THE IMPACT CHARACTERISTICS OF A WATER DROPLET ON A FLAT PLATE IN TWO-PHASE, AIR-WATER SPRAY FLOW
AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING
Pagination or Media Count:
The purpose of this study was twofold to determine experimentally the impact characteristics of a water droplet impinging on a flat plate in two-phase, air-water spray flow, and to predict on the basis of known heat transfer phenomena, the effect of the impact characteristic on heat transfer. The apparatus used consisted of a vertical wind tunnel, spray nozzle, adaptor, flat plate, and pressure measuring equipment. High speed motion picture photography was employed to record the impact characteristics as well as to determine the size and velocity of each droplet. It was observed that a droplet exhibits either one of three impact characteristics bounce, bounce-splash, and splash. The particular impact characteristic of a droplet was found to be primarily dependent upon its momentum. A discussion of the predicted effect of the impact characteristics on heat transfer is included in the report. The analysis indicates that heat transfer rates are augmented by all of the observed impact characteristics, and that higher values of heat transfer may be expected with increasing droplet momentum.
- Fluid Mechanics