【作者】 郝威巍；

【导师】 宗智；

【作者基本信息】 大连理工大学 ， 船舶与海洋结构物设计制造， 2009， 硕士

【摘要】 随着我国社会主义现代化进程的加速发展,我国的国防事业也得到进一步加强,海军的力量更是关乎国家主权实力的体现。作为海上力量,抗爆性是舰船生命力的一项重要指标,二战以来各国竞相在水中兵器方面展开研究,水下爆炸的理论也得到发展。水下爆炸是较为复杂的能量转换过程。现有理论认为根据能量及其破坏力可将水下爆炸划分为两个阶段:冲击波部分和气泡脉动部分。早期的学者研究范围仅局限在冲击波部分,认为高频冲击波是造成舰船毁伤的原因,研究方法多以实船实验和数学推导为主。后来人们发现,冲击波的作用仅是造成局部板架、舱段的破坏,因为冲击波的能量虽高,其频率的量级与板架相同,破坏是局部性的。随着实船实验和计算机数值模拟技术的发展,人们发现低频的脉动气泡与舰船固有频率相近,是造成舰船总体破坏折断的真正原因,脉动气泡成为学术研究热点。本文用数值模拟的方式对水下爆炸的气泡脉动的溃灭过程进行了研究,利用LS-DYNA对大量工况进行了数值计算,将结果进行了横向和纵向比较。包括有、无壳情况下相同、不同药包半径的气泡运动规律,网格对压力的影响,壳厚对压力的影响,气泡压力与形状的关系,运动过程中的旋度问题,重力的影响,不同观察点计算结果的差异等。更多还原

【Abstract】 With the acceleration of socialist modernization of China’s development, China’s defense industry has also been further strengthened. The power of the navy is an authoritativeness symble of national sovereignty. As naval forces, antiknock ability is an important indicator of the vitality of ships. Underwater weapons have been studied competly by most contries since World War II, therefore the theory for underwater explosion theory has been developed.Underwater explosion is a more complex and conversion process with the energy. Existing theory suggests that according to the energy and the destructive power, an underwater explosion can be divided into two stages: shock wave and the pulse of the bubble. Scope of the study of early scholars in the shock wave is only limited to some that the high-frequency shock wave which they thought causes the ships’ damage, research methods make more use of real ship experiments and mathematical analysis. Later it was found that the role of shock wave only caused partial damage, such like plate frame, compartment. That because even though the shock wave energy is high, but its frequency is at the same magnitude with the plates, that’s why the destruction is partial. With the real ship experimental and numerical simulation developed, it was discovered that low-frequency pulse of the bubble is similar to the natural frequency of the ship which cause the overall damage of ship, therefore pulsating bubbles become the research hotspot.In this paper, underwater explosion bubble pulsation-Bubble Collapse process is studied with numerical simulation methods, using LS-DYNA on a large number of working conditions has been calculated; the results were horizontal and vertical comparison. Including, law of motion with and without shell cases, different radius of bubbles, same as the impact on the pressure results of the grid, the impact of shell thickness on the pressure results, the relationship between bubble pressure and the shape, rotation problems in the process of movement, the effect of gravity, the different calculation results with different observation points.更多还原