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对非牛顿流体在小尺寸椭圆形通道内的层流受迫对流传热进行了实验研究。实验介质为1500Wppm的Carbopol-934中性水溶液。采用直接通电的方法对管壁四周等热流加热。结果表明,椭圆通道内,非牛顿流体Carbopol水溶液的换热强于牛顿流体水,约高出水50%左右,说明粘弹性流体在椭圆形通道内也产生二次流并能强化换热;与同种浓度的Carbopol水溶液在方形通道内的换热结果相比,椭圆通道内的换热高于方形通道。流体的压力降则不受粘弹性的影响,仍符合幂律流体的阻力系数关系式(f=16/Re*)。
The convective heat transfer of laminar flow over non-Newtonian fluid in a small elliptical channel was investigated experimentally. The experimental medium is 1500 Wppm Carbopol-934 neutral aqueous solution. The method of direct power supply heats the heat flow around the pipe wall. The results show that the heat transfer of Carbopol solution in non-Newtonian fluid is greater than that of Newtonian fluid in the elliptical channel, which is about 50% higher than that of water, indicating that the viscoelastic fluid also produces secondary flow in the elliptical channel and enhances the heat transfer. Compared with the result of heat exchange in the square channel, the elliptical channel has higher heat exchange rate than the square channel. The pressure drop of the fluid is not affected by the viscoelasticity and still meets the drag coefficient of power law fluid (f = 16 / Re *).