Welcome to CRAFT-Tech

An innovative and advanced cavitation model has been developed for the CRUNCH CFD^® code, that addresses many of the primary requirements required for high-fidelity unsteady cavitation simulations in real fluids with variable properties. It features a generalized compressible framework that permits temperature dependent properties. It has been rigorously validated for cavitation in cryogenic fluids where thermal effects due to evaporative cooling from vaporization are significant and can result in substantial reduction of vapor pressures. The numerical framework is an acoustically accurate formulation that accurately models the sound speed in both the liquid as well as the bubbly two-phase mixture based on the local mixture composition. Furthermore, an unsteady cavitation model for the phase change has been developed that couples bubble dynamics with the hydrodynamics; it characterizes both the number density and mean bubble radius in dense vapor clouds and has been demonstrated to yield unsteady pressure fluctuation data and mean cavity lengths for cloud cavitation problems. The cavitation model in CRUNCH CFD^® has been used to compute the performance of liquid rocket inducers. Mean performance is predicted well, with both the cavitation breakdown point and the subsequent change in the slope of the performance curve showing good agreement with data.

Cavitation Zone Evolution

Simplex Performance at Design Flow Rate

Configuration and Condition Details:

Diameter: Tip : 6 inches, Hub: 2.4 inchTip gap: 0.03 inches
RPM: 5000, Flow Rate: 909 gpm,
Flow coefficient: 0.094
Water temperature: 80 degrees F
Inlet Press Range: 3-30 Psia,
Nss Range: 0-30000

Simplex Inducer Simulations