亚声速条件下总压探针临壁效应的数值研究

本文基于数值模拟的方法,研究了四种不同结构 (A型、B型、C型、D型)的总压探针在不同近壁距离条件下对流场及自身总压测量值造成的影响,并将数值模拟结果与文献实验结果对比。结果表明：相对近壁距离c/d越小,造成总压探针头部气流偏转角误差越大,总压探针的测量误差越大,总压损失系数最大值小于1%；当c/d>3,总压损失系数趋近于0,说明近壁距离大于3倍探针外径时临壁效应消失；在同一工况下,四种结构的总压探针测量值受到临壁效应的影响依次增大；被测流场流动均匀性减小,靠近总压探针支杆后方速度均匀度最小。

Numerical Investigation of Near Wall Effect of Total Pressure Probe Based on CFD under Subsonic Velocity

Based on the numerical simulation, the influence of total pressure probes of four different structures (type A, type B, type C, type D) on the flow field and their own total pressure measured values under different near-wall distances was studied, then verifies the numerical simulation results with the experimental results. The results show that: the smaller relative near-wall distance c/d is, the larger error of the airflow deflection angle of the front end of the total pressure probe is, the larger measurement error of the total pressure probe is, and the maximum value of total pressure loss coefficient is less than 1%. When c/d>3, the total pressure loss coefficient is close to 0, indicating that the wall effect fails when the near-wall distance is greater than 3 times the outer diameter of the probe. Influence of wall effect to measured values of the total pressure probes of the four structures are sequentially increased in the same condition. the uniformity of the measured flow field is reduced, and the velocity uniformity is the smallest behind the total pressure probe support rod.