Three-dimensional reacting shock-bubble interaction
Diegelmann, F., Hickel, S., Adams, N.A. (2017)
Combustion and Flame 181: 1339-1351. doi: 10.1016/j.combustflame.2017.03.026
We investigate a reacting shock–bubble interaction through three-dimensional numerical simulations with detailed chemistry. The convex shape of the bubble focuses the shock and generates regions of high pressure and temperature, which are sufficient to ignite the diluted stoichiometric H2-O2 gas mixture inside the bubble. We study the interaction between hydrodynamic instabilities and shock-induced reaction waves at a shock Mach number of Ma = 2.83.
Shock Mach number influence on reaction wave types and mixing in reactive shock-bubble interaction
Diegelmann, F., Hickel, S., Adams, N.A. (2016)
Combustion and Flame 174: 85-99. doi: 10.1016/j.combustflame.2016.09.014
We present numerical simulations for a reactive shock–bubble interaction with detailed chemistry. The convex shape of the bubble leads to shock focusing, which generates spots of high pressure and temperature. Pressure and temperature levels are sufficient to ignite the stoichiometric H2–O2 gas mixture. Shock Mach numbers between Ma = 2.13 and Ma = 2.90 induce different reaction wave types (deflagration and detonation).
On the pressure dependence of ignition and mixing in two-dimensional reactive shock-bubble interaction
Diegelmann, F., Tritschler, V., Hickel, S., Adams, N.A. (2016)
Combustion and Flame 163:414-426. doi: 10.1016/j.combustflame.2015.10.016
We analyse results of numerical simulations of reactive shock-bubble interaction with detailed chemistry. The interaction of the Richtmyer–Meshkov instability and shock-induced ignition of a stoichiometric H2-O2 gas mixture is investigated. Different types of ignition (deflagration and detonation) are observed at the same shock Mach number of Ma = 2.30 upon varying initial pressure.
Evolution of length scales and statistics of Richtmyer-Meshkov instability from direct numerical simulations
Tritschler, V.K., Zubel, M., Hickel, S., Adams, N.A. (2014)
Physical Review E 90: 063001. doi: 10.1103/PhysRevE.90.063001
In this study we present direct numerical simulation results of the Richtmyer-Meshkov instability (RMI) initiated by Ma = 1.05, Ma = 1.2, and Ma = 1.5 shock waves interacting with a perturbed planar interface between air and SF6. At the lowest shock Mach number the fluids slowly mix due to viscous diffusion, whereas at the highest shock Mach number the mixing zone becomes turbulent.
On the Richtmyer-Meshkov instability evolving from a deterministic multimode planar interface
Tritschler, V., Olson, B., Lele, S., Hickel, S., Hu, X.Y., Adams, N.A. (2014)
Journal of Fluid Mechanics 755, 429-462. doi: 10.1017/jfm.2014.436
We investigate the shock-induced turbulent mixing between a light and a heavy gas, where a Richtmyer–Meshkov instability (RMI) is initiated by a shock wave with Mach number Ma = 1.5. The prescribed initial conditions define a deterministic multimode interface perturbation between the gases, which can be imposed exactly for different simulation codes and resolutions to allow for quantitative comparison. Well-resolved large-eddy simulations are performed using two different and independently developed numerical methods with the objective of assessing turbulence structures, prediction uncertainties and convergence behaviour.
Quantification of initial-data uncertainty on a shock-accelerated gas cylinder
Tritschler, V.K., Avdonin, A., Hickel, S., Hu, X.Y., Adams, N.A. (2014)
Physics of Fluids 26: 026101. doi: 10.1063/1.4865756
We quantify initial-data uncertainties on a shock accelerated heavy-gas cylinder by two-dimensional well-resolved direct numerical simulations. A high-resolution compressible multicomponent flow simulation model is coupled with a polynomial chaos expansion to propagate the initial-data uncertainties to the output quantities of interest.
On the Kolmogorov inertial subrange developing from Richtmyer-Meshkov instability
Tritschler, V.K., Hickel, S., Hu, X.Y., Adams, N.A. (2013)
Physics of Fluids 25: 071701. doi: 10.1063/1.4813608
We present results of well-resolved direct numerical simulations (DNS) of the turbulent flowevolving from Richtmyer-Meshkov instability (RMI) in a shock-tube with square cross section. The RMI occurs at the interface between a mixture of O2 and N2 (light gas) and SF6 and acetone (heavy gas).
Numerical simulation of a Richtmyer-Meshkov instability with an adaptive central-upwind 6th-order WENO scheme
Tritschler, V.K., Hu, X.Y., Hickel, S., Adams, N.A. (2013)
Physica Scripta 2013: 014016. doi: 10.1088/0031-8949/2013/T155/014016
Two-dimensional simulations of the single-mode Richtmyer–Meshkov instability (RMI) are conducted and compared to experimental results of Jacobs and Krivets (2005).