水蒸气压强对空气管内强制对流传热系数的影响

Effect of vapor pressure on forced convection heat transfer coefficient of air in tube

研究了圆形直管内空气强制流动被水蒸气加热时的对流传热系数,考察了加热水蒸气压强对湍流区的对流传热系数测定的影响和试验的重现性,并对结果进行关联、与经验式做比较及分析。结果表明:水蒸气压强对测定空气对流传热系数有显著影响,试验结果与经验值相比,偏小约9.0%;必要时应考虑具体数值的修正;试验在同一台装置上的重复性和在不同装置上的重现性均高。

The study focused on the convection heat transfer coefficient of air forced flow when heated by water vapor heating inside the circular straight tube, investigating the effect of the pressure of heating water vapor on determining convection heat transfer coefficient of the turbulent flow region and the reproducibility of the experiment. The results were correlated and compared with the empirical formula and analyzed. The results show that the vapor pressure has a significant influence on the determination of air convection heat transfer coefficient, with the experimental result about 9.0% smaller than the empirical value. The specific numerical value should be considered to revise if necessary. It is also found that the experiment has high repeatability on the same device and high reproducibility on different devices.