Accession Number : ADA130706

Title :   Transverse Jet Break-up and Atomization with Rapid Vaporization along the Trajectory.

Descriptive Note : Interim rept. 1 Dec 81-30 Nov 82,

Corporate Author : VIRGINIA POLYTECHNIC INST AND STATE UNIV BLACKSBURG DEPT OF AEROSPACE AND OCEAN ENGINEERING

Personal Author(s) : Hewitt,P W ; Schetz,J A

PDF Url : ADA130706

Report Date : Jan 1983

Pagination or Media Count : 13

Abstract : A simulation approach to studying hot flow subsonic cross-stream fuel injection problems in a less complex and costly cold flow facility was developed and implemented. A typical ramjet combustion chamber fuel injection problem was posed where ambient temperature fuel (Kerosene) is injected into a hot airstream. This case was transformed through two new similarity parameters involving injection and freestream properties to a simulated case where a chilled injectant is injected into an ambient temperature airstream. Experiments for the simulated case using chilled Freon-12 injected into the Virginia Tech 23 x 23 cm. blow-down wind tunnel at a freestream Mach number of 0.44 were run. The freestream stagnation pressure and temperature were held at 2.5 atm. and 300 K respectively. The resulting spray plume was carefully examined and documented with photographs and droplet measurements. The results showed a clear picture of the mechanisms of jet decomposition in the presence of rapid vaporization. Immediately after injection a vapor cloud was formed in the jet plume, which dissipated downstream leaving droplets on the order of 8 to 10 microns in diameter for the conditions examined. This represents a substantial reduction compared to baseline tests run at the same conditions with water which had little vaporization.

Descriptors :   *Fuel injection, *Atomization, *Jet mixing flow, Transverse, Cross flow, Sprays, Simulation, Plumes, Wind tunnel tests, Jet flow, Ramjet engines, Combustion chambers, Drops, Particle size, Vaporization, Decomposition, Fluorinated hydrocarbons, Cold flow

Subject Categories : Test Facilities, Equipment and Methods
      Fluid Mechanics
      Combustion and Ignition
      Jet and Gas Turbine Engines

Distribution Statement : APPROVED FOR PUBLIC RELEASE