水平双侧强化管传热性能测定的新方法及实验研究

针对水平双侧强化管的传热性能测定提出了一种新的方法,称之为水环实验法,其基本过程是:在自行设计的套管换热装置中,通过实验得到缠绕铜丝的光滑传热管管外环形小通道内单相水传热关联式,应用该式通过热阻分离的方法得到一种新齿形内螺纹双侧强化传热管的管内传热关联式。同时研究了对于该管水在管内对流和制冷工质R123在管外凝结的传热情况,并采用水环实验法和常规热阻分离法对实验数据进行处理。经过实验研究和理论分析表明:本文的方法所得到的管内外传热系数较常规热阻分离法更加准确。

New Method for Testing the Heat Transfer Performance of Horizontal Doubly-enhanced Tubes and the Experimental Investigation

In order to test the heat transfer performance of horizontal doubly-enhanced tubes, a new method called water-ring method was put forward. The basic process was that the annulus side correlation of the smooth heat transfer tube wrapping copper wire spirally was firstly obtained by a series of experiments in the self-designed annular tubes test bench. Then the convective heat transfer resistance of the doubly-enhanced tube with the same form of copper wire could be separated from the total thermal resistance to fit out the heat transfer correlations of the inside tube. The condensation surface heat transfer coefficients of refrigerant R123 and the convection surface heat transfer coefficients of water were measured by using the correlations. The experimental study and theoretical analysis shows that the result using water-ring method is more accurate than the normal thermal resistance separation method.