Figure 1: LES domain with one jet
Figure 2: Vorticity magnitude isosurfaces colored with source strength. The planes show acoustic radiation using dilatation.
Prof. Santosh Hemchandra’s lab at Department of Aerospace Engineering performs Large Eddy Simulation (LES) of aerospace vehicles on Cray SahasraT. Most aerospace vehicles such as rockets and aircraft feature high momentum and temperature jets exiting the vehicle. These jets produce high levels of acoustic radiation over significantly a wide frequency range that can adversely impact the structural integrity of structures around launchpads and runways, as well as, detrimentally impact the health of personnel working routinely around these vehicles. The present study aims to understand the spectral characteristics of acoustic radiation in the far-field of twin round jets at an exit Mach number of 0.9 by varying the inter-jet spacing.
In 2019, Computations were performed using 12,000 cores per run on the SaharsaT Cray XC40 CPU system. The mesh size is about 96 million points.
“Our solver uses a domain decomposition strategy to solve the Navier-Stokes equations using the finite difference method. The cases run for this project cannot be run on our lab cluster. However, on cases that can be run on both CRAY and lab cluster, we see a 1.5x speedup on the cray relative to the lab cluster”, says Prof. Hemchandra.
Muthichur, N., Harikrishna, T., Hemchandra, S. and Samanta, A., “Sources of Sound and its Radiation from Twin Turbulent Jets”, AIAA aerospace science and technology forum, 2020, AIAA paper# 2020-1245.