Small scale refrigeration system for electronics cooling within a notebook computer

Abstract

The cooling of high power components in notebook computers is uniquely challenging due to space constraints that limit the size of the thermal solution. As a result, for some applications, a method of inserting a negative thermal resistance into the heat flow path may be required in order to achieve higher component powers. In this paper we describe a small-scale refrigeration system for the cooling of high power components in notebook form factors. The small-scale refrigeration system includes a compressor, cold plate, condenser, and throttling device. These components are designed for a vapor-compression cycle with iso-butane as the working fluid. All of these components are designed such that the entire system can be incorporated within a notebook form factor. In order to achieve the targeted performance, the cold plate and condenser contain microchannels to efficiently transfer heat to and from the refrigerant. Prototypes of each of the components were built and tested in order to assess their individual performance. A complete form factor loop was also built and tested in order to determine overall system feasibility and performance. The test results show that the targeted performance of the system (COP > 2.25) is achievable in this form factor at the moderate temperature rise expected in this application