ABSTRACT

NUMERICAL SIMULATION OF THE ACTIVE

MAGNETIC REGENERATIVE REFRIGERATOR

by

Dr. Bakhodirzhon M. Siddikov

A time-dependent one-dimensional model of the active magnetic regenerator (AMR) is developed as a highly nonlinear system of partial differential equations. The adequateness of the model is tested by assuming there is no magnetization or demagnetization, which is the case of a passive regenerator. Highly dependable approximation functions for the physical properties of the heat transfer fluid (water) and magnetic material (gadolinium) are obtained. The technique of calculation of values of the thermo-magnetic function of the magnetic material through the values of the adiabatic temperature change of the material, is worked out and a good approximation for is obtained. The numerical scheme for solving the active magnetic regenerator model is developed and its performance analyzed for stability and convergence. The optimal design parameters of the active magnetic regenerator are obtained as a result of solving an optimization problem.