Backward facing step: from fluid flow to conjugate heat transfer with the coupling library preCICE

The Backward Facing Step geometry is a widely used benchmark problem in Computational Fluid Dynamics literature that is exploitable to validate models, solution methods, and software implementations. Despite a simple geometry, it shows phenomena like separation, reattachment, and re-circulation zones, under different flow conditions (i.e. different Reynolds number or turbulence parameters) it gives different measurable results, suitable for benchmarking activities [1]. Also regarding heat transfer analysis, the backward facing step can be used to investigate a wide variety of operating conditions (both for simple heat transfer cases and coupling heat transfer between the fluid region and a neighboring solid region giving rise to a more complex conjugate heat transfer model) [2]. This work uses the backward facing step as a test case to validate a numerical model built with the open-source Software OpenFOAM 10. The fluid and solid subdomains are connected through the open-source coupling library preCICE [3]. The results, taken from simulations carried out by the authors, show good agreement with the data available in the literature.