Project Description:

Purdue University has recently acquired the HyPulse reflected shock/expansion tunnel, which is a short-duration, free-jet wind tunnel in which the test gas is heated by adiabatic compression using shock waves, capable of producing flows at realistic temperatures up to Mach 25 and above. This is a uniquely versatile facility which, through the fabrication of relatively inexpensive nozzles contained within the facility’s test section, is more capable of varying Mach number and flow conditions than comparable high-enthalpy wind tunnels.

High-enthalpy flows pose numerous numerical challenges due to the very steep thermodynamic gradients at the wall (i.e. high-degree of wall cooling). A good trade-off between artificial dissipation, needed to stabilize the calculations, and accuracy is hard to achieve. Commonly used numerical scheme such as WENO guarantee robust results at the expense of loss of accuracy near the cut-off wavenumber and lack a mathematical foundation for compressible subgrid-scale turbulence modeling.

Recent breakthrough in compressible LES modeling in Scalo’s group allows the simulation of transitional and turbulent hypersonic flow, with and without shocks, with a common numerical approach. The current proposal aims to extend this approach to incorporate real gas effects and seek validation against experiments carried out by Prof. Jewell in HyPulse, as well as to extend and improve the performance envelope of the HyPulse facility via the design, transient simulation, and development of new nozzles for new hypervelocity flow conditions.

Start Date:

March -- June 2023

Postdoc Qualifications:

The ideal postdoc candidate needs to have extensive experience in high-performance computing and compressible turbulence modeling.
US Citizenship is preferred but not required.

Co-Advisors:

Carlo Scalo (scalo@purdue.edu)
Associate Professor
School of Mechanical Engineering
https://engineering.purdue.edu/~scalo/

Joe Jewell (jsjwell@purdue.edu)
Assistant Professor
School of Aeronautics and Astronautics
https://engineering.purdue.edu/AAE/people/ptProfile?resource_id=221718

Bibliography:

Jewell, Boundary-layer transition on a slender cone in hypervelocity flow with real gas effects, PhD Thesis, CalTech, 2014

Oddo, Hill, Reeder, Chin, Embrador, Komives, Tufts, Borg, Jewell, Effect of surface cooling on second-mode dominated hypersonic boundary layer transition, Experiments in Fluids, 2021, 62(7), 1-18.

Sousa and Scalo, A unified Quasi-Spectral Viscosity (QSV) approach to shock capturing and large-eddy simulation, J. Comput. Phys., 2022, Vol 459, 1111139

Sousa and Scalo, A Legendre spectral viscosity (LSV) method applied to shock capturing for high-order flux-reconstruction schemes, J. Comput. Phys., 2022, Vol 460, 111157.