Mar 11 2009
Department of Physics of the University of Milan shows that nanofluids can act as smart materials that can be switched on and off to dissipate heat efficiently or poorly. Heating and cooling are of cardinal importance to attain optimal performances in any technological device.
In the past, the attention of scientists and engineers has been mostly focused on the dissipation of great amounts of heat, the rationale behind that being that a high dissipation prevents overheating and thus enhances the efficiency of a device: the old good “the more powerful-the better!”.
In recent times, the lack of abundant sources of clean energy and the widespread dissemination of battery operated devices, such as cell-phones and laptops, have highlighted the need for a smart technological handling of energetic resources.
In a recent paper that will be published in the issue of March 13, 2009 of Physical Review Letters (http://prl.aps.org/) Gea Donzelli, Roberto Cerbino and Alberto Vailati show that a particular class of nanofluids can be used as a smart material working as a heat valve to control the flow of heat. The nanofluid can be easily configured either in a “low” state, where it conducts heat poorly, or in a “high” state, where the dissipation is more efficient.
The experimental work has been performed by Dr. Gea Donzelli, under the supervision of Prof. Alberto Vailati, and in collaboration with Dr. Roberto Cerbino.