Investigation of Wedge Water-Entry Under Symmetric Impact Loads by Experimental Tests

M. Nikfarjam O. B. Yaakob M. S. Seif J. Koto About the authors

Abstract

One of the main challenges for engineers in designing high-speed crafts is the evaluation of hydrodynamic loads during the impact of hull to wave’s surface. This paper presents an experimental investigation on the pressure distribution on three wedge-sections with 15°, 20° and 30° deadrise during water-entry. Assessment of pressure distribution on the effects of parameters such as drop heights, deadrise angles and the weights of the models had done. Time histories of impact pressure were recorded. It was showed that, the maximum pressure for 20° wedge had increased 2.4 times in comparison with 30° wedge while this number is 1.23 time for the 15° wedge. But the effects of weight and drop height were not as much as deadrise angle.

The results give an appropriate approximation of the maximum pressures by the model resembling high-speed craft’s hull sections, which can be used to estimate impact loads in different operational condition. The condition of water level during the impact process has also been observed in each test. The nature of impact test with non-constant speed can clarify the real behavior of falling objects, which can be assumed as the significance of current study.

Keywords:
Water impact; Wedge; Pressure; High speed craft; Slamming

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