Summary In this work, an immersed boundary method, called the local domain‐free discretization (DFD) method, is extended to large eddy simulation (LES) of turbulent flows. The discrete form of partial differential equations at an interior node may involve some nodes outside the solution domain. The flow variables at these exterior dependent nodes are evaluated via linear extrapolation along the direction normal to the wall. To alleviate the requirement of mesh resolution in the near‐wall region, a wall model based on the turbulence boundary layer equations is introduced. The wall shear stress yielded by the wall model and the no‐penetration condition are enforced at the immersed boundary to evaluate the velocity components at an exterior dependent node. For turbulence closure, a dynamic subgrid scale (SGS) model is adopted and the Lagrangian averaging procedure is used to compute the model coefficient. The SGS eddy viscosity at an exterior dependent node is set to be equal to that at the outer layer. To maintain the mass conservation near the immersed boundary, a mass source/sink term is added into the continuity equation. Numerical experiments on relatively coarse meshes with stationary or moving solid boundaries have been conducted to verify the ability of the present LES‐DFD method. The predicted results agree well with the published experimental or numerical data.

Mean‐flow variables at the immersed boundary (IB) nodes (ie, interior near‐wall nodes) are evaluated via linear interpolation in the normal direction to close the discrete form of governing equations. To reduce the near‐wall mesh intervals, the tangential velocity at IB nodes is determined by enforcing the wall shear stress modified by the wall modeling technique. Analytical solutions in the near‐wall region are utilized to determine the turbulence variables of SST k‐ω or S‐A model at IB nodes.

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