CREARE LLC — Department of Defense STTR Phase II: N10A-T027

Description

The performance of modern combustion systems used in propulsion devices (such as gas turbine main combustors, augmentors, and rockets) is largely dependent on the mixing of fuel and oxidizer. This mixing process, often involving a liquid jet emanating into a gaseous flow followed by subsequent breakup and atomization, is critically important to many performance metrics including thrust, efficiency, static stability, dynamic stability, and emissions. Despite the importance of jet breakup and atomization, the process is poorly understood and design approaches are largely based on correlations, yielding mixed results. Our poor understanding of liquid jet dynamics is partly due to the fact that the diagnostic tools currently available to study liquid jet behavior have a limited ability to visualize the dense core region of the jet. Near field dynamics occurring close to the injector typically play a dominant role in determining the fuel distribution in the combustion zone. During our Phase I project, Creare and MIT applied an emerging 3-D imaging technique called Wave Front Imaging (WFI) to sprays for the first time. In Phase II, we will optimize WFI hardware and software into a powerful research tool, and demonstrate the new diagnostic under conditions relevant to aerospace propulsion.