纵横式滞止罩设计方案研究

A design scheme of crossbar stagnation hoods

为提高总温传感器的测量准确度,以温度传感器滞止理论为基础,根据现有的设计经验合理设计一种与传感器探针配套使用的滞止罩,滞止罩采用纵横式结构设计。给出不同的测试环境及测温范围下滞止罩材料的选取建议;在气流温度为1 000 K、气流速度马赫数为0.5的条件下,利用CFD软件对在不同的滞止罩气流进出口面积比、不同的传感器探针探测长度、不同的主滞止室扩张角等3组条件下进行数值仿真,得到9种工况下滞止室内气流速度分布及探针表面的温度分布。经对比研究分析得到纵横式滞止罩对高速流动气体具有较好的滞止效果。

In order to improve the measuring accuracy of total temperature sensors, a stagnation hood of crossbar structure was designed to match with the sensor probe based on the stagnation theory of temperature sensors and current design experience. Recommendations were given to select stagnation hood materials under different testing conditions and measurement ranges. Under the conditions of 1 000 K-air flow temperature and 0.5 Ma-air velocity, CFD software was used for numerical simulation based on different air import/export area ratios of stagnation hoods,detection lengths of sensors,extending angles of primary stagnation chambers. In this way,the distribution of airflow velocity inside stagnation chambers and of probe surface temperature was detected under nine working conditions. A best design scheme for crossbar stagnation hoods was obtained through the above comparative analysis.