Accession Number : AD0833254

Title :   TURBULENT DIFFUSION OF SMALL PARTICLES.

Descriptive Note : Quarterly progress rept. no. 2, Dec 67-Mar 68,

Corporate Author : PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF AEROSPACE ENGINEERING

Personal Author(s) : Lumley, John L. ; Snyder, William H.

Report Date : 20 MAR 1968

Pagination or Media Count : 27

Abstract : It is the purpose of this project to determine the later diffusivity of single spherical particles in an isotropic turbulent air flow and the corresponding Lagrangian velocity autocorrelation coefficient. The particles are to vary in size, density, and in time constant, and are to have a stable wake. Results of mean flow and turbulence intensity measurements are presented. They show the mean velocity profiles to be flat and the turbulence to be homogeneous in planes perpendicular to the mean flow direction and to decay in the streamwise direction as predicted. The calculation showing what spread in particles size can be tolerated to result in an acceptable error in the correlation coefficient for the small particles is presented. The project room was made ready for the particle detection system. The timing system was matched with the trigger circuits in the flash light sources. The entire control system was set-up. (Author)

Descriptors :   (*AEROSOLS, DISTRIBUTION), REPORTS, CHEMICAL WARFARE AGENTS, DROPS, SIMULATORS, TURBULENCE, SPHERES, PARTICLE SIZE, DIFFUSION, SCATTERING, MATHEMATICAL ANALYSIS, WIND TUNNEL MODELS, INTENSITY, EQUATIONS OF MOTION, TEST METHODS.

Subject Categories : Chemical, Biological and Radiological Warfare

Distribution Statement : APPROVED FOR PUBLIC RELEASE