An improved Zwart-Gerber-Belamri model coupled with a k-ε turbulence closure was employed to simulate cryogenic cavitating flows in a Venturi tube. The influences of cavitation number, pressure ratio (P₂/P₁) and length-to-diameter ratio (Aᵣ=L₀/R₀) on liquid-nitrogen cavitation were isolated by a control-variable approach and compared with room-temperature water. It is found that (1) lowering the cavitation number expands and intensifies the cavity, whereas increasing the number enhances condensation; (2) the pressure ratio affects nitrogen cavitation more strongly than water-under identical conditions the cavity length is shortened by 21.8 % and the vapor volume fraction is reduced by 39.1 %, indicating a faster phase transition; (3) when only the throat length is varied, a higher length-to-diameter ratio shifts the cavity downstream and intensifies mass transfer, whereas varying only the throat radius increases cavitation strength without changing the axial locations of the cavity cloud; (4) under coupled conditions the pressure ratio governs the intensity, and the strongest cavitation is produced at (a) low length-to-diameter ratio when throat length is adjusted or (b) high length-to-diameter ratio when throat radius is adjusted.
Ding et al. (Wed,) studied this question.