Numerical Investigation of the Temperature Distribution of a Solar Cavity Receiver Wall Using Finite Element Method

The finite element method has been proved to be the effective numerical tool for finding approximate solutions of two or even up to three-dimensional governing differential equations. It has an ability to handle irregular geometries and any number of complicated boundary conditions with ease. The cavity receiver of a solar thermal system operates at a very high temperature. It may also cause larger energy losses from the cavity by radiation as well as convection as dominant modes of heat transfer. The collection efficiency depends on the useful heat gained by the working fluids, which is influenced by the receiver-energy losses. The energy losses from the cavity receiver depend on the cavity wall surface temperature. The temperature variation depends on the boundary conditions as well as geometrical orientation of the receiver. The knowledge of temperature distribution is one of the important factors needed for evolving an ideal design of a cavity receiver. The present chapter focuses on the design aspects as well as approximate estimation of wall temperature distribution of a cavity receiver of cylindrical shape. The step by step formulation of the problem using finite element method is also presented in the present chapter. The computational domain of a receiver wall is discretised into number of triangular elements and the simultaneous equations are solved using MATLAB.