水平微圆管内R22和R410a凝结压降的实验研究

R410a是一种被广泛看好的R22替代物,研究R410a的凝结压降特性对开发适用此种制冷工质的凝结换热设备有重要意义。搭建了微细尺度凝结压降实验台,实验研究了R22和R410a在内径为0.941mm水平不锈钢圆管内饱和温度为40℃、质量流速为200-1000 kg/m^2.s、干度为0.2-0.8时的凝结压降特性。实验结果表明：凝结压降随着质量流速的增大而增大,在较高干度时更加明显。与R22相比,R410a的凝结压降在较低干度和质量流速时与R22相当,在较高干度和较高质量流速时明显低于R22。

Experimental Investigation on Pressure Drop of R22 and R410a during Condensing Process in Microtubes

R410a is known as one of the substitutes for R22 and it is important to study the pressure drop of R410a during condensing processes. A test rig was established to measure pressure drop in micro scale and characteristics of pressure drop of R22 and R410a in a horizontal stainless round tube with an inner diameter of O. 941 mm during condensing processes were investigated experimentally at the saturation temperature of 40%. The mass flux varied within the range of 200- 1000 kg/m^2 s and the vapor quality 0. 2- 0. 8. The experiment results indicate that pressure drop increases with mass flux and vapor quality and more obviously in high vapor quality region. The pressure drop of R410a is equivalent to that of R22 at low vapor quality and mass flux but obviously lower than that of R22 at higher vapor quality and mass flux.