A Numerical model based on the mixed interface-tracking/interface-capturing technique (MITICT) for flows with fluid-solid and fluid-fluid interfaces

We propose a numerical model for computation of flow problems that involve both fluid-solid and fluid-fluid interfaces. The model is based on the mixed interface-tracking/interface-capturing technique (MITICT), which was introduced earlier for problems that involve both fluid-solid interfaces that are accurately tracked with a moving mesh method and fluid-fluid interfaces that are too complex to track and therefore treated with an interface-capturing technique. In our numerical model, fluid-solid interfaces are handled with the moving Lagrangian interface technique (MLIT) and fluid-fluid interfaces with the edge-tracked interface locator technique (ETILT). The mixed technique is tested in computation of a fluid-particle interaction problem in the presence of a fluid-fluid interface impacted by the particle.