Combustion instability and the design of a liquid droplet injector

A liquid droplet injector has been designed, built, and tested in order to create a monodispersed spray. This device will be used in future work outside the scope of this thesis to measure the combustion response of a hydrocarbon fuel. In order to create a stable injector, a thorough review of combustion instabilities is presented including a description of flow regimes and current droplet injector information to understand and begin the design process. After the design of the injector was completed, testing was conducted and photography was used to capture the images of the droplet streams. An analysis was performed on the droplet photos which revealed that the spray was not completely monodispersed. However, a section has been included that discusses both theoretical and analytical errors that contributed to the results. The injector needs more experimentation to achieve the goal of creating an optimal spray pattern.