1 research outputs found
A Novel Sharp Interface Immersed Boundary Framework for Viscous Flow Simulations at Arbitrary Mach Number Involving Complex and Moving Boundaries
This work presents a robust and efficient sharp interface immersed boundary
(IBM) framework, which is applicable for all-speed flow regimes and is capable
of handling arbitrarily complex bodies (stationary or moving). The work deploys
an in-house, parallel, multi-block structured finite volume flow solver, which
employs a 3D unsteady Favre averaged Navier Stokes equations in a generalized
curvilinear coordinate system; while we employ a combination of HCIB (Hybrid
Cartesian Immersed boundary) method and GC(Ghost-cell) for solution
reconstruction near immersed boundary interface. A significant difficulty for
these sharp interface approaches is of handling sharp features/edges of complex
geometries. In this study, we observe that apart from the need for robust node
classification strategy and higher order boundary formulations, the direction
in which the reconstruction procedures are performed plays an important role in
handling sharp edges. Taking this into account we present a versatile interface
tracking procedure based on ray tracing algorithm and a novel three step
solution reconstruction procedure that computes pseudo-normals in the regions
where the normal is not well-defined and reconstructs the flow field along
those directions. We demonstrate that this procedure enables solver to
efficiently handle and accurately represent sharp-edged regions. A fifth-order
weighted essentially non-oscillatory (WENO) scheme is used for capturing
shock-induced discontinuities and complex fluid-solid interactions with high
resolution. The developed IBM framework is applied to a wide range of flow
phenomena encompassing all-speed regimes (M=0.001 to M = 2.0). A total of seven
benchmark cases (three stationary and four moving bodies) are presented
involving various geometries (cylinder, airfoil, wedge) and the predictions are
found to be in excellent agreement with the published results