Instabilities in stratified mixing
layers Gelfgat & Kit, JFM, 2006,
vol. 552, pp. 189-227 |
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Temporal formulation
Perturbation: u’,v’,p’,T’ ~ exp(iax) Governing parameters:
Re, Ri, Pe, R=dv/dT Calculation of 2D case:
animation Calculation of 3D case:
animation1 animation2 Spatial formulation Spatial wavenumber of excitation: Spatial wavenumber of perturbation: Length scale: Governing parameters: Re, Ri,
Pe, l, , R=dv/dT Calculation of 2D case: animation Scales and governing parameters:
General form of perturbation: A(y)exp[i(ax+azz+wt)] Criterion for the temporal instability: a=a0, Im(w)<0 Criterion for the spatial instability: w=w0, Im(a)<0
or Im(b)<0 to solve for both temporal and spatial instabilities Profiles of temporal and spatial
perturbations for isothermal flow Dependencies of w
and b on the mixing layer thickness x Dependencies of w
and b on the Richardson number Ri
Dependencies of w
and b on the Reynolds number Re Stability
diagrams in x–Re planes Possibility for 3D
initial growth |