Study On The Influence Caused By Temperature To A Thrust Test System For The Attitude Control Engine

As an important component of the attitude adjustment for modern space vehicles, the attitude-control rocket engine has been widely used in orbit and attitude control for aircrafts. To the aircrafts, direct influence to both the control precision and hit accuracy for target could be leaded by the working behavior of the attitude-control rocket engine. Therefore, it has great significance to research on the working performance for the attitude-control rocket engine.The multi-axis force test system based on the piezoelectric effect supplied a valuable test equipment along with a innovative approach to selection and styling for some rocket engine developed by Dalian University of Technology. The piezoelectric-dynamometer is the core in the test system which has some excellent advantages such as the good linearity, little hysteresis and high nature frequency, especially for the dynamic force measurement. However, the temperature and humidity dependence of the thrust dynamometer impose a limit to its application. Research on the temperature influence and propose a heat insulation or compensation method is contributed to improve the system test precision.In this paper, a single-dimension force test system based on the piezoelectric principle for one attitude control rocket engine is investigated. The finite element method (FEM) is presented and used to analyze the influence caused by the temperature to the thrust measurement system for rocket engines. It’s evident that the primary cause of the temperature influence to the test system leaded by the rocket engine is the thermal deformation located in the mechanical joint elements as well as the thermal stress generated from the deformation. A series tests have been conducted to emulate the heat conduction process when the engine firing, recording the test system output drift. Repeat the above experiments, and several groups static calibration experiments are conducted each time so as to obtain the temperature influence regularity and validate the accuracy of the theoretical analysis.According to the domestic&international analysis for the temperature compensation methods to the piezoelectric-based transducers, a test bolt gluing a strain-gauge is developed to monitor the thermal stress and compensate the voltages shift real-time. A deep research has been implemented for the test bolts. In order to verify that the test bolts can live up to compensate the test system voltages shift effectively and analyze the unstable factors of the compensation, many groups of experiments are conducted. Tests results demonstrate that it is possible to implement temperature compensation to the test system by the test bolts.