Assessment of Steady-State and Transient Approaches for Simulating Flow Over a Wall-Mounted Cube

This paper presents initial results from systematic investigation of flow over a wall-mounted cube aimed at developing validated methodology for variable density flows with heat transfer effects. Following a methodical approach, isothermal flow simulations at Re ≈ˆ4440 are performed to assess temporal modelling requirements before introducing thermal complexity. Steady-state and transient simulations using OpenFOAM are compared against experimental benchmark data in the same configuration. Results show steady-state RANS overpredicts recirculation length by 56% with persistent unsteadiness, whilst transient URANS reduces error to 20% and successfully captures vortex shedding frequency in excellent agreement with experimental measurements. The validated results establish a baseline for future investigations of thermal coupling ranging from passive scalar transport to fully compressible flows, forming the foundation for comprehensive study of heat transfer modelling approaches.