Modelling and Performance Analysis of U Type Evacuated Tube Solar Collector Using Different Working Fluids

This paper presents the mathematical modelling of a U type evacuated tube solar collector required for heating a working fluid. The developed mathematical model is used for predicting the outlet temperature and net heat gain by the working fluid. The model predictions are compared with experimental data and a good agreement is observed between them. Aqueous lithium chloride solution (LiCl-H2O), water and air are chosen as working fluids. The effects of working fluid flow rate and inlet temperature, collector length, ambient temperature and solar intensity on the performance of the system are investigated. It has been observed that collector length, working fluid flow rate and solar intensity have greater impact on performance of the collector. The working fluid inlet temperature doesn't have significant effect. Also, a detailed analysis on aforementioned working fluids is carried out for U type copper tube and the results are presented in this paper.