A second moment closure model for MHD turbulence

Abstract A multiblock Favre-Averaged Navier-Stokes (FANS) method has been developed in conjunction with a chimera domain decomposition technique for investigation of flat surface, discrete-hole film cooling performance. The finite-analytic method solves the FANS equations in conjunction with a near-wall second-order Reynolds stress (second-moment) closure model and a two-layer k-ε model. Comparisons of flow fields and turbulence quantities with experimental data clearly demonstrate the capability of the near-wall second-moment closure model for accurate resolution of the complex flow interaction bewteen the coolant jet and the mainstream. The near-wall second-moment anisotropic model provides better agreement in adiabatic film effectiveness prediction than the two-layer k-ε model.

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Application of a second-moment closure model to simulate the turbulent dispersion from an elevated line source

Heat and Mass Transfer ◽

10.1007/s002310050279 ◽

1999 ◽

Vol 34 (5) ◽

pp. 429-436 ◽

Cited By ~ 3

Author(s):

Y. Wang ◽

S. Komori

Keyword(s):

Line Source ◽

Turbulent Dispersion ◽

Moment Closure ◽

Closure Model ◽

Second Moment ◽

Second Moment Closure

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Computation of Flow and Heat Transfer in Two-Pass Channels With 60 deg Ribs

Journal of Heat Transfer ◽

10.1115/1.1371931 ◽

2001 ◽

Vol 123 (3) ◽

pp. 563-575 ◽

Cited By ~ 37

Author(s):

Yong-Jun Jang ◽

Hamn-Ching Chen ◽

Je-Chin Han

Keyword(s):

Heat Transfer ◽

Experimental Data ◽

Moment Closure ◽

Closure Model ◽

Second Moment ◽

Flow And Heat Transfer ◽

Numerical Predictions ◽

Sharp Turn ◽

Second Moment Closure ◽

Near Wall

Numerical predictions of three-dimensional flow and heat transfer are presented for a two-pass square channel with and without 60 deg angled parallel ribs. Square sectioned ribs were employed along one side surface. The rib height-to-hydraulic diameter ratio e/Dh is 0.125 and the rib pitch-to-height ratio (P/e) is 10. The computation results were compared with the experimental data of Ekkad and Han [1] at a Reynolds number (Re) of 30,000. A multi-block numerical method was used with a chimera domain decomposition technique. The finite analytic method solved the Reynolds-Averaged Navier Stokes equation in conjunction with a near-wall second-order Reynolds stress (second-moment) closure model, and a two-layer k-ε isotropic eddy viscosity model. Comparing the second-moment and two-layer calculations with the experimental data clearly demonstrated that the angled rib turbulators and the 180 deg sharp turn of the channel produced strong non-isotropic turbulence and heat fluxes, which significantly affected the flow fields and heat transfer coefficients. The near-wall second-moment closure model provides an improved heat transfer prediction in comparison with the k-ε model.

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