Numerical Optimization on the Ends Structure of Active Magnetic Regenerator

In a magnetic refrigeration system, an appropriate transitional section between the active magnetic regenerator and the heat exchanger effectively improves the flow mal-distribution at the both ends of regenerator, but also increases the dead volume and reduces the performance of the regenerator. This paper simulated the cooling performance of active magnetic regenerator under four different angles of transitional section, which is 15°, 30°, 45° and 60°, respectively. The optimal cooling performance was obtained by comprehensively considering the flow uniformity and dead volume at different lengths of regenerator and mass flow rates. Simulation results showed that when the length of regenerator is 20 mm, the optimum angle of transitional section is 30°; when the length of regenerator is 40 mm, 60 mm and 80 mm respectively, the optimum angle is 60°. When the length of regenerator is fixed, the influence of the flow uniformity on the system is more significant at larger mass flow rate. The selection of appropriate angle of transitional section is important for the structural design and improvement of an active magnetic refrigeration system.