In this problem, you will consider an "unusual" solid-state refrigeration device that achieves cooling by varying the magnetization of the working mate- rial (gadolinium sulphate octahydrate) at constant- pressure conditions. By contrast, most refrigeration cycles achieve cooling based on manipulating pres- sures of the working fluid. The device functions roughly as shown at the right wherein a paramag- netic wheel is rotated through different regions: i) a low-temperature region (12) • ii) a low-magnetic field region (23) iii) a high-temperature region (34) iv) a high-magnetic field region (4 → 1) In the figure, the thermodynamic state at the point of entry/exit from each region is shown.

In this problem, you will consider an "unusual" solid-state refrigeration device that achieves cooling by varying the magnetization of the working mate- rial (gadolinium sulphate octahydrate) at constant- pressure conditions. By contrast, most refrigeration cycles achieve cooling based on manipulating pres- sures of the working fluid. The device functions roughly as shown at the right wherein a paramag- netic wheel is rotated through different regions: i) a low-temperature region (12) • ii) a low-magnetic field region (23) iii) a high-temperature region (34) iv) a high-magnetic field region (4 → 1) In the figure, the thermodynamic state at the point of entry/exit from each region is shown.

Refrigeration and Air Conditioning Technology (MindTap Course List)

8th Edition

ISBN:9781305578296

Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Publisher:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Chapter28: Special Refrigeration Applications

Section: Chapter Questions

Problem 4RQ

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