Title of Project: Realistic Simulation of Jet Engine Noise Using Petaflop Computing
Project PIs: G. Blaisdell (PI), A. Lyrintzis (co-PI), Z. Li (co-PI)
Project goals and description of work:
The goal of this project is to advance the science of subsonic and supersonic jet noise prediction for modern-day turbofan aircraft engines using petascale computing. The PIs will investigate turbulent mixing by accurately simulating it with advanced computational techniques based on large eddy simulation (LES). Integral acoustic methods will extend the computational fluid dynamics (CFD) results to the far-field. Previous experiments have shown that a 50% decrease in jet noise power output can be achieved by certain chevron and lobe mixer designs without essentially changing the net thrust of the engine. However, the physical mechanisms for the reduced noise are not well understood. Processing speeds and memory sizes of existing supercomputers limit current simulations to low Reynolds numbers and idealized geometries for the mixing devices. Thus, these simulations do not allow design and optimization of mixing for noise reduction, especially since these mixing devices influence the high frequencies of the noise spectrum, increasing the grid resolution requirements. Modeling at realistic Reynolds numbers and nozzle geometries requires tens of billions of points. Simply running existing codes on bigger computers is not the answer. The PIs algorithms will be designed to take advantage of multi-level parallelism and address the 'memory wall' aspect of multicore architectures where the cost of arithmetic operations is much smaller than memory references.