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Transient growth in Taylor-Couette flow

Hristina Hristova·Sebastien Roch·Peter J. Schmid·Laurette S. Tuckerman
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Abstract

Transient growth due to non-normality is investigated for the Taylor-Couette problem with counter-rotating cylinders as a function of aspect ratio eta and Reynolds number Re. For all Re < 500, transient growth is enhanced by curvature, i.e. is greater for eta < 1 than for eta = 1, the plane Couette limit. For fixed Re < 130 it is found that the greatest transient growth is achieved for eta between the Taylor-Couette linear stability boundary, if it exists, and one, while for Re > 130 the greatest transient growth is achieved for eta on the linear stability boundary. Transient growth is shown to be approximately 20% higher near the linear stability boundary at Re = 310, eta = 0.986 than at Re = 310, eta = 1, near the threshold observed for transition in plane Couette flow. The energy in the optimal inputs is primarily meridional; that in the optimal outputs is primarily azimuthal. Pseudospectra are calculated for two contrasting cases. For large curvature, eta = 0.5, the pseudospectra adhere more closely to the spectrum than in a narrow gap case, eta = 0.99.

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Hristina Hristova, Sebastien Roch, Peter J. Schmid, Laurette S. Tuckerman. 2002-10-02. Transient growth in Taylor-Couette flow. https://doi.org/10.1063/1.1502658

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