CFD Software & Simulation Techniques Flashcards
7 cards from real CPCE practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 CFD Software & Simulation Techniques flashcards as text
Which ANSYS meshing tool is specifically designed for high-quality boundary layer mesh generation around aerodynamic surfaces?
Answer: ICEM CFD
ANSYS ICEM CFD provides advanced blocking and structured hexahedral meshing capabilities particularly suited for boundary layer-resolved aerodynamic simulations.
In STAR-CCM+, what is the function of the 'Continua' node in the simulation tree?
Answer: Defines physics models and material properties
The Continua node in STAR-CCM+ groups physics continua (fluid, solid) and their associated models, equations of state, and material properties.
What is 'wall function' approach in turbulence modeling used to avoid?
Answer: Resolving the laminar sub-layer with fine mesh
Wall functions use semi-empirical correlations to bridge the laminar sub-layer, avoiding the computational expense of resolving it with a very fine near-wall mesh (y+~1).
Which OpenFOAM solver would you use for a steady-state incompressible turbulent flow simulation?
Answer: simpleFoam
simpleFoam is OpenFOAM's steady-state incompressible solver using the SIMPLE algorithm, suitable for turbulent flows with RANS models.
In CFD post-processing, what is a 'Q-criterion' isosurface used to visualize?
Answer: Vortical structures in turbulent flow
Q-criterion identifies vortical structures where the rotation rate dominates strain rate (Q > 0), making it a standard tool for turbulence vortex visualization.
What is the purpose of 'under-relaxation factors' in steady-state CFD solvers like SIMPLE?
Answer: Damp updates to flow variables to prevent divergence
Under-relaxation factors limit the change in field variables between iterations, stabilizing the iterative process at the cost of slower convergence.
Which meshing strategy is most appropriate for capturing tip vortex flows in rotating turbomachinery?
Answer: Conformal polyhedral mesh with tip gap refinement
Conformal polyhedral meshing with local refinement in the narrow tip gap region ensures sufficient resolution to capture the complex vortex dynamics in that region.