Numerical Study On Coupled Heat Transfer And Resistance Characteristics Of Plate Heat Exchanger

Plate heat exchanger is a heat transfer equipment that realizes heat exchange between cold and hot fluids.It has the advantages of high heat transfer coefficient,small resistance coefficient,compact structure and low operating cost.It is widely used in aerospace,petrochemical,refrigeration and low temperature.It plays a huge role in industrial production.In this paper,the plate heat exchanger is taken as the research object,and the coupled heat transfer model of the plate heat exchanger with two hot and cold channels is established.The heat transfer performance,resistance performance and comprehensive heat transfer performance of the plate under different structural parameters vary with the Reynolds number.Finally,the heat transfer and flow resistance performance of the two types of plates are compared,and it is concluded that the comprehensive heat transfer performance is the best Good plate.The main conclusions of this study are as follows:The effect of herringbone plate heat exchanger on heat transfer and flow resistance performance under different corrugated structure parameters was studied.With the increase of the corrugation inclination β,the Nusselt number Nu first increases and then decreases,the frictional resistance coefficient f increases first and then decreases,and the area quality factor j/f first decreases and then increases;the larger the corrugation spacing λ,the Nusselt number Nu is the smaller,the frictional resistance coefficient f is the smaller,and the area quality factor j/f increases continuously;the larger the corrugation height H,the larger the Nusselt number Nu,the larger the frictional resistance coefficient f,The area quality factor j/f decreases continuously.The effect of bubbling plate heat exchanger on heat transfer and flow resistance performance under different concave-convex structure parameters was studied.When the concave-convex inclination angle α gradually increases,the Nusselt number Nu first increases and then decreases,the frictional resistance coefficient f increases first and then decreases,and the area quality factor j/f first decreases and then increases,that is,the concave-convex inclination angle When α=20°,the area quality factor j/f is the largest.With the increase of the concave-convex spacing d,the Nusselt number Nu gradually decreases,the frictional resistance coefficient f also decreases gradually,and the area quality factor j/f gradually increases.With the increase of the cell width b,the Nusselt number Nu gradually increases,the frictional resistance coefficient f also increases gradually,and the area quality factor j/f gradually decreases.By comparing the variation law of Nusselt number Nu,frictional resistance coefficient f and area quality factor j/f with Reynolds number Re of the two types of plates.It is concluded that when the Reynolds number Re increases continuously,the Nusselt number Nu of the two plate types also increases continuously,and the Nusselt number Nu of the bubbling plate is larger than that of the herringbone plate,The frictional resistance coefficient f decreases gradually with the increase of Reynolds number Re,and the frictional resistance coefficient f of the herringbone plate is larger than that of the bubbling plate;the area quality factor j/f decreases slowly with the increase of Reynolds number Re,and the area quality factor j/f of the bubbling plate is greater than that of the herringbone plate,that is,the comprehensive performance of the bubbling plate is better than that of the herringbone plate.