Propellant sloshing is one of the potential sources of disturbance which affects the stability and structural integrity of space vehicles. In this study, using a small scale model of the first Korean lunar orbiter fuel tank, which is partially filled with liquid fuel, the dynamic lateral sloshing has been simulated by CFD analysis for various fill-levels. Spherical tank geometry was assumed, because it is one of the options for the fuel tank. After applying an accelerated motion to the fuel tank, the dynamic sloshing forces exerted on the tank wall in lateral directions during a free sloshing motion were measured and analyzed to identify the sloshing frequencies. The results show very good consistency with the mathematical and experimental studies from available sources in NASA technical reports. A simple inexpensive experimental work was also performed successfully to verify the fundamental slosh frequency. The methodology developed here would be useful for understanding the slosh dynamics and for modeling of the propellant sloshing in a fuel tank of an arbitrary geometry.

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球罐侧向晃荡的 CFD 分析与实验

推进剂晃荡是影响航天器稳定性和结构完整性的潜在干扰源之一。在这项研究中，使用部分填充液体燃料的韩国第一个月球轨道飞行器燃料箱的小比例模型，通过 CFD 分析模拟了各种填充水平的动态横向晃动。假设球形油箱几何形状，因为它是油箱的选项之一。在对燃料箱施加加速运动后，测量和分析在自由晃荡运动期间施加在油箱壁上的横向动态晃荡力，以确定晃荡频率。结果显示与 NASA 技术报告中可用来源的数学和实验研究非常一致。还成功地进行了简单廉价的实验工作以验证基本晃动频率。这里开发的方法对于理解晃动动力学和模拟任意几何形状的燃料箱中的推进剂晃动非常有用。