Accession Number : ADA291696

Title :   Structure of High-Speed Sprays.

Descriptive Note : Final technical rept. 15 Dec 84-14 Feb 89,

Corporate Author : PRINCETON UNIV NJ DEPT OF MECHANICAL AND AEROSPACE ENGINEERING

Personal Author(s) : Bracco, Frediano V.

PDF Url : ADA291696

Report Date : JAN 1995

Pagination or Media Count : 119

Abstract : This work covered both measurements and computations and its results are documented in eight appendices. Measurements were made of drop velocity in vaporizing, steady, full-cone sprays and of drop velocity and drop size in non-vaporizing steady full-cone sprays. In similar conditions, measurements had previously been made of the intact core and of the size of the drops in the immediate vicinity of the injector, thus generating an extensive set of data which were particularly useful for the assessment and the development of multidimensional models of engine sprays. On the computational side, a line source technique was introduced to simulate the intact-core in engine sprays and two extensive numerical studies were carried out to explain the strong anisotropy of the drop velocity fluctuations that had been found in the measurements. In another interesting and timely study, the accuracy of the stochastic method of computing drop collisions and coalescence (which is the one universally used) was assessed by corresponding deterministic computations (more accurate but much more time consuming). It was concluded that the accuracy of the stochastic method in practical computations can be wanting. Finally, a numerical study of the structure of hollow-cone sprays was initiated that has since been followed by significant experimental and computational work on liquid-only and air-assisted hollow-cone injectors and sprays. (AN)

Descriptors :   *SPRAYS, *TWO PHASE FLOW, VELOCITY, MATHEMATICAL MODELS, EXPERIMENTAL DATA, COMPUTATIONS, STOCHASTIC PROCESSES, COMPARISON, NUMERICAL ANALYSIS, ACCURACY, TURBULENCE, PARTICLE SIZE, COALESCENCE, MASS FLOW, FLOW FIELDS, ANISOTROPY, DROPS, JET FLOW, NOZZLE GAS FLOW, VAPORIZATION, PARTICLE COLLISIONS, LASER VELOCIMETERS, AXIAL FLOW, ATOMIZATION, COMBUSTION CHAMBER GASES.

Subject Categories : Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE