydrazinium nitroformate (HNF) which, in combination with suitable binders, can yield highly performant (CPs). The specific impulses for a number of (CP) formulations based on (ADN), (HNF) ammonium nitrate (AN) and high-enthalpy C-N-O organic oxidizers (see Fig. 3) have been calculated and are shown in Table 7.

Figure 3
Structural formulas of C-N-O organic oxidizers used in composite propellants.

Table 7
Comparison between the specific impulse values calculated using the ISPBKW code and Eq. 5 for ADN, AN, HNF, and organic oxidizer-based composite propellant compositions. Percentage deviations in parentheses.

ADN-based compositions	∆H ºf (kcal mol–1)	Ng	Q/(kcal g–1)	Isp/ (Ns g–1)f	Isp(Eq. 5) (Ns g–1)
80/20 ADN/GAPa	–17.55	0.0388	1.326	2.60	2.55 (–1.99%)
75/25 ADN/GAPa	–14.69	0.0384	1.307	2.57	2.52 (–1.89%)
70/30 ADN/GAPa	–11.82	0.0381	1.289	2.53	2.50 (–1.29%)
65/35 ADN/GAPa	–8.96	0.0377	1.270	2.48	2.47 (–0.37%)
60/40 ADN/GAPa	–6.09	0.0373	1.252	2.42	2.44 (0.77%)
50/50 ADN/GAPa	–0.36	0.0366	1.215	2.29	2.39 (4.21%)
74/26 ADN/ABb	–26.17	0.0384	1.397	2.47	2.60 (5.53%)
85/15 ADN/PMVTb	–20.16	0.0390	1.279	2.57	2.51 (–2.36%)
80/20 ADN/PVMDOb	–23.21	0.0391	1.367	2.62	2.59 (–0.97%)
AN-based compositions	∆H ºf (kcal mol–1)	Ng	Q/(kcal g–1)	Isp/ (Ns g–1)f	Isp(Eq. 5) (Ns g–1)
75/25 AN/ABb	–86.28	0.0410	1.054	2.29	2.34 (2.44%)
75/25 AN/PMVTb	–88.16	0.0420	0.889	2.24	2.20 (–2.10%)
85/15 AN/PVMDOb	–92.66	0.0423	0.986	2.34	2.31 (–1.47%)
60/20/20 AN/GAP/TMETNc	–112.41	0.0393	0.614	1.85	1.79 (–3.27%)
70/15/15 AN/GAP/TMETNc	–111.56	0.0404	0.696	2.01	1.93 (–4.16%)
60/15/15/10 AN/GAP/TMETN/NC(12%N)c	–107.24	0.0390	0.721	1.99	1.92 (–3.70%)
40/15/15/30 AN/GAP/TMETN/NC(12%N)c	–98.61	0.0362	0.772	1.94	1.89 (–2.43%)
40/15/15/30 AN/GAP/TMETN/HMXc	–77.04	0.0374	0.856	2.08	2.03 (–2.46%)
HNF-based compositions	∆H ºf (kcal mol–1)	Ng	Q/(kcal g–1)	Isp/ (Ns g–1)f	Isp(Eq. 5) (Ns g–1)
80/20 HNF/GAPd	–1.86	0.0361	1.481	2.66	2.63 (–1.40%)
80/20 HNF/PGNd	–18.95	0.0358	1.522	2.65	2.66 (0.22%)
80/20 HNF/PLNd	–19.55	0.0372	1.539	2.70	2.70 (0)
80/20 HNF/BAMOd	4.44	0.0360	1.498	2.68	2.64 (–1.63%)
80/20 HNF/HTPB	–10.29	0.0351	1.383	2.40	2.51 (4.57%)
Organic oxidizer-based compositions	∆H ºf (kcal mol–1)	Ng	Q/(kcal g–1)	Isp/ (Ns g–1)f	Isp(Eq. 5) (Ns g–1)
85/15 1f/ABe	85.02	0.0295	1.853	2.88	2.80 (–2.69%)
85/15 3u/ABe	60.58	0.0295	1.609	2.72	2.59 (–4.78%)
85/15 3v/ABe	76.92	0.0295	1.772	2.83	2.73 (–3.37%)
85/15 1e/AB	85.49	0.0304	1.889	2.86	2.85 (–0.49%)

• Chemical compositions:
• ^a
  (Wingborg et al. 2010);
• ^b
  (Manelis and Lempert 2009);
• ^c
  (Oyumi et al. 1996);
• ^d
  (Gadiot et al. 1993);
• ^e
  (Shastin and Lempert 2014);
• ^f
  Equilibrium specific impulses were calculated using the ISPBKW thermochemical code (Mader 2008). Heat of formation (HOF) values: AN (Dobratz and Crawford 1985); AB, PMVT and PVMDO (Manelis and Lempert 2009); TMETN (NIST 2017); HTPB (HOF) and atomic composition (Maggi and De Luca 2011); 3u and 3v (Shastin and Lempert 2014).

The good agreement (± 3 - 4% deviation) seen between ISPBKW code and Eq. 5 calculations indicates that the new model is capable of accurately predict the specific impulse of composite propellants having diverse chemical compositions and a wide range of performance capabilities.

LIQUID MONOPROPELLANTS AND BIPROPELLANTS

From an engineering point of view, a solid rocket motor (SRM) has far fewer components than a liquid rocket engine (LRE). While a (SRM) is basically a propellant charge (grain) fitted inside a metallic case to which is attached a supersonic exhaust nozzle, a (LRE) consists of a myriad of parts including thrust chambers, propellant tanks connected to a piping network, power sources, etc., all of which should work together in order to deliver the required thrust (Sutton and Biblarz 2001). Moreover, and in contrast to solid propellants, the fuel and the oxidizer that make up the liquid bipropellant are kept in separate tanks and are only mixed when injected into the engine's combustion chamber.

It is important to note, that an optimal mixing ratio (mass of oxidizer to mass of fuel, O/F) is carefully chosen not only to obtain high specific impulse, but also to keep the combustion temperature at an acceptable level.

The two major groups of bipropellant systems used today in (LRE) are cryogenic and storable propellants. The selection of one of these is influenced by many factors such as performance, cost, handling, toxicity, supply, and storage considerations. Other missile or space shuttle components like the auxiliary power drives and the roll-control thrusters (Huzel and Huang 1992) employ monopropellant systems that, unlike bipropellants, do not require an external oxidizer source in order to undergo an exothermic reaction. Only monopropellants formed by an oxidizer and a fuel dissolved in a homogenous liquid phase will be treated here; however other classes of liquid monopropellants also exist. For example nitromethane and isopropyl nitrate are those monopropellants where both the oxidizer and the fuel are held together through covalent bonds in the same molecule. The final class of liquid monopropellants includes those materials formed by an unstable arrangement of atoms such as hydrogen peroxide and hydrazine which, when brought into contact with a suitable catalyst, will decompose with the generation of thermal energy and gaseous products (U.S. Army Material Command 1969). Some representative liquid monopropellant and bipropellant compositions, along with their calculated performance characteristics, are shown in Tables 8 and 9. As it is evident from the two tables and the percentage deviation values, the specific impulse estimated using Eq. 5 compare favorably with the output of ISPBKW thermochemical code.

Table 8
Comparison between the specific impulse values calculated using the ISPBKW code and Eq. 5 for liquid monopropellant compositions. Percentage deviations in parentheses.

Liquid monopropellant compositions	∆H ºf (kcal mol–1)	Ng	Q/(kcal g–1)	Isp/ (Ns g–1)e	Isp(Eq. 5) (Ns g–1)
69.7/0.6/14.79/14.91 HAN/AN/MeOH/H2Oa	–141.34	0.0445	0.915	2.27	2.29 (1.14%)
77.25/0.67/17.19/4.89 HAN/AN/MeOH/H2Oa	–113.94	0.0433	1.085	2.43	2.43 (0%)
72.3/0.62/11.62/15.47 HAN/AN/EtOH/H2Ob	–135.98	0.0440	0.927	2.31	2.29 (–0.50%)
73.41/0.63/10.26/15.70 HAN/AN/1-PrOH/H2Ob	–133.49	0.0439	0.938	2.31	2.30 (–0.58%)
63.63/0.54/22.22/13.61 HAN/AN/Glycine/H2Ob	–142.33	0.0425	0.771	2.15	2.08 (–3.08%)
60/30/10 ADN/MAN/Ureac	–57.54	0.0411	1.105	2.45	2.40 (–2.17%)
40/40/20 ADN/MAN/Ureac	–73.95	0.0415	0.902	2.20	2.20 (0)
30/40/30 ADN/MAN/Ureac	–84.31	0.0416	0.744	1.97	2.03 (2.68%)
59.86/25/15.14 H2O2(70%)/AN/EtOHd	–172.85	0.0460	0.908	2.27	2.33 (2.56%)
80/8/12 H2O2(70%)/H2O/EtOHd	–213.13	0.0477	0.828	2.19	2.29 (4.51%)
36.67/51.20/12.13 H2O2(70%)/ADN/EtOHd	–108.13	0.0434	1.137	2.47	2.48 (0.45%)

• Chemical compositions:
• ^a
  (Chang et al. 2002);
• ^b
  (Wucherer et al. 2000);
• ^c
  (Ide et al. 2015);
• ^d
  (Martin et al. 2006);
• ^e
  Equilibrium specific impulses were calculated using the ISPBKW thermochemical code (Mader 2008).Heat of formation (HOF) values: HAN (Meng et al. 2009); MeOH, H2O, EtOH, 1-PrOH, Glycine and Urea (NIST 2017); H2O2 (70%) (Constantine and Cain 1967).

Table 9
Comparison between the specific impulse values calculated using the ISPBKW code and Eq. 5 for liquid bipropellant compositions. Percentage deviations in parentheses.

Liquid bipropellant compositions	∆H ºf (kcal mol–1)	Ng	Q/(kcal g–1)	Isp/(Ns g–1)e	Isp(Eq. 5) (Ns g–1)
N2O4/HEH (O/F = 1.94)a	–24.10	0.0372	1.511	2.68	2.68 (0)
N2O4-UDMH/HEH (80/20) (O/F = 2.45)a	–2.58	0.0374	1.660	2.79	2.81 (0.92%)
N2O4-UDMH/HEH (90/10) (O/F = 2.55)a	–0.42	0.0374	1.679	2.80	2.83 (1.06%)
N2O4/UDMH (O/F = 2.60)a	2.05	0.0374	1.696	2.81	2.84 (1.17%)
N2O4-UDMH/HEH (60/40) (O/F= 2.32)a	–5.94	0.0374	1.641	2.77	2.79 (0.87%)
RFNA/UDMH (O/F = 2.92)a	–43.83	0.0393	1.460	2.68	2.68 (0)
RFNA-UDMH/HEH (90/10) (O/F = 2.85)a	–45.77	0.0393	1.444	2.67	2.67 (0)
RFNA/HEH (O/F = 2.14)a	–64.32	0.0390	1.304	2.57	2.53 (–1.43%)
O2/RP-1 (O/F = 2.60)b	–18.41	0.0323	2.146	2.94	3.09 (5.27%)
O2/N2H4 (O/F = 0.91)b	15.16	0.0476	1.905	3.07	3.21(4.62%)
O2/Toluene (O/F = 1.87)c	–5.19	0.0279	2.026	2.84	2.91 (2.58%)
O2/Methylcyclohexane (O/F= 2.04)c	–21.69	0.0327	2.007	2.87	2.99 (4.29%)
O2/n-heptane (O/F = 2.05)c	–24.03	0.0341	2.017	2.88	3.03 (5.09%)
O2/Ethylene oxide (O/F = 1.10)d	–29.72	0.0326	1.985	2.87	2.97 (3.72%)
O2/Nitroethane (O/ F= 0.65)d	–31.58	0.0345	1.818	2.81	2.88 (2.61%)
O2/EtOH-75% (O/F = 1.30)d	–93.22	0.0379	1.640	2.71	2.80 (3.29%)
TNM/N2H4 (O/F = 1.40)d	18.38	0.0438	1.586	2.85	2.89 (1.27%)
H2O2 (90%)/N2H4 (O/F = 1.50)d	–79.15	0.0522	1.335	2.70	2.86 (5.90%)
RFNA-DETA/MA (80/20) (O/F = 3.00)d	–54.24	0.0388	1.364	2.61	2.58 (–0.94%)
RFNA/Hydine (O/F = 3.17)b	–48.55	0.0387	1.433	2.65	2.64 (–0.36%)
N2O4/N2H4 (O/F = 1.30)b	13.52	0.0456	1.584	2.87	2.92 (1.70%)
N2O4/Aerozine-50 (O/F = 2.00)b	6.32	0.0405	1.658	2.83	2.87 (1.41%)
N2O4/NO (70/30)-MeOH (O/F = 2.10)d	–45.03	0.0373	1.528	2.67	2.70 (0.90%)
N2O4/NO (70/30)-NH3 (O/F = 2.10)d	–20.17	0.0459	1.393	2.73	2.77 (1.38%)

• Chemical compositions:
• ^a
  (Keshavarz et al. 2011);
• ^b
  (U.S. Army Material Command 1969);
• ^c
  (Greenfield 1960);
• ^d
  (U.S. Army Ordnance Corps 1960);
• ^e
  Equilibrium specific impulses were calculated using the ISPBKW thermochemical code (Mader 2008). Heat of formation (HOF) values: N2O4, Toluene, Methylcyclohexane, n-heptane, Ethylene oxide, Nitroethane, N2H4, DETA, MA and TNM (NIST 2017); HEH and UDMH (Keshavarz et al. 2011); RFNA (Wright 1977); O2, NO, RP-1, NH3 (U.S. Army Material Command 1969).

HYBRID PROPELLANTS

The concept of a hybrid rocket, which employs a solid fuel and a liquid oxidizer (or vice-versa) as a propellant, is not new and dates back to the early 1930s (Krishnan 2002). In a typical hybrid rocket a highly pressurized gas is used to inject liquid oxidizer into the combustion chamber containing the solid grain fuel which causes the later to erode and vaporize leading to ignition and subsequent combustion. It is also well known that hybrid propellants burn as a macroscopic turbulent diffusion flame where the mixing ratio differs along the length of the grain, unlike solid and liquid propellants where the (O/F) value is uniform throughout the combustion chamber (Altman and Holzman 2007). Some features, like safety, the possibility to restart, and low cost are only few of the advantages that a hybrid rocket has over (SRM) and (LRE). A number of hybrid propellant formulations are shown in Table 10 along with their mixture ratios, from which the specific impulse was computed using the ISPBKW code and Eq. 5.

Table 10
Comparison between the specific impulse values calculated using the ISPBKW code and Eq. 5 for hybrid propellant compositions. Percentage deviations in parentheses.

Hybrid propellant compositions	∆H ºf (kcal mol–1)	Ng	Q/(kcal g–1)	Isp/(Ns g–1)e	Isp(Eq. 5) (Ns g–1)
O2/HTPB (O/F = 2.30)a	–10.91	0.0303	2.144	2.91	3.05 (4.82%)
H2O2 (90%)/PE (O/F = 7.80)a	–144.43	0.0442	1.385	2.63	2.73 (3.78%)
H2O2 (98%)/PE (O/F = 7.00)a	–125.53	0.0433	1.540	2.71	2.84 (4.56%)
H2O2 (98%)/DCPD (O/F = 6.20)a	–112.37	0.0413	1.600	2.70	2.84 (5.33%)
H2O2 (86%)/HTPB (O/F = 7.50)b	–117.89	0.0436	1.633	2.76	2.92 (5.60%)
H2O2 (92%)/HTPB (O/F = 6.50)b	–116.24	0.0428	1.609	2.75	2.88 (4.89%)
RFNA/HTPB (O/F = 4.90)c	–57.08	0.0344	1.457	2.54	2.56 (0.87%)
RFNA-HTPB/AP (90/10) (O/F = 3.80)c	–56.01	0.0343	1.427	2.56	2.54 (–1.09%)
N2O/Paraffin wax (O/F = 7.00)d	32.64	0.0344	1.359	2.60	2.47 (–4.77%)
N2O/HTPB (O/F = 7.40)a	37.38	0.0334	1.396	2.61	2.48 (–4.84%)
HAN(95%)/HTPB (O/F = 9.60)a	–89.89	0.0410	1.189	2.49	2.47 (–0.55%)

• Chemical compositions:
• ^a
  (Heister and Wernimont 2007);
• ^b
  (Rajesh et al. 2003);
• ^c
  (Venugopal et al. 2011);
• ^d
  (Bernard et al. 2011);
• ^e
  Equilibrium specific impulses were calculated using the ISPBKW thermochemical code (Mader 2008). Heat of formation (HOF) values: DCPD (Shark et al. 2013); H2O2 (92%) and H2O2 (86%) (Rajesh et al. 2003); H2O2 (90%) and H2O2 (98%) (Constantine and Cain 1967); N2O (Heister and Wernimont 2007); Paraffin wax (Bernard et al. 2011); PE (Risha et al. 2007).

Many hybrid compositions typically employ HTPB as fuel due to its ease of processing, low cost of production and availability (Sutton and Biblarz 2001). The results of specific impulse calculations show that, as in the case of solid and liquid propellants, Eq. 5 is also valid to estimate the specific impulse of hybrid formulations and an expected deviation of ± 3 - 5% from ISPBKW code is obtained for all tested samples.

CONCLUSION AND FUTURE SCOPE

The principal aim of the present study is to prove that, for a large body of C-H-N-O containing propellants, the specific impulse (I_sp) can be accurately obtained by applying Eq. 5 that employs only two variables, namely, the heat of reaction (Q) and the number of moles of gaseous reaction products per gram of propellant (N_g) calculated according to the well-known [H₂O-CO₂] arbitrary decomposition assumption, which is a method proposed and used by chemist Mortimer J. Kamlet and physicist Sigmund J. Jacobs to predict condensed high explosives performance in the late 1960s. Throughout the present study, Eq. 5 was used to estimate the (I_sp) of solid, liquid and hybrid propellants. The results were compared to the output of the ISPBKW code, which shows that a deviation of no more than ± 3 - 4% was obtained in most cases. Finally, future work should be directed toward finding a modified form of Eq. 5 capable of predicting the specific impulse of propellant formulations containing chlorine-based oxidizers and metals such as aluminum and boron.

APPENDIX: GLOSSARY OF COMPOUND NAMES AND ATOMIC COMPOSITIONS

AB: Active binder, poly(methylvinyltetrazole)/NG/2,4-dinitro-2,4-diazapentane (C₁₉H_34.5N₁₉O_29.5)

ADN: Ammonium dinitramide (H₄N₄O₄)

Aerozine-50: 50/50 hydrazine/UDMH (C_1.667H_12.909N_4.788)

AN: Ammonium nitrate (NH₄NO₃)

AP: Ammonium perchlorate (NH₄ClO₄)

BAMO: 3,3-bis(azidomethyl)oxetane (C₄H₆N₆O)_n

BDNPA-F: bis(2,2-dinitropropyl) acetal/bis(2,2-dinitropropyl) formal, 50/50 (C_2.347H_4.068N_1.254O_3.134)

BTNEU: 1,3-bis(2,2,2-trinitroethyl)urea (C₅H₆N₈O₁₃)

BTTN: 1,2,4-Butanetriol trinitrate (C₄H₇N₃O₉)

Comp-B: 63/36/1 RDX/TNT /Wax (C_2.03H_2.64N_2.18O_2.67)

CL-20: 2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (C₆H₆N₁₂O₁₂)

Cyclotol 60/40: RDX/TNT (C _2.04H_2.50N_2.15O_2.68)

DCPD: Dicyclopentadiene (C₁₀H₁₂)

DEGDN: Diethyleneglycol Dinitrate (C₄H₈N₂O₇)

DEP: Diethyl Phthalate (C₁₂H₁₄O₄)

DETA: Diethylenetriamine (C₄H₁₃N₃)

DDNP: Diazodinitrophenol (C₆H₂N₄O₅)

DINA: Dioxyethylnitramine Dinitrate (C₄H₈N₄O₈)

DIPAM: 3,3'-diamino-2,2',4,4',6,6'-hexanitrobiphenyl (C₁₂H₆N₈O₁₂)

DIPEHN: Dipentaerythritol Hexanitrate (C₁₀H₁₆N₆O₁₉)

DNDMOxm: Dinitrodimethyloxamide (C₄H₆N₄O₆)

DNOC: 4,6-Dinitro-o-cresol (C₇H₆N₂O₅)

DNPH: (2,4-Dinitrophenyl)hydrazine (C₆H₆N₄O₄)

EDDN: Ethylenediamine Dinitrate (C₂H₁₀N₄O₆)

EDNA: Ethylenedinitramine (C₂H₆N₄O₄)

ETN: Ethriol Trinitrate (C₆H₁₁N₃O₉)

FOX-7: 1,1-Diamino-2,2-dinitroethene (C₂H₄N₄O₄)

FOX-12: N-guanylurea-dinitramide (C₂H₇N₇O₅)

GAP: Glycidyl azide polymer (C₃H₅N₃O)_n

GUNI: Guanidine Nitrate (CH₆N₄O₃)

HAN: Hydroxylammonium nitrate (H₄N₂O₄)

HEH: Hydroxyethylhydrazine (C₂H₈N₂O)

HMX: 1,3,5,7-Tetranitro-1,3,5,7-tetraazacyclooctane (C₄H₈N₈O₈)

HNAB: 2,2',4,4',6,6'-Hexanitroazobenzene (C₁₂H₄N₈O₁₂)

HNF: Hydrazinium nitroformate (CH₅N₅O₆)

HNS: 2,2',4,4',6,6'-Hexanitrostilbene (C₁₄H₆N₆O₁₂)

HTPB: Hydroxyl-terminated polybutadiene (C_7.075H_10.65N_0.063O_0.223)

Hydine: 60/40 UDMH/DETA (C_3.551H_13.040N_3.163)

LX-14: 95/5 HMX/Estane (C_1.52H_2.92N_2.59O_2.66)

MA: Methylamine (CH₅N)

NG: Nitroglycerine (C₃H₅N₃O₉)

NQ: Nitroguanidine (CH₄N₄O₂)

NM: Nitromethane (CH₃NO₂)

Octol 75/25: 75/25 HMX/TNT (C_1.78H_2.58N_2.360_2.69)

PA: Picric Acid (C₆H₃N₃O₇)

Paraffin wax: (C₅₀H₁₀₂)

PBX-9007: 90/9.1/0.5/0.4 RDX/PS/DOP/Rosin (C_1.97H_3.22N_2.43O_2.44)

PBX-9011: 90/10 HMX/Estane (C_1.73H_3.18N_2.45O_2.61)

PBX-9404: 94/3/3 HMX/Nitrocellulose/ Tris-β-Chloroethyl phosphate (C_1.40H_2.75N_2.57O_2.69Cl_0.03P_0.01)

PBX-9501: 95/2.5/2.25 HMX/Estane/BDNPF (C_1.47H_2.86N_2.60O_2.69)

PE: Polyethylene (C₂H₄)_n

Pentolite (50/50): 50/50 TNT/PETN (C_2.33H_2.37N_1.29O_3.22)

PETN: Pentaerythritol tetranitrate (C₅H₈N₄O₁₂)

PGN: poly(glycidyl nitrate) (C₃H₅N₁O₄)_n

PLN: Polynitromethyloxetane (C₃H₉N₁O₄)_n

PMVT: Poly(methylvinyltetrazole) (C₄H₆N₄)_n

PVMDO: Poly(vinylmethoxydiazen-N-oxide) (C₃H₆N₂O₂)_n

RDX: 1,3,5-Trinitro-1,3,5-triazacyclohexane (C₃H₆N₆O₆)

RFNA: Red fuming nitric acid 84/14/2 HNO₃/NO₂/H₂O (H_0.931N_0.981O_2.826)

RP-1: Mixture of naphthenes/paraffins/C₁₂ olefins (CH_1.95)_n

TAGAZ: Triaminoguanidinium azotetrazolate (C₄H₈N₂₂)

TATB: 1,3,5-Triamino-2,4,6-trinitrobenzene (C₆H₆N₆O₆)

Tetryl: 2,4,6-Trinitrophenyl-N-methylnitramine (C₇H₅N₅O₈)

TMETN: Trimethylolethane trinitrate (C₅H₉N₃O₉)

TNM: Tetranitromethane (CN₄O₈)

TNT: 2,4,6-Trinitrotoluene (C₇H₅N₃O₆)

NC (12%N): Nitrocellulose (C₆H_7.74N_2.26O_9.52)

NC (13.35%N): Nitrocellulose (C₆H_7.29N_2.71O_10.41)

UDMH: Unsymmetrical dimethylhydrazine (C₂H₈N₂)

2-NDPA: 2-Nitrodiphenylamine (C₁₂H₁₀N₂O₂)

1a: 2,4,6,2',4',6'-Hexanitrodiphenylamine (C₁₂H₅N₇O₁₂)

1b: Mannitol Hexanitrate (C₆H₈N₆O₁₈)

1c: MAN, Methylamine Nitrate (CH₆N₂O₃)

1d: BTF, Benzotris[1,2,5]oxadiazole-1,4,7-trioxide (C₆N₆O₆)

1e: DTTO, di-1,2,3,4-tetrazine tetraoxide (C₂N₈O₄)

1f: FTDO, [1,2,5]Oxadiazolo[3,4-e][1,2,3,4]-Tetrazine-4,6- di-N-Oxide (C₂N₆O₃)

1g: TKX-50, dihydroxylammonium 5,5'-bistetrazole-1,1'-diolate (C₂H₈N₁₀O₄)

1h: ANTX, Ammonium 5-Nitrotetrazolate-2N-oxide (CH₄N₆O₃)

1i: 5-Nitrotetrazole-2N-oxide (CHN₅O₃)

1j: HxNTX, Hydroxylammonium 5-Nitrotetrazolate-2N-oxide (CH₄N₆O₄)

1k: GNTX, Guanidinium 5-Nitrotetrazolate-2N-oxide (C₂H₆N₈O₃)

1l: AGNTX, Aminoguanidinium 5-Nitrotetrazolate-2N-oxide (C₂H₇N₉O₃)

1m: TAGNTX, Triaminoguanidinium 5-Nitrotetrazolate-2N-oxide (C₂H₉N₁₁O₃)

1n: 5-Aminohydroximoyl-2-hydroxytetrazole (C₂H₄N₆O₂)

1o: Hydroxylammonium 5-aminohydroxyimoyl-tetrazole-2-oxide (C₂H₇N₇O₃)

1p: 1,2,3,4,5-pentanitrobicyclo[1.1.1]pentane (C₅H₃N₅O₁₀)

1q: Nitryl cyanide (CN₂O₂)

1r: Hexaazabenzene (N₆)

1s: Octaazacubane (N₈)

1t: Bipentazole (N₁₀)

3u: 5-Trinitromethyl-bistetrazolo[1,5-a:1',5'-c][1,3,5]triazine (C₄N₁₂O₆)

3v: Di(1H-triazirin-1-yl)-6-trinitromethyl-1,3,5-triazine (C₄N₁₂O₆)

M1: 83.13/9.78/4.89/0.98/0.73/0.49 NC (13.15%N)/Dinitrotoluene/Dibutylphthalate/Diphenylamine/Ethyl alcohol/Water (C_2.535H_3.102N_0.894O_3.370)

M1A1: 83.17/9.84/4.44/0.98/0.98/0.59 NC (12.60%N)/Dinitrotoluene/Dibutylphthalate/Diphenylamine/Ethyl alcohol/Water (C_2.577 H_3.237N_0.862O_3.357)

M6: 84.96/9.77/2.93/0.98/0.88/0.49 NC (13.15%N)/Dinitrotoluene/Dibutylphthalate/Diphenylamine/Ethyl alcohol/Water (C_2.467H_3.015N_0.911O_3.412)

M10: 96.93/0.99/0.10/1.48/0.49 NC (13.15%N)/Diphenylamine/Graphite/ Ethyl alcohol/Water (C_2.214H_2.854N_0.916O_3.606)

M12: 89.63/7.34/0.73/1.38/0.98 NC (13.15%N)/Dinitrotoluene/Diphenylamine/Ethyl alcohol/Water (C_2.309H_2.922N_0.927O_3.522)

M14: 88.02/7.82/1.96/0.98/0.98/0.25 NC (13.15%N)/Dinitrotoluene/Dibutylphthalate Diphenylamine/Ethyl alcohol/Water (C_2.406H_2.940N_0.918O_3.456)

IMR: 89.92/7.19/0.63/1.35/0.90 NC (13.15%N)/Dinitrotoluene/Diphenylamine/Ethyl alcohol/Water (C_2.301H_2.912N_0.927O_3.527)

M2: 76.80/19.34/0.59/0.30/2.28/0.69 NC (13.25%N)/NG/Ethyl centralite/Graphite/Ethyl alcohol/Water (C_2.049H_2.837N_0.986O_3.669)

M5: 81.26/14.87/0.59/0.30/2.28/0.69 NC (13.25%N)/NG/Ethyl centralite/Graphite/Ethyl alcohol/Water (C_2.085H_2.855N_0.970O_3.655)

M7: 58.71/38.17/0.97/0.86/1.29 NC (13.15%N)/NG/Ethyl centralite/ Ethyl alcohol/Carbon black (C_1.965H_2.565N_1.065O_3.683)

M8: 52.60/43.47/0.61/0.40/3.03 NC (13.25%N)/NG/Ethyl centralite/ Ethyl alcohol/Diethylphthalate (C_1.911H_2.609N_1.075O_3.710)

M9: 58.33/40.40/0.76/0.51 NC (13.25%N)/NG/Ethyl centralite/ Ethyl alcohol (C_1.844H_2.527N_1.091O_3.751)

M18: 79.60/9.95/8.96/1.00/0.50 NC (13.15%N)/NG/Dibutylphthalate/Diphenylamine/Ethyl alcohol (C_2.440H_3.145N_0.885O_3.446)

M26: 67.22/24.99/6.00/0.30/1.20/0.30 NC (13.15%N)/NG/Ethyl centralite/Graphite/Ethyl alcohol/ Water (C_2.224H_2.951N_1.006O_3.515)

T25: 73.21/19.99/5.00/0.30/1.20/0.30 NC (13.15%N)/NG/Ethyl centralite/Graphite/Ethyl alcohol/ Water (C_2.223H_2.890N_0.989O_3.532)

M15: 20.00/19.00/54.70/6.00/0.30 NC (13.15%N)/NG/NQ/Ethyl centralite/Ethyl alcohol (C_1.597H_3.532N_2.586O_2.565)

M17: 21.98/21.48/54.65/1.50/0.10/0.30/0.10 NC (13.15%N)/NG/NQ/Ethyl centralite/ Graphite/Ethyl alcohol/Water (C_1.395H_3.301N_2.602O_2.718)

T34: 20.00/19.00/54.70/4.00/2.00/0.30 NC (12.60%N)/NG/NQ/Dibutylphthalate/2-Nitrodiphenylamine/Ethyl alcohol (C_1.572H_3.524N_2.552O_2.614)

28/22.5/1.5/48 NC(12%N)/NG/Carbamite/Picrite: C_1.490H_3.273N_2.393O_2.830

28/22.5/1.5/48 NC(13.35%N)/NG/Carbamite/Picrite: C_1.445H_3.171N_2.420O_2.846

20.8/20.6/3.6/55 NC(13.35%N)/NG/Carbamite/Picrite: C_1.468H_3.369N_2.611O_2.649

28/22.5/1.5/38/10 NC(12%N)/NG/Carbamite/Picrite/RDX: C_1.529H_3.159N_2.278O_2.908

28/22.5/1.5/33/15 NC(12%N)/NG/Carbamite/Picrite/RDX: C_1.548H_3.102N_2.221O_2.947

28/22.5/1.5/28/20 NC(12%N)/NG/Carbamite/Picrite/RDX: C_1.568H_3.045N_2.164O_2.986

29.5/32/8/1/29.5 DNC/NG/DEP/2-NDPA/AP: C_1.598H_3.150N_0.944O_3.469Cl_0.251

29.5/32/2/1/29.5/6 DNC/NG/DEP/2-NDPA/AP/BDNPA-F: C_1.415H_3.016N_1.020O_3.549Cl_0.251

29.5/32/8/1/29.5 DNC/NG/DEP/2-NDPA/RDX: C_1.996H_2.942N_1.490O_3.261

29.5/32/2/1/29.5/6 DNC/NG/DEP/2-NDPA/RDX/BDNPA-F: C_1.813H_2.808N_1.565O_3.341

29.5/32/8/1/29.5 DNC/NG/DEP/2-NDPA/ADN: C_1.598H_3.096N_1.644O_3.416

29.5/32/8/1/29.5 DNC/NG/DEP/2-NDPA/HNF: C_1.759H_2.951N_1.499O_3.431

30/40/30 DNC/CL/TAGAZ: C_1.908H_3.576N_2.448O_2.448

80/20 RDX/GAP: C_1.687H_3.171N_2.767O_2.363

71/9/20 RDX/GAP/BTTN: C_1.564H_2.953N_2.440O_2.755

70/30 HMX/GAP: C_1.854H_3.406N_2.800O_2.194

80/20 RDX/BAMO: C_1.600H_2.940N_2.940O_2.291

70/30 HMX/BAMO: C_1.725H_3.059N_3.059O_2.085

70/30 CL-20/GAP: C_1.868H_2.474N_2.826O_2.220

80/20 CL-20/BAMO: C_1.615H_1.875N_2.970O_2.321

80/20 ADN/GAP: C_0.606H_3.589N_3.185O_2.781

75/25 ADN/GAP: C_0.758H_3.681N_3.176O_2.671

70/30 ADN/GAP: C_0.909H_3.772N_3.166O_2.560

65/35 ADN/GAP: C_1.061H_3.863N_3.156O_2.449

60/40 ADN/GAP: C_1.212H_3.955N_3.147O_2.339

50/50 ADN/GAP: C_1.515H_4.137N_3.127O_2.117

74/26 ADN/AB: C_0.494H_3.282N_2.880O_3.153

85/15 ADN/PMVT: C_0.545H_3.559N_3.286O_2.741

80/20 ADN/PVMDO: C_0.588H_3.756N_2.972O_2.972

75/25 AN/AB: C_0.475H_4.610N_2.349O_3.548

85/15 AN/PMVT: C_0.545H_5.066N_2.669O_3.186

85/15 AN/PVMDO: C_0.441H_5.130N_2.418O_3.480

60/20/20 AN/GAP/TMETN: C_0.998H_4.714N_2.340O_3.156

70/15/15 AN/GAP/TMETN: C_0.749H_4.785N_2.380O_3.304

60/15/15/10 AN/GAP/TMETN/NC(12%N): C_0.976H_4.578N_2.216O_3.290

40/15/15/30 AN/GAP/TMETN/NC(12%N): C_1.431H_4.165N_1.887O_3.262

40/15/15/30 AN/GAP/TMETN/HMX: C_1.154H_4.096N_2.441O_2.990

80/20 HNF/GAP: C_1.043H_3.195N_2.791O_2.824

80/20 HNF/PGN: C_0.941H_3.025N_2.353O_3.294

80/20 HNF/PLN: C_0.925H_3.648N_2.347O_3.272

80/20 HNF/BAMO: C_0.956H_2.964N_2.964O_2.752

80/20 HNF/HTPB: C_1.852H_4.315N_2.197O_2.666

85/15 1f/AB: C_1.374H_0.520N_3.557O_2.074

85/15 3u/AB: C_1.374H_0.520N_3.557O_2.074

85/15 3v/AB: C_1.374H_0.520N_3.557O_2.074

85/15 1e/AB: C_1.134H_0.520N_3.687O_2.140

69.70/0.6/14.79/14.91 HAN/AN/MeOH/H₂O: C_0.462H_6.435N_1.466O_4.215

77.25/0.67/17.19/4.89 HAN/AN/MeOH/H₂O: C_0.537H_5.940N_1.625O_4.051

72.30/0.62/11.62/15.47 HAN/AN/EtOH/H₂O: C_0.505H_6.274N_1.521O_4.146

73.41/0.63/10.26/15.70 HAN/AN/1-PrOH/H₂O: C_0.512H_6.198N_1.544O_4.124

63.63/0.54/22.22/13.61 HAN/AN/Glycine/H₂O: C_0.592H_5.669N_1.635O_4.018

60/30/10 ADN/MAN/Urea: C_0.485H_4.514N_2.905O_3.058

40/40/20 ADN/MAN/Urea: C_0.758H_5.172N_2.806O_2.898

30/40/30 ADN/MAN/Urea: C_0.925H_5.516N_2.817O_2.742

59.86/25/15.14 H₂O₂(70%)/AN/EtOH: C_0.657H_7.680N_0.625O_4.727

80/8/12 H₂O₂(70%)/H₂O/EtOH: C_0.521H_8.410O_5.330

36.67/51.20/12.13 H₂O₂(70%)/ADN/EtOH: C_0.527H_5.962N_1.651O_4.034

N₂O₄/HEH (O/F= 1.94): C_0.895H_3.579N_2.330O_3.317

N₂O₄-UDMH/HEH (80/20) (O/F= 2.45): C_0.927H_3.713N_2.471O_3.161

N₂O₄-UDMH/HEH (90/10) (O/F= 2.55): C_0.922H_3.695N_2.482O_3.156

N₂O₄/UDMH (O/F=2.60): C_0.927H_3.707N_2.496O_3.139

N₂O₄-UDMH/HEH (60/40) (O/F= 2.32): C_0.920H_3.679N_2.439O_3.196

RFNA/UDMH (O/F=2.92): C_0.850H_4.559N_2.070O_3.516

RFNA-UDMH/HEH (90/10) (O/F= 2.85): C_0.850H_4.557N_2.061O_3.523

RFNA/HEH (O/F= 2.14): C_0.837H_4.408N_1.954O_3.637

O₂/RP-1 (O/F= 2.60): C_1.989H_3.878O_4.513

O₂/N₂H₄ (O/F= 0.91): H_6.529N_3.265O_2.981

O₂/Toluene (O/F= 1.87): C_2.644H_3.021O_4.075

O₂/Methylcyclohexane (O/F= 2.04): C_2.345H_4.691O_4.194

O₂/n-heptane (O/F= 2.05): C_2.291H_5.238O_4.200

O₂/Ethylene oxide (O/F= 1.10): C_2.157H_4.313O_4.360

O₂/Nitroethane (O/F= 0.65): C_1.615H_4.037N_0.807O_4.077

O₂/EtOH-75% (O/F= 1.30): C_1.413H_5.445O_4.847

TNM/N₂H₄ (O/F= 1.40): C_0.298H_5.181N_3.784O_2.388

H₂O₂ (90%)/N₂H₄ (O/F= 1.50): H_8.836N_2.497O_3.509

RFNA-DETA/MA (80/20) (O/F= 3.00): C_0.936H_4.491N_1.971O_3.539

RFNA/Hydine (O/F= 3.17): C_0.852H_4.312N_2.004O_3.587

N₂O₄/N₂H₄ (O/F= 1.30): H_5.418N_3.940O_2.461

N₂O₄/Aerozine-50 (O/F= 2.00): C_0.555H_4.299N_3.044O_2.900

N₂O₄/NO (70/30)-MeOH (O/F= 2.10): C_1.005H_4.020N_1.710O_3.746

N₂O₄/NO (70/30)-NH₃ (O/F= 2.10): H_5.672N_3.601O_2.741

O₂/HTPB (O/F=2.30): C_2.144H_3.227N_0.019O_4.424

H₂O₂ (90%)/PE (O/F=7.80): C_0.814H_7.302O_5.181

H₂O₂ (98%)/PE (O/F=7.00): C_0.893H_7.023O_5.140

H₂O₂ (98%)/DCPD (O/F=6.20): C_1.051H_6.415O_5.058

H₂O₂ (86%)/HTPB (O/F= 7.50): C_0.842H_7.093N_0.007O_5.167

H₂O₂ (92%)/HTPB (O/F= 6.50): C_0.941H_6.877N_0.008O_5.105

RFNA/HTPB (O/F=4.90): C_1.196H_3.092N_1.371O_3.959

RFNA-HTPB/AP (90/10) (O/F=3.80): C_1.324H_3.296N_1.326O_3.850Cl_0.018

N₂O/Paraffin wax (O/F= 7.00): C_0.890H_1.816N_3.976O_1.988

N₂O/HTPB (O/F= 7.40): C_0.842H_1.267N_4.011O_2.028

HAN(95%)/HTPB (O/F= 9.60): C_0.665H_5.089N_1.798O_3.857

REFERENCES

• Agrawal JP (2010) High Energy Materials: Propellants, Explosives and Pyrotechnics. Weinheim: Wiley-VCH. doi: 10.1002/9783527628803
  » https://doi.org/10.1002/9783527628803
• Altman D, Holzman A (2007) Overview and history of hybrid rocket propulsion. In: Chiaverini MJ, Kuo KK, editors. Fundamentals of Hybrid Rocket Combustion and Propulsion. Virginia: AIAA. p. 1-36. doi: 10.2514/4.866876
  » https://doi.org/10.2514/4.866876
• Baer PG, Bryson KR (1961) Tables of Computed Thermodynamic Properties of Military Gun Propellants. (BRL-MR-1338) BRL Memorandum.
• Beckstead MW (2006) Recent progress in modeling solid propellant combustion. Combustion, Explosion and Shock Waves 42(3):623-641 doi: 10.1007/s10573-006-0096-5
  » https://doi.org/10.1007/s10573-006-0096-5
• Bernard G, Brooks MJ, Beaujardiere JP, Roberts LW (2011) Performance modeling of a paraffin wax / nitrous oxide hybrid rocket motor. Presented at: 49th AIAA Aerospace Sciences Meeting; Orlando, USA. doi: 10.2514/6.2011-420
  » https://doi.org/10.2514/6.2011-420
• Bhat VK, Kulkarni AR, Singh H (1988) Rapid estimation of specific impulse. Def Sci J 38(1):59-67 doi: 10.14429/dsj.38.4825
  » https://doi.org/10.14429/dsj.38.4825
• Bourasseau S (1990) A systematic procedure for estimating the standard heats of formation in the condensed state of non aromatic polynitro-compounds. J Energ Mater 8(5):416-441 doi: 10.1080/07370659008225432
  » https://doi.org/10.1080/07370659008225432
• Chang Y-P, Josten JK, Zhang BQ, Kuo KK, Reed BD (2002) Combustion characteristics of energetic HAN/methanol-based monopropellants. Presented at: 38th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit; Indianapolis, USA. doi: 10.2514/6.2002-4032
  » https://doi.org/10.2514/6.2002-4032
• Chaturvedi S, Dave PN (2015) Solid propellants: AP/HTPB composite propellants. Arabian Journal of Chemistry. doi: 10.1016/j.arabjc.2014.12.033
  » https://doi.org/10.1016/j.arabjc.2014.12.033
• Christe KO, Dixon DA, Vasiliu M, Wagner RI, Haiges R, Boatz JA, Ammon HL (2015) Are DTTO and iso-DTTO worthwhile targets for synthesis? Propellants, Explosives, Pyrotechnics 40(4):463-468. doi: 10.1002/prep.201400259
  » https://doi.org/10.1002/prep.201400259
• Constantine MT, Cain EFC (1967) Hydrogen Peroxide Handbook. (AFRPL-TR-67-144) ARFPL Technical Report.
• Davenas A (1993) Solid Rocket Propulsion Technology. Amsterdam: Pergamon. Chapter 10, Composite propellants; p. 415-475. doi: 10.1016/B978-0-08-040999-3.50015-1
  » https://doi.org/10.1016/B978-0-08-040999-3.50015-1
• Dobratz BM, Crawford PC (1985) LLNL Explosives Handbook: properties of chemical explosives and explosives simulants. (UCRL-52997-CHG-2) Lawrence Livermore National Laboratory Report.
• Fischer N, Fischer D, Klapötke TM, Piercey DG, Stierstorfer J (2012) Pushing the limits of energetic materials - the synthesis and characterization of dihydroxylammonium 5,5'-bistetrazole-1,1'-diolate. J Mater Chem 22(38):20418-20422. doi: 10.1039/C2JM33646D
  » https://doi.org/10.1039/C2JM33646D
• Frem D (2016) Simple correlations for the estimation of propellants specific impulse and the gurney velocity of high explosives. Combust Sci Technol 188(1):77-81. doi: 10.1080/00102202.2015.1081593
  » https://doi.org/10.1080/00102202.2015.1081593
• Frem D (2017) Predicting the plate dent test output in order to assess the performance of condensed high explosives. J Energ Mater 35(1):20-28 doi: 10.1080/07370652.2016.1143059
  » https://doi.org/10.1080/07370652.2016.1143059
• Gadiot GMHJL, Mul JM, Meulenbrugge JJ, Korting PAOG, Schnorkh AJ, Schöyer HFR (1993) New solid propellants based on energetic binders and HNF. Acta Astronautica 29(10-11):771-779 doi: 10.1016/0094-5765(93)90158-S
  » https://doi.org/10.1016/0094-5765(93)90158-S
• Ghule VD, Sarangapani R, Jadhav PM, Tewari SP (2011) Theoretical studies on polynitrobicyclo [1.1.1]pentanes in search of novel high energy density materials. Chem Pap 65(3):380-388. doi: 10.2478/s11696-011-0002-9
  » https://doi.org/10.2478/s11696-011-0002-9
• Göbel M, Karaghiosoff K, Klapötke TM, Piercey DG, Stierstorfer J (2010) Nitrotetrazolate-2N-oxides and the strategy of N-Oxide introduction. J Am Chem Soc 132(48):17216-17226. doi: 10.1021/ja106892a
  » https://doi.org/10.1021/ja106892a
• Gordon S, McBride BJ (1996) Computer program for calculation of complex chemical equilibrium compositions and applications I. Analysis and II. User's manual and program description. (NASA/RP-1311) NASA Technical Report.
• Gore GM, Tipare KR, Divekar CN, Bhatewara RG, Asthana SN (2002) Studies on effect of incorporation of BDNPF/A on burning rates of RDX/AP/AI filled CMDB propellants. J Energ Mater 20(3):255-278 doi: 10.1080/07370650208244824
  » https://doi.org/10.1080/07370650208244824
• Greenfield S (1960) An experimental evaluation of rocket propellant data. In: Penner SS, Ducarme J, editors. The Chemistry of Propellants. Paris: Pergamon. p. 169-227 doi: 10.1016/B978-1-4831-9626-8.50011-8
  » https://doi.org/10.1016/B978-1-4831-9626-8.50011-8
• Hardesty DR, Kennedy JE (1977) Thermochemical estimation of explosive energy output. Combust Flame 28:45-59. doi: 10.1016/0010-2180(77)90007-4
  » https://doi.org/10.1016/0010-2180(77)90007-4
• Heister S, Wernimont E (2007) Hydrogen peroxide, hydroxyl ammonium nitrate, and other storable oxidizers. In: Chiaverini MJ, Kuo KK, editors. Fundamentals of Hybrid Rocket Combustion and Propulsion. Virginia: AIAA. p. 457-488. doi: 10.2514/5.9781600866876.0457.0488
  » https://doi.org/10.2514/5.9781600866876.0457.0488
• Huzel DK, Huang DH (1992) Modern engineering for design of liquid-propellant rocket engines. Washington: AIAA. doi: 10.2514/4.866197
  » https://doi.org/10.2514/4.866197
• Ide Y, Takahashi T, Iwai K, Nozoe K, Habu H, Tokudome S (2015) Potential of ADN-based ionic liquid propellant for spacecraft propulsion. Procedia Engineering 99:332-337. doi: 10.1016/j.proeng.2014.12.543
  » https://doi.org/10.1016/j.proeng.2014.12.543
• Jain S, Mehilal M, Nandagopal S, Singh PP, Radhakrishnan KK, Bhattacharya B (2009) Size and shape of ammonium perchlorate and their influence on properties of composite propellant. Def Sci J 59(3):294-299. doi: 10.14429/dsj.59.1523
  » https://doi.org/10.14429/dsj.59.1523
• Kamlet MJ, Jacobs SJ (1968) Chemistry of detonations. I. A simple method for calculating detonation properties of C-H-N-O explosives. The Journal of Chemical Physics 48(1):23-35. doi: 10.1063/1.1667908
  » https://doi.org/10.1063/1.1667908
• Kamlet MJ, Finger M (1979) An alternative method for calculating gurney velocities. Combust Flame 34:213-214. doi: 10.1016/0010-2180(79)90095-6
  » https://doi.org/10.1016/0010-2180(79)90095-6
• Keshavarz MH (2008) Prediction method for specific impulse used as performance quantity for explosives. Propellants, Explosives, Pyrotechnics 33(5):360-364. doi: 10.1002/prep.200800224
  » https://doi.org/10.1002/prep.200800224
• Keshavarz MH (2012) Predicting maximum attainable detonation velocity of CHNOF and aluminized explosives. Propellants, Explosives, Pyrotechnics 37(4):489-497. doi: 10.1002/prep.201100097
  » https://doi.org/10.1002/prep.201100097
• Keshavarz MH, Nazari HR (2006) A simple method to assess detonation temperature without using any experimental data and computer code. J Hazard Mater 133(1-3):129-134. doi: 10.1016/j.jhazmat.2005.10.001
  » https://doi.org/10.1016/j.jhazmat.2005.10.001
• Keshavarz MH, Ramadan A, Mousaviazar A, Zali A, Shokrollahi A (2011) Reducing dangerous effects of unsymmetrical dimethyl hydrazine as a liquid propellant by addition of hydroxyethylhydrazine, Part II, Performance with several oxidizers. J Energ Mater 29(3):228-240. doi: 10.1080/07370652.2010.514320
  » https://doi.org/10.1080/07370652.2010.514320
• Keshavarz MH, Zamani A, Shafiee M (2014) Predicting detonation performance of CHNOFCl and aluminized explosives. Propellants, Explosives, Pyrotechnics 39(5):749-754. doi: 10.1002/prep.201300169
  » https://doi.org/10.1002/prep.201300169
• Kim ES, Yang V, Liau YC (2002) Modeling of HMX/GAP pseudo-propellant combustion. Combust Flame 131(3):227-245. doi: 10.1016/S0010-2180(02)00411-X
  » https://doi.org/10.1016/S0010-2180(02)00411-X
• Kinney GR (1960) High energy liquid propellants for rocket. Presented at: 1958 Cryogenic Engineering Conference. Proceedings of the 1958 Cryogenic Engineering Conference; Massachusetts, USA. doi: 10.1007/978-1-4757-0540-9_1
  » https://doi.org/10.1007/978-1-4757-0540-9_1
• Klapötke TM (2011) Chemistry of high-energy materials. Berlin: Walter de Gruyter GmbH & Co.
• Klapötke TM, Kurz MQ, Schmid PC, Stierstorfer J (2015) Energetic improvements by N-oxidation: insensitive amino-hydroximoyl-tetrazole-2N-oxides. J Energ Mater 33(3):191-201. doi: 10.1080/07370652.2014.963743
  » https://doi.org/10.1080/07370652.2014.963743
• Krishnan S (2002) Hybrid rocket technology: an overview. Presented at: 6th Asia Pacific International Symposium on Combustion and Energy Utilization; Kualalumpur, Malaysia.
• Kubota N (2015) Propellants and explosives: thermochemical aspects of combustion. 3rd ed. Weinheim: Wiley-VCH.
• Lee Y, Tang C-J, Litzinger TA (1999) Thermal decomposition of RDX/BAMO pseudo-propellants. Combust Flame 117(4):795-809. doi: 10.1016/S0010-2180(98)00131-X
  » https://doi.org/10.1016/S0010-2180(98)00131-X
• Lempert DB, Nechiporenko GN, Dolganova GP, Soglasnova SI (2006) Solid composite propellants of low pollution. Presented at: International Workshop "Nonequilibrium Processes in Combustion and Plasma Based Technologies"; Minsk, Belarus.
• Lempert DB, Nechiporenko GN, Soglasnova SI (2009) Energetic potential of compositions based on high-enthalpy polynitrogen compounds. Combust Explos Shock Waves 45(2):160-168. doi: 10.1007/s10573-009-0021-9
  » https://doi.org/10.1007/s10573-009-0021-9
• Lempert D, Nechiporenko G, Manelis G (2011) Energetic performances of solid composite propellants. Cent Eur J Energ Mater 8(1):25-38.
• Mader CL (2008) Numerical modeling of explosives and propellants. 3rd ed. Boca Raton: CRC Press. doi: 10.1201/9781420052398
  » https://doi.org/10.1201/9781420052398
• Maggi F, De Luca LT (2011) Assessment of rocket exhaust pollution through thermochemistry. Presented at: 4th European Conference for Aerospace Sciences (EUCASS); Saint Petersburg, Russia.
• Manelis GB, Lempert DB (2009) Ammonium nitrate as an oxidizer in solid composite propellants. Progress in Propulsion Physics 1:81-96. doi: 10.1051/eucass/200901081
  » https://doi.org/10.1051/eucass/200901081
• Martin JD, Lundstrom NH, Scheffe RS (2006) Premixed liquid monopropellant solutions and mixtures. United States Patent US 6,984,273 B1.
• Meng M, Khare P, Risha G, Yetter R, Yang V (2009) Decomposition and ignition of HAN-based monopropellants by electrolysis. Presented at: 47th AIAA Aerospace Sciences Meeting; Orlando, USA. doi: 10.2514/6.2009-451
  » https://doi.org/10.2514/6.2009-451
• Meyer R, Köhler J, Homburg A (2007) Explosives. 6th ed. Weinheim: Wiley-VCH.
• NIST (2017) Standard Reference Data Base Number 69; [accessed 2017 April 21]. http://webbook.nist.gov/chemistry
  » http://webbook.nist.gov/chemistry
• Oyumi Y, Kimura E, Hayakawa S, Nakashita G, Kato K (1996) Insensitive munitions (IM) and combustion characteristics of GAP/AN composite propellants. Propellants, Explosives, Pyrotechnics 21(5):271-275. doi: 10.1002/prep.19960210511
  » https://doi.org/10.1002/prep.19960210511
• Rahm M, Bélanger-Chabot G, Haiges R, Christe KO (2014) Nitryl cyanide, NCNO2. Angew Chem Int Ed 53(27):6893-6897. doi: 10.1002/anie.201404209
  » https://doi.org/10.1002/anie.201404209
• Rajesh K, Kuznetsov KA, Natan B (2003) Design of a lab-scale HP/HTPB hybrid rocket motor. Presented at: 39^th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit; Huntsville, USA. doi: 10.2514/6.2003-4744
  » https://doi.org/10.2514/6.2003-4744
• Risha GA, Evans BJ, Boyer E, Kuo KK (2007) Metals, energetic additives, and special binders used in solid fuels for hybrid rockets. In: Chiaverini MJ, Kuo KK, editors. Fundamentals of Hybrid Rocket Combustion and Propulsion. Virginia: AIAA. p. 413-456. doi: 10.2514/5.9781600866876.0413.0456
  » https://doi.org/10.2514/5.9781600866876.0413.0456
• Sanghavi RR, Pillai AGS, Velapure SP, Singh A (2003) Studies on different types of nitrocellulose in triple base gun propellant formulations. J Energ Mater 21(2):87-95. doi: 10.1080/713845496
  » https://doi.org/10.1080/713845496
• Sanghavi RR, Khire VH, Chakraborthy TK, Singh A (2006) Studies on RDX influence on performance increase of triple base propellants. Propellants, Explosives, Pyrotechnics 31(4):318-321. doi: 10.1002/prep.200600044
  » https://doi.org/10.1002/prep.200600044
• Shark SC, Pourpoint TL, Son SF, Heister SD (2013) Performance of dicyclopentadiene/H₂O₂-based hybrid rocket motors with metal hydride additives. J Propul Power 29(5):1122-1129 doi: 10.2514/1.B34867
  » https://doi.org/10.2514/1.B34867
• Shastin AV, Lempert DB (2014) Energy potential of some triazine derivatives. Russian Journal of Physical Chemistry B 8(5):716-719. doi: 10.1134/s1990793114050212
  » https://doi.org/10.1134/s1990793114050212
• Sivabalan R, Talawar MB, Senthilkumar N, Kavitha B, Asthana SN (2004) Studies on azotetrazolate based high nitrogen content high energy materials potential additives for rocket propellants. J Therm Anal Calorim 78(3):781-792. doi: 10.1007/s10973-005-0446-0
  » https://doi.org/10.1007/s10973-005-0446-0
• Sutton GP, Biblarz O (2001) Rocket propulsion elements. 7th ed. New York: John Wiley & Sons.
• Talawar MB, Sivabalan R, Mukundan T, Muthurajan H, Sikder AK, Gandhe BR, Rao AS (2009) Environmentally compatible next generation green energetic materials (GEMs). J Hazard Mater 161(2-3):589-607. doi: 10.1016/j.jhazmat.2008.04.011
  » https://doi.org/10.1016/j.jhazmat.2008.04.011
• Thompson Jr. RJ (1960) High temperature thermodynamics and theoretical performance evaluation of rocket propellants. In: Penner SS, Ducarme J, editors. The Chemistry of Propellants. Paris: Pergamon. p. 25-120. doi: 10.1016/B978-1-4831-9626-8.50009-X
  » https://doi.org/10.1016/B978-1-4831-9626-8.50009-X
• Trusov BG (2002) Program system TERRA for simulation phase and thermal chemical equilibrium. Presented at: XIV International Symposium on Chemical Thermodynamics. Proceedings of XIV International Symposium on Chemical Thermodynamics; St-Petersburg, Russia.
• U.S. Army Ordnance Corps (1960) Ordnance engineering design handbook, ballistic missile series: propulsion and propellants. (AMCP 706-282) Washington: US Army Materiel Command.
• U.S. Army Material Command (1965) Engineering design handbook ballistic series: interior ballistics of guns. (AMCP 706-150) Washington: US Army Materiel Command.
• U.S. Army Material Command (1969) Engineering design handbook elements of aircraft and missile propulsion. (AMCP 706-285) Washington: US Army Materiel Command.
• Venugopal S, Ramanujachari V, Rajesh KK (2011) Combustion experiments of HTPB/RFNA mixed hybrid propellants. Indian Journal of Science and Technology 4(10):1267-1272. doi: 10.17485/ijst/2011/v4i10/30170
  » https://doi.org/10.17485/ijst/2011/v4i10/30170
• Wingborg N, Andreasson S, de Flon J, Johnsson M, Liljedahl M, Oscarsson C, Pettersson Å, Wanhatalo M (2010) Development of ADN-based minimum smoke propellants. Presented at: 46th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit; Nashville, USA. doi: 10.2514/6.2010-6586
  » https://doi.org/10.2514/6.2010-6586
• Wright AC (1977) USAF propellant handbooks. Nitric acid/nitrogen tetroxide oxidizers. Volume II. (AFRPL-TR-76-76) AFRPL Technical Report.
• Wucherer EJ, Christofferson S, Reed B (2000) Assessment of high performance HAN- monopropellants. Presented at: 36th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit; Huntsville, USA. doi: 10.2514/6.2000-3872
  » https://doi.org/10.2514/6.2000-3872

Edited by

Section Editor: Adam Cumming

Data availability

Data citations

NIST (2017) Standard Reference Data Base Number 69; [accessed 2017 April 21]. http://webbook.nist.gov/chemistry

Publication Dates

• Publication in this collection
  16 July 2018
• Date of issue
  2018

History

• Received
  25 May 2017
• Accepted
  29 Oct 2017