Numerical simulation for structural parameters of flat-plate solar collector

Abstract

Based on finite volume method, the steady-state thermal performances of the flat-plate solar collector are studied by taking account of absorber plate thickness, collector tube spacing, collector tube length, collector tube diameter and insulating layer thickness. A physical model of gilled flat-plate solar collector is built, then the numerical simulation of the model is carried out and the numerical simulation results are compared and analyzed with experimental results. The results show that: Either increasing the absorber plate thickness or reducing the collector tube spacing can significantly improve the instantaneous efficiency of the collector. Setting the solar radiation intensity of 700W/m 2 and the environmental speed of 4m/s, when the absorber plate thickness increases from 0.1mm to 2.1mm, the collector instantaneous efficiency increases from 46.57% to 64.03%. When the collector tube spacing decreases from 170mm to 50mm, the collector instantaneous efficiency increases from 52.81% to 66.01%. Reducing the collector tube length and increasing collector tube diameter are both conducive to improve the instantaneous efficiency of the collector. When the collector tube length decreases from 2800mm to 1200mm, the collector instantaneous efficiency increases from 57.50% to 60.12%. When the collector tube diameters increases from 8mm to 20mm, the collector instantaneous efficiency increases from 56.18% to 63.97%. When the thickness of insulating layer is 30mm or more, increasing its thickness has no significant effect on improving the instantaneous efficiency of the collector. The research results are helpful to optimize the design parameters of the flat-plate solar collector.