氮气强制对流消除煤油温度分层及其液氮降温系统分析

为找到煤油贮罐降温后的温度分层原因，通过分析煤油贮罐不同深度的温度，结合管道布置走向，发现煤油降温流动过程中存在上部滞流区，导致煤油贮罐形成上部热煤油和下部冷煤油分层。采用鼓泡与泵回流两种方式进行对比试验，结果表明鼓泡能较好消除煤油贮罐在垂直方向上的温度不均，泵回流方式无明显效果。为准确预估降温后的煤油温度，采用不同调温方式进行多次试验，构建了煤油调温目标温度计算模型，作为煤油降温停止的判断准则。鼓泡方法和调温模型已成功应用于天舟一号发射任务，有效保障了煤油推进剂的温度品质。

Eliminating Kerosene Thermal Stratification by Nitrogen Forced Convection and Analysis of Its Liquid Nitrogen Cooling System

In order to find the reason of the thermal stratification in kerosene storage tank after cooling, the temperature data is analyzed from different depths of the kerosene tank. Combined with the pipeline layout, the hot upside and the cold downside of the kerosene stratification are induced by the stagnation area existing in the upside during the kerosene cooling flow. Comparing the bubble with the pump reflux, the results show that the bubble has a good effect in eliminating the vertical thermal stratification of the kerosene, and the pump reflux turns out to be of no effect. To accurately forecast the temperature of kerosene after cooling, different methods of temperature regulation are used in multiple experiments, and the target temperature calculation model of the kerosene regulating process is established, which could be used to judge the stop time of the kerosene cooling. The bubble and the temperature regulation calculation model has been successfully applied in TZ-1 launch mission, and effectively guarantee the temperature quality of the kerosene propellant.