Modeling of magnetization and demagnetization in magnetic regenerative refrigeration

A time-dependent model of temperature in magnetization and demagnetization processes is developed based on thermodynamic and heat transfer laws, material properties, and variable-field magnet parameters. Test results of a magnetic refrigeration test bed are compared with the model calculation. The model can be used to simulate optimum operating conditions and duty cycle of magnetic regenerative refrigeration. The effects of the thermal conductivity between the magnetocaloric material and the thermocouple on temperature measurements and thermal lag are presented.