Each fuel injector has an air swirler to provide rapid mixing and a small recirculation zone for burning.
Rapid and uniform mixing, and small-burning zones, with short residence times, results in low-NOx
and particulate formation. An integrated-module approach is used for construction, utilizing Silicon Carbide
microelectromechanical systems (MEMS) fabrication technology that includes deep reactive ion etching.
The fabrication will combine multiple fuel injectors, fuel manifolds, fuel thermal protection and
air swirlers into a single module. One task will be to determine how fuel staging within a module can be
best accomplished. In the second task micro fuel valves will be integrated into the module to provide on/off
operation and provide active combustion control of individual fuel injectors. Electromagnetic control of
individual fuel injectors will improve uniformity, provide instability suppression and extend the operating range
to leaner burning mixtures to reduce NOx. The concept will be demonstrated in flame-tube tests to achieve greater
than an 80% NOx reduction goal, and reduce particulate and aerosol emissions. The MEMS fabrication technology
also has the potential to reduce the cost of manufacturing.
Robert R Tacina