Design, enhanced Thermal and Flow efficiency of a 2KW active magnetic regenerator

The goal of the Danish ENOVHEAT project is to design and realize a high-efficiency magnetocaloric heat pump for the residential sector, based on the active magnetic regenerator (AMR) technology. Such a heat pump should have a coefficient of performance (COP) of at least 5, while giving a heating power of 1500 W over a temperature span of 25 K.

This paper explains several details of the device, such as the design of the magnet, the regenerator housing and the flow system. In particular, this paper investigates the best geometry for the regenerator bed to achieve a thermal and mechanically efficient housing to be used in the AMR system. Particular attention has been given to the reduction of the parasitic losses through the regenerator housing: both heat leaks between the magnetocaloric material (MCM) and an adjacent iron ring and the surroundings through a lid on top of the regenerator.

These quantities have been decreased by creating an embossment on the bottom surface of the regenerator and by placing a thin rubber sheet between the magnetocaloric material and the steel lid, respectively.