Analysis of transport mechanisms in dense fuel droplet sprays. Final report

Technical Report · Wed May 01 04:00:00 EDT 1991

DOI:https://doi.org/10.2172/10166237· OSTI ID:10166237

Kleinstreuer, C

This report deals with numerical analyses of fluid mechanics, heat transfer, mass transfer and particle dynamics of interacting spheres and vaporizing droplets in a linear array or on a 1-D trajectory. Available finite element software has been modified and extended to solve several case studies including closely spaced monodisperse spheres with or without blowing; closely spaced vaporizing fuel droplets; and dynamically interacting vaporizing fuel droplets on a 1-D trajectory. Axisymmetric laminar flow has been assumed for three statically or dynamically interacting spherical solids and vaporizing droplets. Emphasis in this work is evaluating the effects of key system parameters, such as free stream Reynolds number, interparticle spacings, liquid/gas-phase viscosity ratio and variable fluid properties, on interfacial transfer processes and on the particle Nusselt number, vaporization rate and drag coefficient. Computer-generated correlations between integral quantities and system parameters were postulated for blowing spheres and vaporizing droplets. In addition to initial Reynolds number and droplet spacings, variable fluid properties, liquid-phase heating and internal droplet circulation have strong effect on the dynamic behavior of multi-droplet systems. While the lead droplet is most significantly affected by all key parameters, the second and third droplet causes distinct interaction effects which are largely dependent on initial droplet spacings. Applications include spherical-structure/fluid-flow interactions, as well as interacting vaporizing droplets in different sprays related to propulsion systems, irrigation, spray coating, etc. Focusing on fuel droplet sprays, results of the dynamic multi-droplet study can assist in better atomizers and combustion chamber designs which may lead to improved combustion efficiencies, smaller/lighter systems, and reduced pollutant emissions.

• Research Organization: North Carolina State Univ., Raleigh, NC (United States). Dept. of Mechanical and Aerospace Engineering
• Sponsoring Organization: USDOE, Washington, DC (United States); North Carolina State Government, Raleigh, NC (United States)
• DOE Contract Number: FG05-87ER13728
• OSTI ID: 10166237
• Report Number(s): DOE/ER/13728--4; ON: DE92018716
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
330000
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400800
42 ENGINEERING
421000
ADVANCED PROPULSION SYSTEMS
COMBUSTION
COMBUSTION SYSTEMS
COMBUSTION, PYROLYSIS, AND HIGH-TEMPERATURE CHEMISTRY
COMPUTERIZED SIMULATION
DRAG
DROPLETS
DYNAMICS
EQUATIONS
EVAPORATION
FINITE ELEMENT METHOD
FLUID MECHANICS
HEAT TRANSFER
INTERFACES
LAMINAR FLOW
LIQUID FUELS
MASS TRANSFER
MICROSPHERES
NUMERICAL ANALYSIS
NUSSELT NUMBER
PROGRESS REPORT
REYNOLDS NUMBER
SIZE
SOLIDS
SPRAYS
TEMPERATURE RANGE 0400-1000 K
TEMPERATURE RANGE 1000-4000 K
TIME DEPENDENCE
VELOCITY