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arXiv · 2609.06457

Unification of The Navier-Stokes Equation for Fluid Mechanics and Aeroacoustics

Tapan K. Sengupta
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Abstract

The Navier-Stokes equation for a compressible Newtonian fluid is reassessed, in view of recent investigation results on the foundations of aeroacoustics. In the process, the role and necessity of the so-called Stokes' hypothesis is reconsidered, which in its current practice omits the bulk viscosity. In contrast, the relevance of a new generalized kinematic viscosity is proposed, along with a new methodology that will enable estimation of second coefficient of viscosity completely obviating the necessity of making the Stokes' hypothesis. This opens up the vista of a new formulation for the Navier-Stokes equation applicable for both the subjects of fluid mechanics and aeroacoustics in a unified approach.

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Tapan K. Sengupta. 2026-09-06. Unification of The Navier-Stokes Equation for Fluid Mechanics and Aeroacoustics. https://arxiv.org/abs/2609.06457

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