Mixing Generated by Rayleigh-taylor and Richtmyer-meshkov Instabilities
نویسنده
چکیده
We apply the Canuto-Goldman (CG) analytical model to turbulence generated by the class of instabilities which have a power-law growth rate. For the case of Rayleigh-Taylor (RT) instability we compare the results of the model with the experiments of Read and Youngs and find reasonable agreement on the scale size of large eddies: they are predicted to be a0% of the mixing length and are at least an order of magnitude larger than the smallest eddies. We interpret this as chunk mix. Based on the experiments of Read and Yotmgs we develop a simple model for turbulence generated by Richtmyer-Meshkov (RIM) instabilities. The CG method applied to our model predicts that the relative sizes of large eddies and small eddies do not vary by more than 60%. We interpret this as atomic mix. Independently of the CG model we find that the ratio of turbulent to directed energy is about 2~ and 9% for RT and RM respectively, and varies as the square of the Atwood number in both cases.
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