초록

The disclosure is directed to an active magnetic regenerator apparatus and method. Brayton, Stirling, Ericsson, and Carnot cycles and the like may be utilized in an active magnetic regenerator to provide efficient refrigeration over relatively large temperature ranges.

대표청구항 ▼

A method of refrigeration approximating a Stirling Cycle from an initial state of partial magnetization and utilizing two, two-phase external heat transfer fluids at temperatures about TC and about TH, the method comprising the steps of (a) magnetizing a body comprising one or more porous magnetic m

A method of refrigeration approximating a Stirling Cycle from an initial state of partial magnetization and utilizing two, two-phase external heat transfer fluids at temperatures about TC and about TH, the method comprising the steps of (a) magnetizing a body comprising one or more porous magnetic materials near but above their Curie temperatures, each at a temperature between about TC and about TH, flowing an internal heat transfer fluid at an initial temperature substantially TC through the porous material during a relatively higher magnetization of the body, any temperature increase caused by magnetization being compensated by temperature decrease due to thermal wave movement through the material, causing the internal heat transfer fluid to exit the body at a temperature slightly above about TH, which approximates isothermal magnetization; (b) continuing the internal heat transfer fluid flow into the body at about TC and decreasing the magnetic field slightly as average temperature within the body decreases, magnetization remaining essentially constant, approximating an isomagnetization temperature decrease within the body, the internal heat exchange fluid exiting the body at slightly above about TH; (c) reversing the flow of the internal heat exchange fluid at about TH through the body as demagnetization is compensated by temperature increase due to thermal wave motion in the body, the fluid exiting the body at slightly less than about TC, approximating isothermal demagnetization; and (d) continuing the reverse flow of internal heat exchange fluid through the body and increasing slightly the magnetic field therein to maintain constant magnetization as the average temperature of the body increases, the fluid exiting at slightly less than about TC, approximating an isomagnetization temperature increase; and (e) transferring heat from the internal heat exchange fluid to the two, two-phase external heat exchange fluids appropriately during the cycle to accomplish refrigeration.