Determination of slip ratios in air‐water two‐phase critical flow at high quality levels utilizing holographic techniques

Holographic techniques employing a pulse ruby laser were used to measure the size and velocity of drops for air‐water two‐phase critical flow at quality levels above 0.95. The use of a large numerical aperture in the holographic recording system permitted diffraction limited resolution of the droplets. The measured slip ratio a long withthe observation that a very significant portion of the liquid phase was concentrated near the boundary layer at the exit plane indicates that a separated flow model describing two‐phase critical flow would represent the actual conditions to a better degree than the other models.