MEASUREMENT OF DIRECT-CONTACT CONDENSATION OF PURE SATURATED VAPOR ON AN INJECTION SPRAY BY APPLYING PULSED LASER HOLOGRAPHY

An application of pulsed laser holography for direct measurement of the growth of subcooled spray droplets in a pure saturated vapour is presented. The spray flow corresponds to intermediate and high droplet Reynolds numbers (100 less-than-or-equal-to Re less-than-or-equal-to 3500) while the vapour pressure is varied in a wide range of reduced pressures (0.03 less-than-or-equal-to p(r) less-than-or-equal-to 0.3). The holographic reconstructions reveal a strong relation between the vapour pressure and the spray geometry. At moderate liquid flow rate and relatively high vapour pressure, subsequent pressure increments produce dramatic changes in the spray geometry and considerably reduce the condensation rate.