Large-Eddy Simulation of Turbulent Trans- and Supercritical Mixing

Abstract

In a joint effort towards the development of robust numerical tools for Large-Eddy Simulations (LES) of the injection, mixing and combustion process in the high-pressure environments of liquid-propellant rocket engines, a consistent model of real-gas thermophysical effects has been developed and implemented into two different CFD codes: INCA with a density-based approach and a pressure-based version of OpenFOAM. As part of the validation process, LES of trans-and supercritical nitrogen jets have been performed with different subgrid-scale modeling approaches. Despite the different code architecture and turbulence models, the numerical results are in excellent agreement with each other and with experimental reference data. Compared to experimental data, our results have the same or better quality as those from previous simulations.

Large Eddy Simulation of Supercritical Mixing and Combustion for Rocket Applications

“…Resting on the foundations of previous thermodynamic studies, 30 they defined simple mixing rules, derived a clear set of thermodynamically consistent fluid properties, investigated Dufour and Soret effects in supercritical flows, 12 addressed the handling of characteristic boundary conditions 18 and the sub-grid scale modeling 19 in the supercritical environment. Other groups have studied transcritical nitrogen injection using Reynolds-Average Navier-Stokes, 20,21 large eddy simulation 22,23 and direct numerical simulations. [24][25][26] A number of reacting high-pressure simulations have been attempted, most notably as part of the Rocket Combustion Modeling Workshop held in 2001 and 2006.…”

“…As it is one of the most well-established experiments, it has been used as a benchmark validation case by many groups. It has been investigated using Reynolds-averaged Navier-Stokes (RANS) equations, 20,21 large-eddy simulations 22,23,[42][43][44] and direct numerical simulation. 26 The setup consists of an injector (2.2 mm diameter) injecting nitrogen into a large pressurized vessel at 4.0 MPa at a constant velocity of 5.04 m/s.…”

“…Previous works have used artificial dissipation with user-defined coefficients 22,26 or with flux-limiters. 23 In the present work, a dual-threshold approach was used. The density-based sensor switches between a second-order ENO and first-order scheme to suppress the oscillations.…”

Large-Eddy Simulation of Coaxial LN2/GH2 Injection at Trans- and Supercritical Conditions

“…An example is the volume-translation method of Harstad et al 13 that was used for LES of supercritical single-species injection. 14,15,11 In the present work, we employ the recently proposed volume-translation method of Abudour et al 16 for binary mixtures. It is based on the PR EoS and relates the volume shift to the distance between the mixture's pressure-volume isotherm and its critical point.…”

The absence of a dense potential core in supercritical injection: A thermal break-up mechanism

“…These experiments have been simulated by numerous researchers (e.g., Kim et al, 15 Müller et al, 16 Niedermeier et al, 17 Schmitt et al, 18,19 Hickey et al, 20 Cutrone et al, 21,22 Cheng and Farmer, 23 Jarczyk and Pfitzner, 24 Terashima and Koshi, 25 and Antunes et al 26 ). Exemplarily, two sets of results are shown in Fig.…”