Mathematical Modeling and Thermal Analysis of Evacuated Flat Plate Collector in Pakistan

Abstract

Energy plays a vital role in the development of a country. In the industrial sector water heating applications of different temperature ranges from low to medium use a major portion of final energy consumption. The Energy Sector is now facing a demand-supply gap that must be bridged, as well as an improvement in the energy mix for lower-cost supply. Solar energy is, without a question, one of the most suitable and broad solutions to the present increasing energy demand and resulting economic and environmental challenges. Conventional solar systems, on the other hand, suffer unbeatable hurdles that compromise their technical performance and economic viability. To address these issues, more emphasis is being placed on the use of solar thermal collectors as a cost-effective heat transmission technique. This paper describes an evacuated flat plate collector with a surface area of 4 m2 using a water-glycol mixture is a working fluid that circulates inside the copper tubes with mass flow rates of 0.03, 0.0336, and 0.0504 kg/s. Vacuum is created inside the enclosure of the collector by using a vacuum pump for the reduction of convective losses between absorber and glass cover. Program code developed in MATLAB was simulated with design conditions of the EFP collector model and input climatic data obtained from MHP equipment positioned at USPCAS-E, NUST, Islamabad, Pakistan. The current study also comprises parametric sensitivity analysis and model validation of EFP collectors. Using EFP collector results in 15°C rises of the absorber temperature and 8°C rises in fluid outlet temperature when compared to the FP collector without vacuum. The maximum thermal efficiency of evacuated flat plate collector observed is 0.78.