Study On Heat Transfer Performance Of Spiral Ribbed Plate Collector

With the change of global energy structure,new clean energy represented by solar energy is widely used in heating,heating and cooling.Flat plate collector is the core component of solar thermal conversion system,and how to improve the heat conversion efficiency has become a hot issue in this field in recent years.This paper systematically analyzes the research progress of plate collectors according to domestic and foreign literature,and summarizes the methods and existing problems of heat collectors to enhance heat exchange.On this basis,a flat plate heat collector with spiral ribs is designed,which can increase the heat exchange area and fully disturb and mix the air flow through conduction,which further strengthens the heat exchange effect.Establish a mathematical model for flow and heat transfer in a spiral finned flat plate collector,and conduct numerical simulation analysis.Compare and analyze the surface temperature,inlet and outlet pressure difference,friction resistance coefficient,average Nu of the collector,and comprehensive thermal performance factor of the collector for fins with different structural parameters(rib height h,rib diameter d,guide vane width b,and spiral pitch p).Finally,it is clarified that compared to the 50 mm heat exchange channel,the optimized rib structure parameters are: h=38mm,d=25mm,b=16mm,p=160mm,and the diversion angle is 33.92 °.Based on the optimized rib structure,an orthogonal experimental method was used to analyze the influence of rib spacing and ultimately determine the optimized rib spacing of the collector.The effects of ambient temperature,solar radiant intensity intensity,inlet flow rate and heat conductivity of the heat collector on the heat transfer characteristics of the collector are analyzed.