Rough surfaces for heat dissipation

MIT researchers set out to better understand cooling that occurs across a liquid-gas phase changes. In particular, to maximize cooling, the group varied the roughness of a surface and found that increased roughness greatly improves heat transfer. Better heat transfer is needed in a wide variety of applications, especially in performance electronics, and the team's microscopically patterned surfaces could lead to greatly improved heat dissipation technologies. They etched a variety of precise cylindrical structures on the experimental surfaces, increasing the surface area. The team also formulated a model that explains the increased heat dissipation. An important reason for the increased heat dissipation is that the surface roughness prevents the formation of a vapor layer that would inhibit dissipation normally.