Transient growth calculations obtained directly from the Orr-Sommerfeld matrices

Lennon O'Naraigh

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arXiv · 1504.07064

Transient growth calculations obtained directly from the Orr-Sommerfeld matrices

Lennon O'Naraigh

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Abstract

We introduce and validate an algorithm to compute transient amplication factors for the Orr-Sommerfeld-Squire linear theory for parallel two-phase flow. We further introduce direct numerical simulation as a way of comparing the linear theory with early-stage wave growth in simulations. The simulation results are drawn from a strongly supercritical parameter case wherein the modal growth rates are strong. In this case, the modal growth dominates the transient growth

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Lennon O'Naraigh. 2015-04-27. Transient growth calculations obtained directly from the Orr-Sommerfeld matrices. https://arxiv.org/abs/1504.07064

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