|
Abstract:
|
Electronics cooling was a field dominated by bulky and heavy heat sinks , heat pipes and fans for decades . Lately , the size of the electronic components has decreased to a substantial extent with an increase in performance . This has fuelled a need for smaller , lighter , yet efficient cooling systems . A lot of research has been done to build innovative cooling solutions which satisfied most of the requirements as stated above . Some of them still have limitations like use of the right coolants and design challenges . Digital microfluidics is one field which can solve all these issues by providing a simple , reliable and efficient way of pumping coolants over hotspots . For this purpose , a microfluidic hotspot cooling device was fabricated which used special liquids called Ionic Liquids (IL's ) as coolants . Unlike other coolants used , IL's has the property of being thermally stable at elevated temperatures and chemically inert to most of the known metals . This thesis report describes the performance of IL's in the device for hotspot cooling . Liquid Crystal Thermographical analysis was performed in order to estimate the temperatures of the hotspot and heat removal rate calculations were performed based on the analysis . In order to check the quality of the results , a comparison was made with the results of DI water . It was observed that DI water emerged as the best liquid for hotspot cooling and IL's performed poorly . This was due to the high heat capacities and thermal conductivities of water . In order to get better results for IL's , it was concluded that the thermal conductivity values should emulate that of water's values . Adding CNT's (Carbon Nanotubes ) to the IL can help us in this regard . Moreover , as the heat removal rate was a rough calculation , it was hard to estimate an accurate rate for the DI water and IL . Efforts are being made to come up with a realistic approach towards estimation of this data .In future , by increasing the thermal conductivities of IL's and using advanced methods to perform the analysis with an improvement in design of the hotspot cooling device , cooling hotspots in small , compact and powerful electronic devices can become a reality . |