the incompressible N-S equation was discretized with the second order upwind scheme to evaluate the convective term and the over-relaxed correction approach to calculating the diffusion term in unstructured grids systems. The pressure equation was derived by the modified momentum interpolation method
and the IDEAL algorithm was adopted in unstructured grids to treat the coupling of pressure and velocity. The formula for calculating static pressure of the internal nodes near boundary was derived by the Taylor expansion
and then the boundary pressure was employed in the iterative computation of the pressure equation to ensure the transfer of information from boundary to internal domain. The calculation formulae of the velocity at the pressure inlet and outlet were derived from the mass conservation law. The method proposed was evaluated by pressure-driven laminar internal flow
T-branch flow and buoyancy-driven flow
and then the solutions were compared with those in the literature. The results show that the present method is effective and feasible.
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Keywords
references
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