Thermal performance evaluation of alumina-water nanofluid in an inclined direct absorption solar collector (IDASC) using numerical method

In this paper, thermal performance of a nanofluid in an inclined direct absorption solar collector (IDASC) is evaluated using a hybrid of finite difference method (FDM) and Differential Transformation Method (DTM) called Hybrid FDM-DTM. After presenting the governing equations and solving by hybrid method, the accuracy of results is examined by fourth order Runge-kutta numerical method. Alumina/water nanofluid is considered as the working fluid in the collector and two boundary conditions are defined for the collector base; a constant temperature and convection heat transfer. The second condition leads to insulated base when the coefficient is assumed to be zero. For both boundary conditions, the problem is analyzed and collector efficiency is calculated. Results confirm that to reach an efficient collector, nanoparticles volume fraction, convection coefficient and base temperature should be considered in maximum possible values.