Modelling and Experimental Study for the Design and Development of the Heat Receiver Tube for Solar Concentrator

Abstract

Solar energy is the most abundant form of renewable energy. Solar energy has been used in different form from the ages. The variation in the solar incident radiation w.r.t. day time, location and season has attracted the researchers towards harnessing the solar energy in most optimum way. Harnessing energy in the form of heat has been of prime importance. Apart from flat plate collectors, solar concentrator technology (Linear Fresnel collector, parabolic dish collector, parabolic trough collector, heliostat field collector) are used to concentrate the solar radiation energy in order to enhance the heat transfer and system efficiency. Various types of a heat absorbing fluid (with higher thermal conductivity and specific heat) are used in a concentrator like Nano-fluid, water, Ethylene Glycol, Therminol VP-1 etc. Enhancing the heat transfer capacity has been prime research area in order to achieve higher efficiency and performance at reduced cost. Present work is focused on the design and development of a receiver tube that can be used for PTC. Thermal properties like thermal conductivity, specific heat capacity, and density and flow properties like mass flow rate, flow turbulence has been studied and evaluated for the optimum heat transfer for the variety of fluids. CFD modelling of a fluid flow and heat transfer using ANSYS FLUENT software has been performed. Solar radiation for input heat and K-ɛ model for the turbulence has been invoked in the present modeling work for simulating the various real time situations. There is a lack of sufficient and authentic data in the literature to validate the model. Thus, for the validation of the model, own setup of PTC is used to perform experiments with different fluid (Water, Ethylene Glycol, and Therminol VP-1) by varying the flow rate and by creating the turbulence in the fluid flow in pipe. Experimental result data and fluid properties are used for simulation and validation of the CFD model. The present work intends to develop a universal model that can be used to identify dimensions, suitable working fluid and flow properties to achieve optimum solar heat collection at a given geographical location.