污垢对换热器影响最小化策略研究

RESEARCH ON MINIMIZING INFLUENCE STRATEGY OF HEAT EXCHANGER SUBJECT TO FOULING

随着污垢在传热表面上积聚,传热热阻增加,传热效率降低;流道表面的粗糙度增加,摩擦系数增大,流体的流通截面积减小,引起流体流速增加,压力降增大。以污垢影响下换热器进出口流体属性的外在表现、流体流态参数作为分析对象,对计及污垢影响下的传热性能及管、壳程压降进行了分析及讨论,分析研究并确定了换热器污垢影响最小化策略,为工程师设计、操作换热器时降低污垢带来的负面影响提供理论依据。

With fouling accumulating on the heat transfer surface, heat transfer resistance increases, surface roughness and friction coefficient increase and the fluid flow section decreases, which lead to increase in pressure drop of heat exchanger. This article analysed fluid flow attribute of heat exchanger subject to fouling, based on the inherently linear nature between outlet and inlet temperatures of heat exchanger. The impact of fouling on heat transfer and pressure drop in tube and shellside was analyzed and discussed. Strategies of minimizing fouling impact were introduced, which provide the theoretic gist for alleviating the effect of fouling.