Experimental Study of Double Pass water passage in Evacuated Tube with Parabolic Trough Collector

Abstract

In this paper, a new design, fabricate and investigate the performance of the parabolic trough systems (PTC) by using double pass water passage in evacuated tube technology. This system can be used for heating water in winter season without assistive devices. The double-pass method utilizing to improve thermal performance for PTC by increasing the path of water flow in the evacuated tube and then increase the rate of the outlet temperature. Besides, the evacuated tube was used to decrease the thermal losses, which is caused an increase in thermal efficiency. The experiments were test and simulate the different solar radiation approximate to winter season and at many flow rates 0.00305, 0.0055 and 0.0083 kg/s. The higher temperature difference was 46 ° C at minimum mass flow rate 0.00305 kg/s. The maximum thermal efficiency was 69.7 % at 0.0083 kg/s.