Ni-based microvalves for flow modulation: Toward active combustion control

We report on the development of nickel-based micro diaphragms for fluid flow modulation in aerospace applications. We fabricated, assembled, and tested these nickel-based micro diaphragms in a prototype mesoscale fuel injector. A combination of deep reactive etching, silicon loss molding, electroplating, and conventional machining techniques were applied to form the mesoscale fuel injector and the nickel diaphragms. Modulation of fluid flow through the fuel injector was demonstrated with this nickel diaphragm functioning as a valve. The nickel diaphragms were characterized and the measured results were compared with finite element analysis results. The primary goal of this work is to demonstrate the concept of flow modulation using a nickel-based diaphragm, with future generations to be produced in silicon carbide, and the future application of such technologies in active combustion control to mitigate combustion instabilities when they occur.