Comparative Study of an Evacuated Tube with a Copper Heat Tube and a New Receiver for Air Heating by a Parabolic Trough Collector

The investigation of the performance traits of two types of thermal receivers used in parabolic sunray air heaters is the primary goal of this work. At the focal length of a parabolic trough, one evacuated tube receiver, with a copper heat tube placed in it (case 1), and one with a pyramidal square receiver and fins (case 2), was used to compare the effectiveness of sunray air heaters. The temperatures at the heat exchangers’ output and the efficiency of the receiver are used to evaluate the collector. It has been noted that the case 1 heat exchanger outperforms the case 2 heat exchanger in terms of system performance. When case 1 and case 2 are used, the maximum output temperatures of the air at 0.015 kg/s are 53 ℃ and 47 ℃, respectively, at 950 W/m2. In the case of heat exchanger 1, the efficiency of the solar air heater ranges from 11% to 12%, while the increase is from 8.9% to 9.6% for the heat exchanger of case 2.