A new ultra-high-pressure optical chamber has been developed to ?facilitate direct observation of combustion experiments up to 300 MPa. ?This chamber features a relatively large 12?liter volume for ?near-constant-pressure burning conditions. Experiments using this ?chamber are reported for the combustion of liquid nitromethane burning ?from ~3 – 100 MPa which reveal three regimes of burning behavior, with ?each regime having a different dependency of burning rate on pressure. ?The change in burning behavior appears to be a result of passage from ?subcritical to supercritical combustion producing hydrodynamic ?instability from loss of surface tension, then transition to cellular ?and turbulent combustion. Modeling results are presented investigating ?ideal and real gas behavior over the experimental pressure range.

Bio:

RICHARD A. YETTER is Professor of Mechanical Engineering at the ?Pennsylvania State University. He received his PhD from Princeton ?University. His research interests are in power and propulsion systems ?with particular emphasis on high-pressure combustion, heterogeneous ?combustion, and energetic materials. He was previously a Research ?Engineer at the Scientific Research Laboratories of Ford Motor ?Company, a Senior Research Scientist and Lecturer at Princeton ?University, and a Research Collaborator at the Brookhaven National ?Laboratory. He is editor of Combustion Science and Technology, ?associate editor of Energetic Materials and Chemical Propulsion, and ?currently serves on the editorial board of Progress in Energy and ?Combustion Science and Journal of Propulsion and Power. He is a fellow ?of the Combustion Institute and ASME and a member of the AIAA, SAE, ?MRS, and ACS. Dr Yetter is an author of over two hundred scientific ?publications, two books, and two US patents. He is the recipient of ?the Silver Medal from the Combustion Institute and the Propellants and ?Combustion Award from the AIAA.