A multiple instance solver framework based on dynamic overset grid method for flow field simulation of array configuration with moving components

Abstract

This paper presents a novel computational fluid dynamics (CFD) framework for flow simulation of complex configurations containing relatively moving components. The framework is based on the dynamic overset grid method and is intrinsically parallel. The user only needs to decompose complex configurations into topologically simple components according to the geometric features and generate high-quality computational meshes around these components. The framework can then automatically instantiate multiple fully functional CFD solvers to solve the flow fields on the meshes of all components simultaneously in a one-to-one correspondence. Thus, the geometric relationships of the components are transformed into concurrent states of the instance solvers, and accordingly, their flow fields are coupled through the intercommunication among instance solvers. The framework is implemented in a parallel environment based on the Message Passing Interface (MPI). An instantiation space is formed by splitting the world communicator into desired number of fully functional sub-communicators. Within this space, the same number of independent solvers with complete input and output interfaces can be instantiated from the same template solver. The data coupling between instance solvers is realised using the dynamic overset grid method, and the whole process is achieved automation by approaches of collision detection, Exact Inverse Maps (EIM)-based donor cell search, and robust Implicit Hole Cutting (IHC). Numerical results show that the framework is effective for configurations with complex topologies, and it is particularly suitable for numerical simulations of array configurations with relatively moving components.