Numerical study on hydrodynamics and heat transfer of droplet arrays at intermediate Reynolds numbers

Thesis/Dissertation · Fri Jan 01 04:00:00 EST 1988

OSTI ID:6651490

Chem, J S

The objectives of this research are: (1) to investigate the effect of droplet spacing on the vaporization characteristics of individual droplet in a liquid fuel spray; (2) to obtain a mathematical relationship between transfer rates and local ambient properties. The result can be used as in put for a complete liquid spray analysis. A three-droplet array in a cylindrical duet has been used. The Navier-Stokes equations in vorticity-stream-function form and the energy equation have been solved numerically by using finite difference method for Reynolds number range of 10 to 200. Two approaches have been adopted which are: (1) the nonuniform cylindrical mesh, (2) the elliptic grid generation technique. The effects of droplet spacings on heat transfer of each individual droplet have been examined. Also, Nusselt number correlations for both the vaporizing and the nonvaporizing droplet array cases have been obtained. The effects of lateral and longitudinal spacings have been examined. As lateral spacing decreases in the array, the flow field accelerates and Nusselt number increases. As longitudinal spacing decreases, droplets are protected by the wakes of other droplet and Nusselt number decreases. The results show that the correlations obtained from different approaches are in close agreement. However, the correlations obtained in the present study are based on some assumptions and are by no means universal. They are derived for parameter ranges which are considered to be relevant to spray combustion. Finally, certain research problems which are related to the present study are suggested for future studies.

• Research Organization: Texas Univ., Arlington, TX (USA)
• OSTI ID: 6651490
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400800* -- Combustion
Pyrolysis
& High-Temperature Chemistry
CHEMICAL REACTION KINETICS
COMBUSTION KINETICS
DROPLETS
ENERGY TRANSFER
EQUATIONS
EVAPORATION
FINITE DIFFERENCE METHOD
FUELS
HEAT TRANSFER
ITERATIVE METHODS
KINETICS
LIQUID FUELS
MATHEMATICAL MODELS
NUMERICAL SOLUTION
NUSSELT NUMBER
PARTICLES
PHASE TRANSFORMATIONS
REACTION KINETICS
REYNOLDS NUMBER
SPACE DEPENDENCE