皮托管测量影响因素分析 I. 检测杆与安装角的影响

在现场使用中,皮托管不可避免地会偏离其标准使用条件,从而引起附加误差.针对不同型号的皮托管进行了较系统的试验,旨在研究检测杆和安装角对皮托管测量的影响.结果表明,在被测流速较低时,皮托管检测杆直径的大小对全压的测量影响较小,且测量值误差也较小;在皮托管安装角不超过±10°的范围内,流速测量误差为±2%;较小管径检测杆的测量值存在非零安装角时,受流速的影响比较小.这些结论为优化皮托管的测量提供了指导.

On the influencing factors in a Pitot tube measurement I. Influence of air horn and mounting angle

Used in working situations, extra errors are inevitably added to the measurement results of a Pitot tube due to deviations from its standard usage conditions. Aiming at investigating how the air horn and mounting angle affect a Pitot tube measurement, experiments were carried out on various Pitot tubes in this paper. The results show that, first of all, in the lower velocity measured, the diameter of an air horn had little influence on the total pressure and the measurement results had small errors compared with the reference values. Secondly, the extra errors were ±2% when the mounting angle ranged from -10° to 10°. Thirdly, the measured values of an air horn with smaller diameter were hardly affected by the flow velocity even if there existed non-zero mounting angles. These findings could provide guidance for optimizing the performance of a Pitot tube.