The objective of this project is to establish the basic engineering relationships required for the minimization of undesirable convective heat transfer in combustion systems through the application of electric fields. The program will provide verification of the feasibility of applying these relationships to practical devices, through an experimental program testing this concept over a variety of conditions. A range of combustion and electrical conditions will be evaluated in a step combustor, a basic research tool embodying physical features relevant to practical devices. Primary instrumentation will be an optical thermal imaging system and schlieren visualization system; experimental results will include flowfield visualization, thermal contour maps of the combustor wall, analyses of the local internal heat transfer coefficient under the range of flow conditions tested, and dependence of these parameters on applied electric field strength and electrode configuration. Application of the results of this program will provide reductions in undesired convective heat transfer coefficients to surfaces near combustion processes. This will allow higher operating temperatures and decrease wall cooling requirements, leading to associated higher efficiencies in combustion engines.
