Thermodynamics of active magnetic regenerators: Part II

Governing equations for the thermodynamics of an active magnetic regenerator (AMR) are used to analyze the performance of simplified cycles operating with idealized magnetocaloric material. An idealized material with a magnetocaloric effect that varies linearly with temperature is assumed. Results are presented for cases where balance and symmetry are equal to one (β=σ=1β=σ=1) and the refrigerant specific heat is constant. Under these conditions, the temperature distribution, cooling power, work rate, and efficiency are determined for various values of entrained fluid thermal mass (R). A set of sample results are presented for each case as a function of utilization, temperature span, and conductance. Results from the simplified thermodynamic theory are briefly compared to experimental results from the literature.

► Simplified relations for cooling power, work and efficiency of AMR cycles are derived.
► The performance potential of an idealized magentocaloric material is quantified.
► The impacts of parasitic thermal mass from entrained pore fluid are shown.
► The impacts of adiabatic temperature change and magnetic entropy change are discussed.
► Results are compared to reported experimental data.