Abstract:

The computational fluid dynamics (CFD) technique is used to investigate the thermal-dynamic coupled process in cryogenic liquid oxygen tank under the slosh excitations. The influences of the external environmental heat leak and the phase change occurring on the liquid-vapor interface are considered in detail. The slosh force, fluid slosh momentum, tank pressure, and fluid temperature distribution in tank caused by the external excitation are analyzed. The results show that both the slosh force suffered by tank and fluid slosh momentum have reducing trends with fluctuations under the external sinusoidal excitation. Influenced by the external slosh, the connection area between the subcooled liquid and the superheated vapor increases, so the superheated vapor is greatly cooled by the liquid, and the tank pressure decreases almost linearly with time. As for the fluid temperature monitors, while they are close to the liquid-vapor interface, the fluid sloshing has an obvious effect on the variation of monitors' temperature. In general, the temperature distribution in the tank is formed with the high temperature region in upper and low temperature region in bottom, and the high temperature in the external region and the low temperature in the interior. While as located on the top of tank, the vapor test points have a large temperature fluctuation, influenced by the top dished-head. For the bottom liquid temperature monitors, their values are larger than parts of liquid test points' temperature, with the direct heat transfer from the bottom dished-head wall.

摘要：

采用计算流体力学（CFD）技术数值研究了外部晃动激励下低温液氧贮箱内部热力耦合过程。计算中详细考虑了贮箱外部漏热以及气液相间传热的影响，分析了正弦激励对箱体所受晃动力、流体反作用晃动力矩、箱体压力以及箱内流体温度分布的影响。计算结果表明：外部正弦激励使箱体所受晃动力以及流体晃动力矩呈波动降低的变化；晃动使过冷液体对过热气相以及高温壁面产生良好的冷却作用，以致在整个过程中箱体压力近似线性降低。对于气液相温度测点，其距离界面越近，受流体晃动影响越显著。整体上，贮箱内部流体温度呈现上部高下部低、外部高内部低的分布。由于处在贮箱顶部的气相温度测点受箱体上封头影响较大，气相温度出现大幅波动；而处在贮箱底部的液相温度测点直接接受壁面对流换热，其温度值略高于其他液相测点。