热容燃烧室基于单点温度的热流测量方法研究 *

Method of Heat Flux Measurements Based on Single-Point Temperature Data in Heat-Sink Combustion Chambers

关键词:  火箭发动机  热容燃烧室  试验研究  热流密度

Key words:  Rocket engine  Heat-sink combustion chamber  Experimental research  Heat flux

摘要:

为了研究推力室内壁面与燃气间的传热特性，获得多喷嘴燃烧室内壁热载分布，从而为推力室设计及热结构分析提供参考，开展了热容燃烧室壁面热流测量方法研究。以位于距内壁一定距离位置的单点测量温度作为输入条件，文章提出了三种热流计算方法，并进行火箭发动机试验研究，得到了对应位置燃气对内壁的热流密度。可以看出，运用单点方法得到的热流密度与传统两点法结果符合较好，两者计算结果误差在10%以内。结果显示:不同点火时长工况下在同一位置相同时间点上重复性很好，在燃烧室圆柱段热流密度随着点火时长的增加而减小，而在喷管段变化规律则相反，热流密度随时间增加而增加。在提出的计算平均热流的三种方法中，热积累方法的计算结果最高，热平衡方法次之，瞬态法最低。在火箭发动机热容试验中，本文提出的方法可以用于测量燃烧室内壁面热流密度。

Abstract:

In order to investigate the heat transfer characteristics of the inner surface in thrust chambers and provide reference for the design of thrust chamber and the thermal-structural analysis， methods study was performed for heat flux measurements in the heat-sink combustion chambers. Using the temperature measured in a single point in one location， three methods of the heat flux measurements are proposed in this study. Experimental research is carried out to obtain the heat fluxes on the inner surface in a heat-sink thrust chamber by the proposed methods. It can be concluded that the results of transient heat flux obtained by the single-point method and the traditional two-point method match well in the verification tests， and the difference calculated by these two methods is less than 10%. The results show that good repeatability in the same time points and locations were achieved in conditions of different work time. For the transient variations of the heat flux， an inverse trend of transient heat flux with work time was observed in the cylindrical section and the nozzle section of the thrust chamber， respectively. For the proposed methods of the average heat flux， the minimum results are obtained by the transient single-point method while the maximum value is obtained with the heat accumulation method. For the experiments in the heat-sink rocket engine， the proposed method can be used to obtain the wall heat flux.