Better surfaces could help dissipate heat

Heat transfer in everything from computer chips to powerplants could be improved through new analysis of surface textures. Cooling systems that use a liquid that changes phase - such as water boiling on a surface - can play an important part in many developing technologies, including advanced microchips and concentrated solar-power systems. But understanding exactly how such systems work, and what kinds of surfaces maximize the transfer of heat, has remained a challenging problem. Now, researchers at MIT have found that relatively simple, microscale roughening of a surface can dramatically enhance its transfer of heat. Such an approach could be far less complex and more durable than approaches that enhance heat transfer through smaller patterning in the nanometer (billionths of a meter) range. The new research also provides a theoretical framework for analyzing the behavior of such systems, pointing the way to even greater improvements. The work was published this month in the journal Applied Physics Letters , in a paper co-authored by graduate student Kuang-Han Chu, postdoc Ryan Enright and Evelyn Wang, an associate professor of mechanical engineering.