The purpose of this study was to identify the optimal construction of an averaging pitot tube and measure flows typical in building ventilation, considering low-velocity flows. The construction should be simple to implement in variable air volume (VAV) controllers. This paper presents mostly novel constructions, which have not been tested before, and fills the existing gap in low-velocity measurements, which is important considering the correct control with airflow reduction in the VAV system. Eleven constructions based on a circular section of the basic element were chosen. Empirical studies were conducted to determine the aerodynamic properties. The tests were conducted within a typical velocity range in ventilated systems (0.6–7.5 m/s), based on measuring the pressure difference at suitable locations on the upstream and downstream surfaces. The magnification factor (m) was obtained and compared. Sensors consisting of two parallel and slightly separated tubes from each other with upstream and sideward ports on the inner side of the sensor were characterised by a constant and highest value of the factor m (approximately 2.0). These sensors yielded approximately 25% higher values of m than the lowest values. The best sensor constructions among the tested structures were the variants with two parallel tubes with front and side ports from the inner side of the sensor. The application of narrowing and placing of the side port enabled a stable operation in the highest range of velocity.

本研究的目的是确定平均皮托管的最佳结构，并在考虑低速流动的情况下测量建筑物通风中的典型流量。该结构应该很容易在可变风量 (VAV) 控制器中实现。本文主要介绍了以前未经过测试的新颖结构，并填补了低速测量中的现有空白，这对于 VAV 系统中气流减少的正确控制非常重要。选择了基于基本元素的圆形截面的 11 种结构。进行了实证研究以确定空气动力学特性。测试是在通风系统的典型速度范围 (0.6-7.5 m/s) 内进行的，基于测量上游和下游表面合适位置的压力差。m ) 得到并比较。由两个平行且略微分开的管组成的传感器在传感器内侧具有上游和侧向端口，其特征在于系数m的恒定和最高值（约 2.0）。这些传感器产生的m值比最低值高约 25% 。测试结构中最好的传感器结构是具有两个平行管的变体，前部和侧部端口来自传感器的内侧。侧端口变窄和放置的应用使得在最高速度范围内稳定运行。