不可逆双谐振通道能量选择性电子制冷机热力学性能优化

Thermodynamic performance optimization for irreversible double-resonance energy selective electron refrigerator

建立了考虑线性热漏的不可逆双谐振通道能量选择性电子(energy selective election,ESE)制冷机模型,导出了制冷机制冷率和制冷系数的表达式,应用有限时间热力学理论研究了系统制冷率与制冷系数最优性能,通过数值计算,详细分析了热漏、能量宽度、能量间距等设计参数对ESE制冷机最优性能的影响。研究发现,系统的制冷率和制冷系数都会随热漏的增加而减小;给定能量间距时,制冷率和制冷系数都会随能量宽度的增加而先增大后减小,存在最优的能量宽度使制冷率或制冷系数达到最大值;给定能量宽度时,制冷率和制冷系数会随能量间距的增加而先增加后减小,存在最优的能量间距使制冷率或制冷系数达到最大值。合理地选取能量宽度、能量间距等参数,可以使不可逆的双谐振ESE制冷机设计于最大制冷率或最大制冷系数的状态。

A model of an irreversible double-resonartce energy selective electron （ESE） refrigerator with linear heat leakage was established. The expressions of cooling load and coefficient of performance （COP） of the refrigerator were derived. The optimal cooling load and COP performance of the irreversible ESE engine were analyzed by using the theory of finite time thermodynamics. The effects of heat leakage and design parameters such as resonance width and energy spacing on the optimal performance of the system were discussed in detail by numerical calculations. It is shown that both cooling load and COP decrease as heat leakage increases. For fixed energy spacing, the cooling load and COP first increase and then decrease as resonance width increases; there exists the optimal resonance width which leads to the maximum cooling load or COP. For fixed resonance width, the cooling load and COP first increase and then decrease as energy spacing increases; there exists the optimal energy spacing which leads to the maximum cooling load or COP. By properly choosing the values of the design parameters such resonance width and energy spacing, the irreversible double resonance ESE refrigerator can be designed to operate at maximum cooling load or maximum COP point.