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Numerical Modeling of High-Pressure Multi-phase Multi-species Flows

AMS Seminar Series

Speaker: Nguyen Ly, Stanford University

Presentation

Seminar Slide Deck (PDF-25.6MB)

Abstract

The injection of multi-species fluids into high-pressure and high-temperature environments beyond the species' critical points is commonly found in engineering applications. At these conditions, for immiscible species, both subcritical interfacial dynamics and supercritical mixing can coexist due to variations in temperature around the mixture critical point. The modeling of these complex transcritical phenomena for large-scale configurations is so far not possible.

In this talk, we present the recent development of the Regularized-Interface Method (RIM) as a unified formulation that can describe both sub- and supercritical processes as well as the transition between them. The proposed method is derived via filtering of the nanoscale interface resolving formulation based on van der Waals' linear gradient theory. Thus, this approach allows for the consistent modeling of interfacial dynamics that vanishes at supercritical conditions, while significantly reducing the temporal and spatial resolution constraints of the original nanoscale formulation. The resulting RIM formulation is examined in interface-capturing simulations of sub-, trans-, and supercritical fuel injection processes, involving droplets, jets, and mixing layers. These results highlight the importance of resolving spatio-temporal transitions from subcritical interfacial dynamics to supercritical mixing in high-pressure multiphase simulations.

Biography

Photo of Nguyen Ly
Nguyen Ly is a Ph.D. candidate at Stanford University in the department of Mechanical Engineering, working under the guidance of Professor Matthias Ihme. He is also a recipient of the NSTGRO fellowship. At Stanford, Nguyen’s research interest lies in the development of advanced numerical models and high-performance computing codes for simulating complex multiphase fluid dynamics, with application to automotive and space industries. Prior to joining Stanford in 2018, he earned his bachelor’s degree in aeronautical engineering from Rensselaer Polytechnic Institute, where he worked on bifurcation theory of swirling flows under the guidance of Professor Zvi Rusak.