Turbulent mixing induced by Richtmyer-Meshkov instability

Krivets, V. V.; Ferguson, Kevin; Jacobs, J. W.

doi:10.1063/1.4971732

Cited by 14 publications

(25 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…2014; Krivets et al. 2017) indicates membrane remnants suppress the growth exponent in the light–heavy configuration on average by . This is similar to an average growth reduction of found in the nonlinear interfacial harmonics by Mariani et al.…”

Section: Resultssupporting

confidence: 66%

See 1 more Smart Citation

The effect of initial conditions on mixing transition of the Richtmyer–Meshkov instability

et al. 2020

View full text Add to dashboard Cite

show abstract

Section: Resultssupporting

confidence: 66%

“…(2014) (), both of which used membraneless techniques to impose the initial conditions. Values by Krivets, Ferguson & Jacobs (2017) varied over a large range (0.19–0.57) having ensemble averages of and for bubble and spike growth exponents, respectively. Laser-driven experiments by Dimonte & Schneider (1997) found for .…”

Section: Resultsmentioning

confidence: 99%

The effect of initial conditions on mixing transition of the Richtmyer–Meshkov instability

et al. 2020

View full text Add to dashboard Cite

show abstract

“…7 gives a comparison of the final images from Experiment 4 with an image taken from a section of the m = −2 simulation at a bandwidth of R = 64, highlighting the very similar phenomenology. The majority of values reported for θ in [24] are also higher than the range of values typically reported for narrowband, short wavelength perturbations, suggesting that the growth rate of the layer is being influenced by linear growth of longer wavelengths. For example, in Experiment 4 the bubble and spike growth rates were θ b = 0.42 and θ s = 0.51 respectively, which suggests the perturbations used were broadband in nature.…”

Section: Resultsmentioning

confidence: 69%

“…5 also resemble quite closely the experimental (c) m = −3. images reported in Krivets et al [24]. Those image sequences, particularly for Experiment 4, show a transitional mixing layer containing a broad range of modes, the smallest of which have become turbulent by the end of the experiment, while the largest modes are still mostly linear.…”

Section: Resultsmentioning

confidence: 87%

The influence of initial perturbation power spectra on the growth of a turbulent mixing layer induced by Richtmyer–Meshkov instability

Groom

Thornber

2020

Physica D: Nonlinear Phenomena

View full text Add to dashboard Cite

This paper investigates the influence of different broadband perturbations on the evolution of a Richtmyer-Meshkov turbulent mixing layer initiated by a Mach 1.84 shock traversing a perturbed interface separating gases with a density ratio of 3:1. Both the bandwidth of modes in the interface perturbation, as well as their relative amplitudes, are varied in a series of carefully designed numerical simulations at grid resolutions up to 3.2×10 9 cells. Three different perturbations are considered, characterised by a power spectrum of the form P (k) ∝ k m where m = −1, −2 and −3. The growth of the mixing layer is shown to strongly depend on the initial conditions, with the growth rate exponent θ found to be 0.5, 0.63 and 0.75 for each value of m at the highest grid resolution. The asymptotic values of the molecular mixing fraction Θ are also shown to vary significantly with m; at the latest time considered Θ is 0.56, 0.39 and 0.20 respectively. Turbulent kinetic energy (TKE) is also analysed in both the temporal and spectral domains. The temporal decay rate of TKE is found not to match the predicted value of n = 2 − 3θ, which is shown to be due to a time-varying normalised dissipation rate C . In spectral space, the data follow the theoretical scaling of k (m+2)/2 at low wavenumbers and tend towards k −3/2 and k −5/3 scalings at high wavenumbers for the spectra of transverse and normal velocity components respectively. The results represent a significant extension of previous work on the Richtmyer-Meshkov instability evolving from broadband initial perturbations and provide useful benchmarks for future research.

show abstract

“…The narrowband case is a somewhat idealized test case which gives the smallest value of  . Many shock-driven experiments [48,49,50] have given higher values up to  ~ 0.6 which are likely to be the result of broadband initial conditions (reference [48] notes that the high value of  ~ 0.6 may be an overestimate due to late-time expansion of the laser target). A similar type of analysis is needed for broadband perturbations.…”

Section: The Asymptotic Value Of mentioning

confidence: 99%

Early Time Modifications to the Buoyancy-Drag Model for Richtmyer–Meshkov Mixing

Youngs

Thornber

2020

Journal of Fluids Engineering

View full text Add to dashboard Cite

The Buoyancy-Drag model is a simple model, based on ordinary differential equations, for estimating the growth in the width of a turbulent mixing zone at an interface between fluids of different density due to Richtmyer-Meshkov and Rayleigh-Taylor instabilities. The model is calibrated to give the required self-similar behaviour for mixing in simple situations. However, the early stages of the mixing process are very dependent on the initial conditions and modifications to the Buoyancy-Drag model are then needed to obtain correct results. In a recent paper, Thornber et al. [Phys. Fluids. 29 (2017) 105107], a range of three-dimensional simulation techniques were used to calculate the evolution of the mixing zone integral width due to single-shock Richtmyer-Meshkov mixing from narrowband initial random perturbations. Further analysis of the results of these simulations gives greater insight into the transition from the initial linear behaviour to late-time self-similar mixing and provides a way of modifying the Buoyancy-Drag model to treat the initial conditions accurately. Higher resolution simulations are used to calculate the early time behavior more accurately and compare with a multi-mode model based on the impulsive linear theory. The analysis of the iLES data also gives a new method for estimating the growth exponent , theta (mixing zone width ~ t^theta), which is suitable for simulations which do not fully reach the self-state. The estimates of theta are consistent with the theoretical model of Elbaz & Shvarts [Physics of Plasmas (2018), 25, 062126].

show abstract

Turbulent mixing induced by Richtmyer-Meshkov instability

Cited by 14 publications

References 5 publications

The effect of initial conditions on mixing transition of the Richtmyer–Meshkov instability

The effect of initial conditions on mixing transition of the Richtmyer–Meshkov instability

The influence of initial perturbation power spectra on the growth of a turbulent mixing layer induced by Richtmyer–Meshkov instability

Early Time Modifications to the Buoyancy-Drag Model for Richtmyer–Meshkov Mixing

Contact Info

Product

Resources

About