Microscale vapor compression refrigeration

消费电子产品和商业电子产品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以百万计的电子设备集中到邮票大小的集成电路中。人口密集的电子设备也会导致热通量的高度集中，从而导致温度升高和产品可靠性的急剧下降。传统的冷却程序，如使用风扇迫使空气流过热部件，是有效的，但仅在低功耗应用中。随着电力需求的增加，电子设计人员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过程的小型化，以生产微型（总尺寸为毫米）和微型（总尺寸为厘米）制冷装置。通过开发基于最小化系统熵产生的传热和压降的基本模型来实现最佳操作条件。工作原型将使用计算机数字控制（CNC）机器和微型单元的微机电系统（MEMS）技术来构建。原型机将进行台架测试，以表征一系列操作条件下的热性能。更小、更有效的电子冷却散热设备的发展将对包括计算机、汽车电子和电动机在内的一系列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.