对R22与R417A在水平光滑管和2种不同几何参数的内螺纹管中的流动沸腾换热进行实验研究,分析比较了2种制冷剂流动沸腾换热性能的差异.实验结果表明:R417A的换热性能与R22相比有一定程度的降低,其降低程度因质量流速、干度及换热管参数的不同而异,质量流速越小,R417A换热性能的降低越严重；在x＜0.6的较低干度区内,光滑管中R417A的换热系数比R22约降低了20％ ～ 40％,内螺纹管中的降低幅度更大,几乎达到50％～60％,在x＞0.6的较高干度区内,不同换热管中R417A换热系数的降低幅度较为相近；光滑管中R417A换热系数的降低幅度受干度影响较大,且随干度的增加而增大,内螺纹管中的降低幅度受干度影响较小；强化管对换热的强化效果越好,R417A换热系数的降低幅度就越大.%The experimental study was carried out on heat transfer of R417A and R22 flow boiling inside horizontal smooth and two internally grooved tubes with different geometrical parameters, the difference of heat transfer performance for R417A and R22 was analyzed and compared. The results indicate: Compared to R22, the heat transfer performance for R417A decreases, and this decrease associates with mass flux, vapor quality and geometrical parameters of test tube, the lower mass flux, the more serious decrease of heat transfer performance for R417A; At lower vapor quality region for x <0. 6, the heat transfer coefficients for R417A in smooth tube decrease 20% ~40% than R22, and this decrease is more serious in internally grooved tubes, almost reaches 50% ~ 60% , at higher vapor quality region for χ >0. 6, the decrease of heat transfer coefficients for R417A in different tubes is close to each other. The influence of vapor quality on decrease of heat transfer coefficients for R417A is bigger in smooth tube and is smaller in internally grooved tubes, the decrease augments with the increasing vapor quality in smooth tube; The better effect of heat transfer enhancement by internally grooved tubes, the bigger decrease of heat transfer coefficients for R417A.
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