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تسجيل مستخدم جديدRam pressure stripping of the hot gaseous haloes of galaxies using the k-epsilon sub-grid turbulence model
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We perform three dimensional hydrodynamic simulations of the ram pressure stripping of the hot extended gaseous halo of a massive galaxy using the k-epsilon sub-grid turbulence model at Mach numbers 0.9, 1.1 and 1.9. The k-epsilon model is used to simulate high Reynolds number flows by increasing the transport coefficients in regions of high turbulence. We find that the initial, instantaneous stripping is the same whether or not the k-epsilon model is implemented and is in agreement with the results of other studies. However the use of the k-epsilon model leads to five times less gas remaining after stripping by a supersonic flow has proceeded for 10 Gyr, which is more consistent with what simple analytic calculations indicate. Hence the continual Kelvin-Helmholtz stripping plays a significant role in the ram pressure stripping of the haloes of massive galaxies. To properly account for this, simulations of galaxy clusters will require the use of sub-grid turbulence models
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