  This study presents a critical assessment of a pressure-based solver (PBS) in
resolving complex interactions of shocks, turbulent structures etc.. The
canonical problem chosen to be resolved in this study is of mode staging in
axisymmetric supersonic jet screech. The screech phenomenon exhibits staging
behavior characterized by frequency and azimuthal structure changes at specific
frequencies. The PBS simulations in the popular ANSYS Fluent software-suite
were validated against numerical work and experimental measurements, and
results were analyzed. Simulations are performed on supersonic jets which emits
dual high frequency screech tones at particular Mach numbers. At lower end of
these supersonic Mach numbers, the flow can involve vanishingly weak shock
strengths which is routinely captured in experiments and by density based
solvers in literature. The limitations of the pressure-based solver in
resolving complex shock flow phenomena and predicting mode staging are
highlighted at vanishingly weak Mach numbers, emphasizing the need for further
investigation given the recent popularity of such solvers for all Mach numbers
including in high-speed flow.
