船舶在极端波浪条件下会产生剧烈的砰击，瞬时产生的巨大作用力会造成船体结构的损坏，因此准确预估入水砰击过程非常重要。本文通过数值和实验，分析楔形体入水过程中运动、受力以及自由表面的变化情况，验证光滑粒子流体动力学（SPH）方法在楔形体入水问题上的适用性和准确性，并使用此方法分析楔形体入水时楔形体斜升角和入水速度的影响。结果表明，光滑粒子流体动力学方法在解决入水问题上有很好的准确性，在楔形体受力和自由表面变形上与实验结果有很好的吻合度。通过计算发现，最大砰击力与楔形体斜升角的三次方成正比，与入水速度的二次方成正比，增大楔形体的斜升角和降低入水速度，都可有效减少入水砰击力。
The ship is subject to severe slamming under extreme wave conditions. The large instantaneous force would cause great damage to the hull structure. It is thus of great significance to estimate such water entry process accurately. The current work conducted numerical and experimental study to investigate the movement and force of the wedge body, and the deformation of free surface during the water entry process. The smoothed particle hydrodynamics (SPH) method was used to solve the current water entry problem after verifying the applicability and accuracy of this method. Then the effects of the deadrise angle and the speed of the wedge were studied. The results show that the SPH method has good accuracy in studying the water entry problem and there is a good agreement of the numerical and experimental results in the force on the wedge and the free surface deformation. It is found that maximum slamming force is to the cube of the wedge's deadrise angle and proportional to the square of the water entry velocity. The increase in the wedge's deadrise angle and decrease in the speed of water entry can effectively reduce the slamming force caused by the water entry process.
2021,43(1): 53-60 收稿日期：2019-12-23
DOI：10.3404/j.issn.1672-7649.2021.01.010
分类号：TJ630
作者简介：陈光茂(1993-),男,硕士研究生,研究方向为流体力学
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