Journal of Basic Engineering
ISSN : 0021-9223
Published by: ASME International (10.1115)
Total articles ≅ 3,165
Latest articles in this journal
Journal of Basic Engineering, Volume 94, pp 720-728; https://doi.org/10.1115/1.3425533
The growth of planar jets is studied using the hydrogen bubble technique of flow visualization. A five-fold range of nozzle exit Reynolds number (1860 to 10,800) is considered. Generation of streaklines and timelines permits characterization of the process of vortex formation and coalescence. Both symmetrical and asymmetrical modes of vortex growth and coalescence, along with the resultant deformation of the jet core flow, are examined. Nascent and mature stage coalescence are defined and portrayed. Vortex axial transport velocity and frequency of formation of the vortices are evaluated for selected Reynolds numbers.
Journal of Basic Engineering, Volume 94, pp 748-748; https://doi.org/10.1115/1.3425540
Journal of Basic Engineering, Volume 94, pp 729-730; https://doi.org/10.1115/1.3425536
Journal of Basic Engineering, Volume 94, pp 731-738; https://doi.org/10.1115/1.3425537
Solutions for the point mean flow field properties in the turbulent core for suspension flow in a vertical circular tube have been developed for the fully developed flow condition. For uniform particle density flows, the suspension velocity distribution is logarithmic and is given in terms of parameters which must be determined by experiment, but the paper shows that all flows which satisfy the conditions of the model should follow the same universal law. Analytic expressions for the gas velocity and the slip velocity are also presented. The purpose of the analysis was to produce solutions of practical utility and to provide a basis for the extrapolation and interpretation of experimental results which are presented in another paper.
Journal of Basic Engineering, Volume 94, pp 739-747; https://doi.org/10.1115/1.3425538
An experimental investigation has been made of a swirling jet having a moderate ratio of swirling to axial momentum. Measurements showed that the flow achieved a self-similarity for the mean velocities rather quickly while the normal turbulent intensities reached a self-similar state after a longer period of jet development. Conservation arguments were used to predict streamwise decay rates for the mean quantities. The analysis showed that the maximum axial and swirling velocity components should vary asymptotically as (x − x0)−1 and (x − x0)−2, respectively. The experimental results confirmed this satisfactorily. The minimum static pressure was predicted to vary at a rate proportional to (x − x0)−4. Measurements indicated, however, that the relation was closer to (x − x0)−2. Better agreement with the data was achieved when the analytical expression was adjusted for the effect of the turbulence terms. The entrainment rate and angle of spread for the swirling jet were found to be nearly twice that of the non-swirling free jet.
Journal of Basic Engineering, Volume 94, pp 777-787; https://doi.org/10.1115/1.3425553
A visualization study of the flow through a three ft dia model of a four bladed inducer, which is operated in air at a flow coefficient of 0.065, is reported in this paper. The flow near the blade surfaces, inside the rotating passages, downstream and upstream of the inducer is visualized by means of smoke, tufts, ammonia filament, and lampblack techniques. Flow is found to be highly three dimensional, with appreciable radial velocity throughout the entire passage. The secondary flows observed near the hub and annulus walls agree with qualitative predictions obtained from the inviscid secondary flow theory. Based on these investigations, methods of modeling the flow are discussed.
Journal of Basic Engineering, Volume 94, pp 788-794; https://doi.org/10.1115/1.3425554
This paper describes an experimental investigation of two-phase, air-water nozzle flows including critical or choked flow. Five different nozzle geometries were used. The nozzles exhausted to atmospheric pressure from stagnation pressures of 16 to 55 psia. The quality (mass fraction of air flowing) ranged from 2 to 35 percent. A feature of the study was the injection system which was designed to minimize the entrainment of liquid into the gas phase. The data were found to be described within about 10 percent by modifying separated flow theory by a simple “blockage factor” correlation.
Journal of Basic Engineering, Volume 94, pp 801-802; https://doi.org/10.1115/1.3425559
Journal of Basic Engineering, Volume 94, pp 802-803; https://doi.org/10.1115/1.3425561
Journal of Basic Engineering, Volume 94, pp 810-810; https://doi.org/10.1115/1.3425564