用单斜热线探针研究离心叶轮出口三维流场的计算机辅助测量系统

COMPUTER-AIDED MEASURING SYSTEM OF THREE DIMENSIONAL FLOW FIELD WITH A SLANTED HOT WIRE

本文提出一套由单斜热线、等温型热线风速仪、探针移动及转动机构、多点采样脉冲分配器、采样保持器、模数转换器和IBM微型计算机组成的,用于测量叶轮出口三维流场和紊流特性的周期性多点采样测量系统。为了克服由于转速波动而引起的测点位置变化,本系统采用转速反馈的方法,即由转速对采样脉冲间隔修正的反馈系统,以减少测量误差。

A periodic muti-sampling measuring system which consists of a slanted single hot wire probe, the CTA system, a probe traverse mechanism, a muti- sampling pulse distributer, a sampling holder, an analog-digital converter and an IBM micro-computer is developed to measure three dimensional flow field and turbulence characteristics behind an impeller. In order to overcome the shift, in the relative position of the sampling points due to the fluctuation of rotating speed, a rotating speed feedback method is used in the system, i.e. a feedback system in which the sampling pulse intervals are modified by rotating speed is adopted to reduce the error.