Groove-enhanced Integral Micro-channel Development
Project funding: $58,455, January 2008 through December 2008
Over the past several decades, transistor sizes have decreased exponentially, resulting in growing power losses in more concentrated volumes. If this current trend holds, the thermal dissipation will soon result in chip temperatures exceeding their maximum limit, causing reduced performance or even failure. Many advanced cooling technologies have been developed to meet these needs, including small-scale micro-channels. These passages have dimensions smaller than one millimeter, greatly increasing the overall surface area and associated heat transfer. Unfortunately, even these aggressive methods may soon reach their conventional limits.
Recently, researchers have sought methods of enhancing the heat transfer for micro-channel heat sinks. However, because these cooling devices must then be attached to the electronics, there are numerous other layers in the package that increase the overall thermal resistance, meaning that any enhancement has an almost negligible benefit. Fortunately, new packaging designs have eliminated the need for many of these layers by placing the micro-channels intimately in contact with the electronics. In this integral structure, enhancements can indeed have a significant benefit, potentially increasing the cooling capacity by 25 to 30% and extending the performance levels for the electronics.
A team at Washington State University Vancouver is collaborating with researchers at General Electric Global Research to produce an enhanced integral micro-channel heat sink. The WSU team will analyze a two-dimensional form of a dimple enhancement, similar to the surface features on golf balls. These dimples act to augment the turbulence and mixing of the coolant, increasing the heat transfer with only a small increase in pumping requirement. The team will conduct computer simulations of the fluid flow past these surface grooves to help choose an optimal geometric configuration, and then they will manufacture an experimental version to test the benefits of the design at GE Global Research. The optimized solution can then be applied to numerous high-power electronics applications, including electric vehicles, MRIs, aircraft engines, and generators.