Coupled Modal-Nonmodal Interactions Due to Periodic, Infinite Train of Convecting Vortices (TCV)

Jyothi Kumar Puttam; Prasannabalaji Sundaram; Vajjala K. Suman; Ankan Sarkar; Tapan K. Sengupta; Tirupathur N. Venkatesh; Rakesh K. Mathpal

arXiv · 2601.00295

Coupled Modal-Nonmodal Interactions Due to Periodic, Infinite Train of Convecting Vortices (TCV)

Jyothi Kumar Puttam·Prasannabalaji Sundaram·Vajjala K. Suman·Ankan Sarkar·Tapan K. Sengupta·Tirupathur N. Venkatesh·Rakesh K. Mathpal

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Abstract

Events during transition to turbulence either follow modal or non-modal routes, or combinations of the two. Here, we report a computational investigation of strong freestream excitation caused by a train of convecting vortices. For this TCV excitation, we show a strong interaction of modal and non-modal components causing a spectacular growth of disturbances. We propose this as the mechanism for the severe encounters due to convective vortical disturbances on the underlying shear layer.

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Jyothi Kumar Puttam, Prasannabalaji Sundaram, Vajjala K. Suman, Ankan Sarkar, Tapan K. Sengupta, Tirupathur N. Venkatesh, Rakesh K. Mathpal. 2026-01-01. Coupled Modal-Nonmodal Interactions Due to Periodic, Infinite Train of Convecting Vortices (TCV). https://arxiv.org/abs/2601.00295

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