Modification of heat storage system involving Trombe wall in existence of paraffin enhanced with nanoparticles

Abstract

Unsteady flow within a solar system with the Trombe wall technique has been scrutinized in current paper. To enhance the productivity of the classic Trombe wall, the paraffin layer has been combined with other layers (insulation, absorber, and concrete layers). The type of paraffin is RT18, and the conditions of the surrounding in the simulation have been selected according to a sunny day in autumn. Adding alumina nanoparticles into RT18 makes the conduction mode of paraffin enhance. The regime for the air zone is turbulent, and circulation via buoyancy force makes the domain warmer, therefore, the k-ε RNG technique was utilized for this region. The heat loss from glass due to radiation and convection has been involved in modeling. A verification test has been done not only in view of modeling of classic Trombe wall but also for modeling of melting of paraffin in ventilation application. The time step and grid size were optimized to reduce the cost of computing. A comparison of results for 3D simulation and 2D modeling indicates that there is no sensible change, therefore, considering the 2D model is logical. Among various scrutinized positions of the PCM layer, the first case (PCM near the absorber) has a greater liquid fraction. Moreover, if the PCM layer has been utilized in the middle, the minimum heat loss from the walls can be obtained.