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A nonperturbative approximation for the moderate Reynolds number Navier-Stokes equations.

ABSTRACT: The nonlinearity of the Navier-Stokes equations makes predicting the flow of fluid around rapidly moving small bodies highly resistant to all approaches save careful experiments or brute force computation. Here, we show how a linearization of the Navier-Stokes equations captures the drag-determining features of the flow and allows simplified or analytical computation of the drag on bodies up to Reynolds number of order 100. We illustrate the utility of this linearization in 2 practical problems that normally can only be tackled with sophisticated numerical methods: understanding flow separation in the flow around a bluff body and finding drag-minimizing shapes.

SUBMITTER: Roper M

PROVIDER: S-EPMC2651293 | biostudies-literature | 2009 Mar

REPOSITORIES: biostudies-literature

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A nonperturbative approximation for the moderate Reynolds number Navier-Stokes equations.

Roper Marcus M Brenner Michael P MP

Proceedings of the National Academy of Sciences of the United States of America 20090211 9

The nonlinearity of the Navier-Stokes equations makes predicting the flow of fluid around rapidly moving small bodies highly resistant to all approaches save careful experiments or brute force computation. Here, we show how a linearization of the Navier-Stokes equations captures the drag-determining features of the flow and allows simplified or analytical computation of the drag on bodies up to Reynolds number of order 100. We illustrate the utility of this linearization in 2 practical problems ...[more]

PMID: 19211800

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