Ionic winds for locally enhanced cooling

David Go, School of Mechanical Engineering and Birck Nanotechnology Center, Purdue University
Suresh Garimella, School of Mechanical Engineering and Birck Nanotechnology Center, Purdue University
Timothy Fisher, Mechanical Engineering and Birck Nanotechnology Center, Purdue University
Rajiv K. Mongia, Intel

Abstract

Ionic wind engines can be integrated onto surfaces to provide enhanced local cooling. Air ions generated by field-emitted electrons or a corona discharge are pulled by an electric field and exchange momentum with neutral air molecules, causing air flow. In the presence of a bulk flow, ionic winds distort the boundary layer, increasing heat transfer from the wall. Experiments demonstrate the ability of ionic winds to decrease the wall temperature substantially in the presence of a bulk flow over a flat plate, corresponding to local enhancement of the heat transfer coefficient by more than twofold. Multiphysics simulations of the corona and flow describe the ability of the ionic wind to distort a bulk flow boundary layer and confirm the experimentally observed heat transfer enhancement trends.