The boundary slip error resulting from the interpolation/spreading non-reciprocity of direct-forcing immersed-boundary method is analyzed based on a simple and generic theoretical framework. In explicit implementations, scales with Courant number, as predicted by analysis confirmed lattice-Boltzmann simulation results. Using an analytical approximation error, force can be corrected in order to ...

In this manuscript we present a p-th degree immersed finite element method for solving boundary value problems with discontinuous coefficients. In this method, interface jump conditions are employed in the finite element basis functions, and the mesh does not have to be aligned with coefficient discontinuity. We show that under h refinement the immersed finite element solution converges to the ...

Accurate modeling of atmospheric flows over topography plays an important role in the prediction of local weather in mountain areas and snow avalanche due to wind-induced snow redistribution. Large eddy simulation (LES) is a numerical technique in which only the large eddies of the turbulent motions are calculated and the net effect of the small eddies is modeled by a subgrid scale (SGS) model,...

The Interpolated Bounce-Back (IBB) method and Immersed-Boundary (IB) method are compared for fluid-solid boundary conditions in the Lattice Boltzmann Equation (LBE) in terms of their numerical accuracy and computational efficiency. We carry out simulations for the flow past a circular cylinder asymmetrically placed in the channel in two dimensions with the Reynolds number Re = 20 and 100, corre...

Crickets are able to sense their surrounding environment through about 2000 filiform hairs located on a pair of abdominal cerci. The mechanism by which the cricket is able to sense a wide range of input signals using these filiform hairs of different length and orientation is of great interest. Most of the previous filiform hair models have focused on a single, rigid hair in an idealized air fi...

We describe a method for discretizing planar C2-regular domains immersed in nonconforming triangulations. The method consists in constructing mappings from triangles in a background mesh to curvilinear ones that conform exactly to the immersed domain. Constructing such a map relies on a novel way of parameterizing the immersed boundary over a collection of nearby edges with its closest point pr...

A global methodology for simulating multiphase flows and heat transfers interacting with complex objects or interfaces is presented. Elliptic equations or Navier-Stokes equations are resolved on a fixed structured curvilinear grid and the solid objects are initially represented by triangular surface elements. Several difficulties arise as soon as these two non-conforming grids have to interact ...

From the immersed boundary (IB) method point of view, the solid part may mainly act as elastic body or rigid body. Traditionally, the IB approach for fluid and rigid body interaction or fluid dynamics with complex geometry and boundary conditions has been divided into two main categories: the feedback forcing approach and the direct forcing approach. In the direct-forcing IB approach, the body ...

A volume-penalizing immersed boundary method is presented for the simulation of laminar incompressible flow inside geometrically complex blood vessels in the human brain. We concentrate on cerebral aneurysms and compute flow in curved brain vessels with and without spherical aneurysm cavities attached. We approximate blood as an incompressible Newtonian fluid and simulate the flow with the use ...

We present several coupled finite and boundary element formulations for the vibro-acoustic simulation of completely immersed bodies such as submarines. All formulations are based on the different use of standard boundary integral equations. In addition to the well known symmetric coupling we discuss two different approaches which are based on the weakly singular boundary integral equation only.