EXPERIMENTAL PERFORMANCE EVALUATION OF PARABOLIC TROUGH SOLAR COLLECTOR FOR STEAM GENERATION

Abstract

This paper presents the experimental performance evaluation of a parabolic trough solar collector (PTSC) for hot water and low enthalpy steam generation. A prototype of a PTSC with a 90° rim angle and a concentration ratio of 20 was constructed using mild steel as a support of the reflective mirror strips pasted on the bent sheet that formed the trough. The receiver is a copper pipe of circular cross-section, contained within glass envelope made from borosilicate material. The investigation was carried out at Department of Mechanical Engineering, Bayero University, Kano-Nigeria climatic conditions (12.05°N, 8.53°E) during selected days of the months of October, November, February, March, April, and May. The tests were conducted using a suitable solar collector test standard and the efficiency curve for the PTSC was estimated. In the performance analysis of the PTSC, the effects of collector inlet temperature, solar intensity and useful energy gain on the mass flow rate of water as a working fluid were investigated. The results show that the equation for thermal efficiency is comparable to similar collectors available in the literature; the intercept is 0.532 and the slope -0.1097. The highest and lowest temperatures of 133.5°C and 56.2°C were obtained in the month of April and October respectively. These temperatures obtained established the technical feasibility of using PTSC in Kano-Nigeria, for industrial process heat applications requiring thermal energy at temperatures up to 133.5 ºC