Direct numerical simulation of pipe flow using a solenoidal spectral method

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2012

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Tuğluk, Ozan

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In this study, which is numerical in nature, direct numerical simulation (DNS) of the pipe ow is performed. For the DNS a solenoidal spectral method is employed, this involves the expansion of the velocity using divergence free functions which also satisfy the prescribed boundary conditions, and a subsequent projection of the N-S equations onto the corresponding dual space. The solenoidal functions are formulated in Legendre polynomial space, which results in more favorable forms for the inner product integrals arising from the Petrov-Galerkin scheme employed. The developed numerical scheme is also used to investigate the e ects of spanwise oscillations and phase randomization on turbulence statistics, and drag, in turbulent incompressible pipe ow for low to moderate Reynolds numbers (i.e. Re 5000) ).

Subject Keywords

Numerical simulation., Spectral theory (Mathematics)., Fluid dynamics.

URI

http://etd.lib.metu.edu.tr/upload/12614293/index.pdf
https://hdl.handle.net/11511/21504

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

O. Tuğluk, “Direct numerical simulation of pipe flow using a solenoidal spectral method,” Ph.D. - Doctoral Program, Middle East Technical University, 2012.