直连式高空台试验中真空度与次流作用力校准的一种新方法

A New Measurement Method for the Action of the Secondary Flow and Vacuum in Direct-Connect ATF

针对某发动机高空台试验难以用加装堵板的常规方法测定真空度与次流作用力系数的情况,通过高空舱内冷却空气流动与高空舱内外压差对发动机测力系统作用的分析,介绍了高空舱内真空度和次流对发动机台架测量推力影响的作用机理,并从真空度作用力和次流作用力与发动机总推力的关系出发,经理论推导提出了一种确定真空度与次流作用力系数的新方法。该方法使用限制条件少,试验经济性好,具有较强的工程应用参考价值。

Regarding the pr,blems of measuring or calibrating both the vacuum-acting force and secondary flow-acting force coefficients with the accustomed method for a specific engine ATF test, through the analy- sis of the action on engine thrust measurement system of both air flow for cell-cooling and differential pres- sure between outdoor-cell and indoor-cell, a new measurement method is put forward which derived from their action mechanisms and the dependence relation between both acting force and engine gross thrust. Moreover, the new method can be used under lesser restricted condition and less cost in contrast to the rou- tine way. So there is certain reference value for engineering application.