Microscale vapor compression refrigeration

消费电子和商业电子的快速发展在很大程度上是由于工程师和物理学家能够将数百万电子设备集中到邮票大小的集成电路中。密集的电子设备也会导致高浓度的热通量，这反过来又会导致温度升高和产品可靠性急剧下降。传统的冷却程序，例如使用风扇迫使空气流过热组件，是有效的，但仅在低功耗应用中。 随着电力需求的增加，电子设计师被迫重新考虑冷却策略，包括使用微型制冷。这项研究计划将涉及传统蒸汽压缩制冷工艺的小型化，以生产微型（毫米级总尺寸）和迷你（厘米级总尺寸）制冷装置。 最佳的操作条件将通过开发基本模型来实现，该模型用于基于系统中熵产生的最小化来估计传热和压降。 工作原型将使用计算机数控（CNC）机器的微型单位和微机电系统（MEMS）技术的微型单位。 将对原型进行台架测试，以表征一系列操作条件下的热性能。 用于电子冷却的更小、更有效的散热设备的开发将对包括计算机、汽车电子和电动机在内的各种产品的发展产生深远的影响。

The rapid evolution of consumer and commercial electronics has been attainable in large part due to the ability of engineers and physicists to concentrate millions of electronics devices into integrated circuits the size of a postage stamp. Densely populated electronics devices also lead to high concentrations of heat flux which in turn leads to elevated temperatures and a dramatic decrease in product reliability. Traditional cooling procedures, such as using a fan to force air over hot components, are effective but only in low power applications.  As power requirements increase, electronics designers are forced to rethink cooling strategies, including the use of microscale refrigeration. This research initiative will involve the miniaturization of a conventional vapor compression refrigeration process to produce micro (overall dimensions of millimeters) and mini (overall dimensions of centimeters) refrigeration units.  Optimum operating conditions will be achieved by developing fundamental models for estimating heat transfer and pressure drop based on a minimization of entropy production in the system.  Working prototypes will be built using Computerized Numerically Controlled (CNC) machines for the mini-scale units and Micro Electro-Mechanical Systems (MEMS) techniques for the micro-scale units.  The prototypes will be bench tested to characterize the thermal performance for a range of operating conditions.   The development of smaller, more effective heat dissipation devices for electronics cooling will have a profound influence on the evolution of a wide range of products, including computers, automotive electronics and electric motors, to name a few.