对填充泡沫金属的圆管中R410A流动沸腾的两相流压降特性进行了实验研究.实验对象为两根内径13.8mm,分别填充5 PPI/95％孔隙率和10 PPI/95％孔隙率的泡沫铜的圆管.实验工况涵盖:蒸发压力995 kPa;质流密度30～90 kg·m-2·s-1;热通量5.9～16.5 kW·m-2；入口干度0.175～0.775.实验结果表明:泡沫金属显著增加制冷剂流动沸腾的压降,在入口干度为0.775,质流密度为90 kg·m-2·s-1时,内嵌10 PPI泡沫金属的圆管中的压降梯度达56 kPa·m-1；泡沫金属PPI越大,压降增加越多,相同工况下内嵌10 PPI泡沫金属圆管中制冷剂流动沸腾的压降是内嵌5 PPI泡沫金属圆管中的压降的1.2倍左右.根据实验数据开发了适用于填充泡沫金属的内径13.8 mm圆管中的流动沸腾的压降关联式,结果表明90％的预测值与实验值的偏差在±15％以内.%The two-phase pressure drop characteristics of R410A flow boiling inside tubes filled with metal foams were investigated experimentally. The test sections are two tubes of 13. 8 mm inner diameter filled with 5 PPI/95% porosity and 10 PPI/95% porosity metal foams separately. Experimental conditions include saturation pressure of 995 kPa, mass flux from 30 to 90 kg · m-2 · s-1 , heat flux from 5. 9 to 16.5 kW · m-2, and inlet vapor quality from 0.175 to 0. 775. The experimental results are as follows. Metal foams always increase the pressure drop of flow boiling, and the pressure drop reaches 56 kPa · m-1 at vapor quality of 0. 775 and mass flux of 90 kg · m-2 · s-1. The pressure drop increases with the value of PPI, and the pressure drop with 10 PPI metal foams can be as much as 1. 2 times that with 5 PPI metal foams under the same working condition. A pressure drop correlation for the 13. 8 mm tube filled with metal foams was developed based on the experimental data, and 90% of the predicted results agree with the experimental data within a deviation of ±15%.
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