On the Anisotropy of Drop and Particle Velocity Fluctuations in Two-Phase Round Gas Jets
Drops and particles in steady fully developed gas jets exhibit anisotropic radial and axial velocity fluctuations and even models of two-phase flows that use isotropic k — ε turbulence submodels generally reproduce the anisotropy. It is shown that the drop velocity fluctuations can be separated into radial fluctuations that depend mainly on gas turbulence and axial fluctuations that depend also on the drop radial motion across a mean drop velocity gradient. Drop equilibration time scales are defined and used to evaluate quantitatively the drop fluctuating velocities for different drop sizes, gas turbulence properties, and local mean drop velocity gradients.
KeywordsVelocity Fluctuation Drop Size Drop Velocity Spray Model Axial Velocity Fluctuation
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