Investigating the effect of mass flow and inlet air temperature To the solar flat collector on its thermal performance

Abstract

The aim of this study was to investigate the effect of mass flow and inlet air temperature on the solar flat collector on its thermal performance. For this purpose, a collector measuring one meter by one meter, with variable mass flow (zero to one hundred and twenty-eight kilograms per hour) and the temperature of the air entering the collector, in two cases, equal to the temperature of the open air equal to zero degrees Celsius And once considered the return temperature of the building is equal to twenty-five degrees Celsius. The results show that the thermal efficiency of this collector sample increases with increasing flow rate in both cases. If free air enters the collector at zero temperature of one hundred and twenty-eight degrees Celsius per hour, its thermal efficiency will reach ninety-three and eight-tenths of a percent, but the temperature of the air leaving the collector is so low that in this case The solar collector can only be used to preheat the air needed for ventilation. If the air returning from the building enters the collector with a flow rate of one hundred and twenty-eight kilograms per hour and a temperature of twenty-five degrees Celsius, its thermal efficiency is fifty-five and three tenths of a percent, and the temperature of the air leaving it is twenty-nine. It will be half a degree Celsius. If the mass flow rate of this collector sample is sixteen to thirty-two kilograms per hour, the temperature of the exhaust air will change, in the first case, between forty to fifty degrees and for the second case, between twenty-five to forty-two degrees Celsius will do. If this solar collector sample is used to preheat the air required for ventilation, the thermal performance and efficiency will be in the best condition.