低温推进剂火箭发动机循环预冷方法研究

The Study of Circulating Chilldown Methods of Cryogenic Rocket Engine

预冷是低温推进剂火箭启动前的一个重要操作。目前国内外使用的预冷方式主要有排放式预冷和循环预冷。我国在氢氧发动机上一直使用的是排放式预冷。与排放式预冷相比 ,循环预冷能使射前操作和地面设备得到很大程度简化 ,因此 ,开展循环预冷研究十分必要。通过预冷耗液和稳定状态下的自然循环计算对循环预冷进行了理论分析。耗液计算以经典热力学理论为基础 ,循环计算应用了数值方法。数值计算中 ,以一维均匀两相流模型为基本模型。最后 ,通过模拟试验对计算进行了验证。得到循环预冷优于排放式预冷的结论 。

Chilldown of cryogenic rocket engine is a key operation to launch vehicle engineering. There are two main chilldown methods, discharge chilldown and circulating chilldown, and the former is always applied to domestic practice. Compared to discharge chilldown, circulating chilldown can make prelaunch operation and ground equipment more simplified, so research on circulating chilldown is necessary. This paper presents the theoretic analysis of circulating chilldown by calculating of chilldown propellant loss and flow recirculation at stabilization state. The classical thermodynamics theory is used in the calculating of chilldown propellant loss. While numerical calculating, based on one dimensionally homogeneous two phase flow model, is used in calculating of flow recirculation. The accordance between theory result and simulation test strongly demonstrates that circulating chilldown is superior to discharge chilldown, and that natural circulating chilldown program is feasible.