A numerical model is developed to simulate the dynamics of the droplet-wall interaction and heat transfer mechanisms at sub-atmospheric to elevated ambient pressures, and for surface temperatures ranging from nucleate to film boiling. This is the first time a general model is developed to study these phenomena over a wide range of ambient pressures. The model provides insight to the optimal flow conditions, and droplet size distribution for best heat transfer enhancement. Simulations are provided for single stream droplet impactions, and for full conical sprays using nozzles that dispense a spectrum of non-uniform droplets. The model simulation was compared against available test data for single stream of droplets at non-atmospheric conditions, and the simulation compared favorably well with the test data.
Issue Section:
Special Section on CFD Methods
Keywords:
heat transfer,
flow simulation,
drops,
two-phase flow,
film boiling,
sprays,
nozzles,
confined flow
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.Copyright © 2005
by American Society of Mechanical Engineers
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