This proposal introduces an innovative fuel atomization device, the "smart nozzle", for gas turbine combustors. It consists of a conventional fuel atomizer and an innovated piezoelectric driver. It generates the spray through the fuel atomizer and modulates the spray structure through the piezoelectric driver. By adopting a conventional atomizer, the "smart nozzle" retains the basic characteristics of the current fuel atomization system but adds the controllability to spray structure. One will be able to adjust and optimize combustor performance by control of the fuel spray through the "smart nozzle". An analytical model describing the spray cone angle and nozzle discharge coefficient will be developed. The model will be verified with experimental data. Open loop response of the smart nozzle to control signal, such as the variation of cone angle under different driving conditions, will be measured. Laser Induced Fluorescence (LIF) will be used to measure spray patternation. As a result of the proposed work, a database about the smart nozzle operation will be compiled and used for flow tests and combustor performance verification in Phase-II. The acquired knowledge will lead to proper control of spray structure for satisfactory combustor performance. Smart nozzle enables on-line control of fuel spray and combustor performance in a wide range of operating conditions. Concurrent improvement in efficiency, and emissions reduction can be achieved as a result of improved combustor performance. Such a device can have a great market in gas turbine industry as well as other liquid spray related industries.
Keywords: Phase_I, NASA, Abstract, FY94
