基于热力学原理的风机性能测试方法研究

Research on test method of fan performance based on thermodynamics principle

建立了基于热力学原理的高压头风机性能测试方法的数学模型,同时研究了各测量参数误差对该方法精度的影响。计算与分析结果表明,风机进出口的温差及其测量精度对风机流量与效率精度的影响较大,风机进出口温差越大,计算精度越高。风机进出口温度与风机的压头及效率有关,当风机内效率为80%,进出口压差超过5 kPa时,风机进出口的实际温升将超过4 K,在温度测量误差绝对值为0.1 K时,风机流量以及效率计算的相对误差最大值均低于5%;如果风机的进出口压差在10 kPa以上时,同样温度测量误差条件下风机流量与效率计算相对误差最大值将低至2%以下。

The mathematic model of the performance test method of high-pressure head fan based on the thermodynamic principle is established. The influence of error of each measurement parameter the accuracy of the method is studied. The calculation and analysis results show that the temperature difference between the inlet and outlet of the fan and its measurement accuracy have a great influence on the flow rate and efficiency accuracy of the fan. The higher the temperature difference between the fan inlet and outlet, the higher the calculation accuracy. The temperature at the inlet and outlet of the fan is related to the fan head and efficiency of the fan. When the fan efficiency is 80% and the pressure difference between the inlet and outlet of the fan exceeds 5 kPa, the actual temperature rise at the inlet and the outlet exceed 4 K. When the absolute value of the temperature measurement error is 0.1 K, the relative error of the fan flow rate and efficiency calculation is less than 5%. If the inlet and outlet pressure difference of the fan is above 10 kPa, the maximum relative error of the fan flow rate and efficiency calculation under the same temperature measurement error condition will be as low as 2% or less.