A 3-D Nodal-Averaged Gradient Approach For Unstructured-Grid Cell-Centered Finite-Volume Methods For Application to Turbulent Hypersonic Flow

The flow over bluff bodies is separated compared to the flow over streamlined bodies. The investigation of the fluid flow over a cylinder with a streamwise slit has received little attention in the past, however there is some experimental evidence that show for turbulent regime it reduces the drag coefficient. This work helps in understanding the fluid flow over such cylinders in the laminar regime. As the width of the slit increases the drag coefficient keeps on reducing resulting in a narrower wake as compared to what is expected for flow over a cylinder. In this work we have used two different approaches in modelling a 2D flow for Re=10 to compare the results for CFD using finite volume method (ANSYS FLUENTTM) and Lattice Boltzmann methods. In all cases cylinders of circular cross section have been considered while slit width changing from 10% to 40% of the cylinder diameter. . It will be shown that drag coefficient decreases as the slit ratio increases. The effect of slit size on drag reduction is studied and discussed in detail in the paper. We have also made comparison of the results obtained from Lattice Boltzmann and finite volume methods.

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Hermite WENO limiting for multi-moment finite-volume methods using the ADER-DT time discretization for 1-D systems of conservation laws

Journal of Computational Physics ◽

10.1016/j.jcp.2014.11.017 ◽

2015 ◽

Vol 282 ◽

pp. 381-396 ◽

Cited By ~ 2

Author(s):

Matthew R. Norman

Keyword(s):

Conservation Laws ◽

Finite Volume ◽

Time Discretization ◽

Finite Volume Methods ◽

Systems Of Conservation Laws

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Extending the global-direction stencil with “face-area-weighted centroid” to unstructured finite volume discretization from integral form

Advances in Aerodynamics ◽

10.1186/s42774-020-00048-5 ◽

2020 ◽

Vol 2 (1) ◽

Author(s):

Lingfa Kong ◽

Yidao Dong ◽

Wei Liu ◽

Huaibao Zhang

Keyword(s):

Convergence Rate ◽

Finite Volume ◽

Differential Form ◽

Integral Form ◽

Finite Volume Methods ◽

Reconstruction Method ◽

Computational Accuracy ◽

Face Area ◽

Finite Volume Discretization ◽

Skewness Reduction

AbstractAccuracy of unstructured finite volume discretization is greatly influenced by the gradient reconstruction. For the commonly used k-exact reconstruction method, the cell centroid is always chosen as the reference point to formulate the reconstructed function. But in some practical problems, such as the boundary layer, cells in this area are always set with high aspect ratio to improve the local field resolution, and if geometric centroid is still utilized for the spatial discretization, the severe grid skewness cannot be avoided, which is adverse to the numerical performance of unstructured finite volume solver. In previous work [Kong, et al. Chin Phys B 29(10):100203, 2020], we explored a novel global-direction stencil and combined it with the face-area-weighted centroid on unstructured finite volume methods from differential form to realize the skewness reduction and a better reflection of flow anisotropy. Greatly inspired by the differential form, in this research, we demonstrate that it is also feasible to extend this novel method to the unstructured finite volume discretization from integral form on both second and third-order finite volume solver. Numerical examples governed by linear convective, Euler and Laplacian equations are utilized to examine the correctness as well as effectiveness of this extension. Compared with traditional vertex-neighbor and face-neighbor stencils based on the geometric centroid, the grid skewness is almost eliminated and computational accuracy as well as convergence rate is greatly improved by the global-direction stencil with face-area-weighted centroid. As a result, on unstructured finite volume discretization from integral form, the method also has superiorities on both computational accuracy and convergence rate.

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Inflow-implicit/outflow-explicit finite volume methods for solving advection equations

Applied Numerical Mathematics ◽

10.1016/j.apnum.2014.06.002 ◽

2014 ◽

Vol 85 ◽

pp. 16-37 ◽

Cited By ~ 7

Author(s):

Karol Mikula ◽

Mario Ohlberger ◽

Jozef Urbán

Keyword(s):

Finite Volume ◽

Finite Volume Methods

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