Design and Three-Dimensional Simulation of a Solar Dish-Stirling Engine
Keywords:
Solar Stirling engine, Multi-facet dish concentrator, Cavity receiver, CFD simulationAbstract
Design and three-dimensional simulation of a solar Dish-Stirling (SDS) engine is currently performed. The design starts with the GPU-3 Stirling engine, which is originally built to generate power from the fossil fuel exclusively. The design is conducted through three subsequent phases. Firstly, several parabolic dishes with different rim angles and number of facets are investigated to optimally design the dish concentrator. Secondly, different relative positions of the receiver aperture to the dish focal plane are tested to reach the optimal position. The optical simulation of the solar concentration process is carried out using SolTRACE software. Finally, an optimal design for a cavity receiver that involves a new structure of the heater tubes is performed. The simulation of the engine with the designed receiver is implemented using the commercial CFD code ANSYS FLUENT. Having finished the design, a comprehensive energy analysis of the designed SDS engine is carried out. The results show that a nearly uniform temperature distribution of the heater tubes throughout the cycle is achieved. The overall thermal efficiency of the designed SDS engine is about 31.8 % at a DNI of 1000 W/m2.