An Efficient Immersed Boundary Algorithm for Simulation of Flows in Curved and Moving Geometries Manish Kumar, Somnath Roy, and Mohd. Sujaat Ali, Published in Computers & Fluids, 129, 159-178

Immersed Boundary Method can be a very effective tool for flow prediction over complex and moving geometries. However, its applicability is often restricted due to the computational overheads associated with the dynamic identification of immersed nodes and the high ratio of solid to fluid nodes. Earlier attempts to overcome these issues were usually mathematically involved and computationally expensive. In the present paper, a simple and robust IBM implementation has been demonstrated which addresses these issues. The present method preserves the simplicity of sharp interface immersed boundary method and hence avoids complex coding logistics. This method uses a dynamic search algorithm for tagging of the immersed nodes and reduces the computational overheads. Mass conservation is ensured in the intercepted cells through a hybrid SOLA-MAC algorithm. An overall second order accuracy is maintained in the discretization and interpolation schemes. The effectiveness and accuracy of the present scheme in handling the mass loss and spurious pressure fluctuation are demonstrated through a number of test cases. Comparisons are made with available experimental and numerical data for different external and internal flow problems.

The figure added shows variation of pressure coefficient over an oscillating cylinder predicted using this method and compared with available experimental data.

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Comparison of Time history of the pressure drag coefficient at Re = 100 and KC= 5 with result of Dütsch et al. (1998)