A Project to Assist Children in Classrooms to Successfully Communicate with Their Handicapped Peers (Project Child-to-Child)

Not Available The high performance, high power density combustors being proposed for IHPTET III must operate without exhinbintng combustion instability. There is a need to develop a time-accurate CFD combustion dynamics code that provides improved understanding of the acoustic/heat-release coupling and is able t predict the frequency and limit cycle of the instability. The code also needs to be practical enough to be used as a designtool to assess passive or active fixes in a timely manner. In Phase I of this SBIR, the feasibility of a Large Eddy Simulation (LES) code that captures heat release/acoustic coupling will be demonstrated. Having previously shown the feasibility of capturng gaseous-fueled combustion instability, this Phase I effort will focus on liquid-fueld combustion instability analysis. Prediction will be compared to Pratt & Whitney single nozzle experiments that utilize the high shear fuel injector. In order to acount for the temporal variation of fuel spray, the liquid spray boundary conditions will be changed (i.e. drop velocity, SMD, etc.) based on local (temporal) airflow conditions. Also, a reduced chemical model will be developed and incorporated to describe the heat release of JP fuels. In Phase II, the LES methodology willbeimproved by incorporating Linear Eddy based subgrid models for chemical reaction and vaperization,and further validated. The LES code will then be applied to IHPTET III combustor configurations fromPratt & Whitneyand General Electric.