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通过实验测定了螺旋槽管内的结垢情况,并与光滑管进行了比较.实验中定时测定了螺旋槽管和光滑管的传热阻力,分别描绘了螺旋槽管和光滑管的结垢曲线.实验结果显示轧槽管的污垢热阻约为光滑管的0.52~0.88倍.与光滑管相比,螺旋槽管具有较低的污垢热阻,且热阻与时间的关系能够用污垢曲线模型具有蕴育期来解释.实验结果显示螺旋槽管的污垢渐近线值约为光滑管的52%~70%,并且污垢热阻随着流速增大显著减小,螺旋槽管的污垢热阻是流速的强函数.当其它参数不变,流速从0.25 m/s增大到0.75 m/s时,污垢热阻减小到原来的66.7%.努塞尔特准数值约为光滑管的1.8倍.
The fouling in the spiral fluted tube was measured experimentally and compared with that of the smooth tube.The heat transfer resistance between the spiral fluted tube and the smooth tube was measured regularly in the experiment, and the fouling curves of the spiral fluted tube and the smooth tube were respectively plotted. The experimental results show that the fouling resistance of the grooved tube is about 0.52 ~ 0.88 times that of the smooth tube.Compared with the smooth tube, the spiral groove tube has a lower fouling resistance, and the relationship between the thermal resistance and the time can be represented by the fouling curve model The results show that the asymptotic value of the spiral tube is about 52% ~ 70% of that of the smooth tube, and the fouling resistance decreases with the increase of the flow rate. The fouling resistance of the spiral tube is Which is a strong function of the velocity of flow. When the other parameters are unchanged, the fouling thermal resistance decreases to 66.7% when the flow velocity is increased from 0.25 m / s to 0.75 m / s. The Nusselt quasi-value is about 1.8 times that of the smooth tube .