Accession Number : ADA255681


Title :   Particle Dispersion in a Turbulent Shear Flow


Descriptive Note : Final rept. 15 May 1989-15 May 1992


Corporate Author : CALIFORNIA UNIV DAVIS DEPT OF MECHANICAL AND AERONAUTICAL ENGINEERING


Personal Author(s) : Kennedy, Ian M ; Kollmann, Wolfgang


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a255681.pdf


Report Date : 15 Jul 1992


Pagination or Media Count : 43


Abstract : A joint experimental and computational study of droplet dispersion in a round turbulent jet were carried out. Truly Lagrangian measurements of droplet dispersion were obtained with a laser scattering method. A low noise, high frequency response photomultiplier tube was used to track the location of particles as they traversed a sheet of laser light. Measurements of a single droplet at many closely spaced axial locations were obtained and were analyzed in terms of droplet times of flight to give Lagrangian statistics. The computational phase of the project consisted of stochastic simulations of droplet dynamics using the velocity statistics provided by a second order closure model for the jet flow, vortex dynamics for the initial region of the jet at infinite Reynolds number, and a large eddy simulation method for the jet flow at finite Reynolds numbers. The droplet trajectories were computed to second order accuracy in each ease. The large eddy simulation of a jet at a Reynolds number of 15,000 using the discretization error as filters showed very good results up to 40 diameters downstream.


Descriptors :   *TURBULENT FLOW , *PARTICLES , *DROPS , *NOZZLES , *JET FLOW , *DISPERSIONS , *LASER TRACKING , *SHEAR FLOW , VELOCITY , COMPUTERIZED SIMULATION , LIGHT SCATTERING , HELIUM NEON LASERS , PARTICLE TRAJECTORIES , PIPE FLOW , LAGRANGIAN FUNCTIONS , VAPORIZATION , REYNOLDS NUMBER , PHOTOMULTIPLIER TUBES , NAVIER STOKES EQUATIONS , EDDIES(FLUID MECHANICS) , LASER BEAMS , MEASUREMENT , POSITION(LOCATION) , AIR FLOW


Subject Categories : Numerical Mathematics
      Optical Detection and Detectors
      Fluid Mechanics


Distribution Statement : APPROVED FOR PUBLIC RELEASE