板式热交换器流动分布的理论分析与实验研究

Experimental and Theoretical Study on the Flow Distribution of Plate Heat Exchanger

板式热交换器和相同形状波纹槽道的流阻和传热有较大的差距 ,通过流型观测发现板式热交换器内的流量分配不均匀 ,偏流的存在降低了板式热交换器的传热性能 ,增大了流阻 .在压力降测试的基础上 ,提出了单元流路分析的原理和方法 ,能够定量计算板式热交换器内的流量分布 ,并计算了BR10和BR12两种板式热交换器 .计算表明 ,进出口段的波纹形式能显著地影响板式热交换器内的流量偏差 .误差分析验证了单元流路分析结果的可靠性 .

Comparing the heat transfer and flow resistance characteristics of plate heat exchanger (PHE) with those of the identical form of corrugated duct, we find the difference is great. This paper gave forth the reason is the flow rate poor distributed in the PHE. The partial flow is visualized by experiment. Meanwhile, a theory and methodology of the unit flow path analysis was given to calculate the flow rate distribution in PHE, and the flow rate distribution in BR10 PHE and BR12 PHE are calculated and analyzed as an example. Analysis shows that a reasonable design of the form of inlet and outlet, and use diagonal flow can reduce the partial flow obviously. Also, error analysis verified the reliability of the theory and the calculation method of the unit flow path analysis.