摘要:

An investigation was conducted to study the onset of air-entraining vortices at a horizontal intake, with and without a bellmouthed entry, when the intake was projected into the experimental flume or mounted flush with the side wall. The basic non-dimensional parameters that govern the onset of vortices at a horizontal intake in model and prototype have been derived and determined experimentally. The results of measurements are given as a set of curves, which can be used for the design of a vortex-free intake and also for the selection of appropriate model scales. The results of the measurement showed that flow conditions in an air-entraining vortex is not affected by surface tension and the viscosity of the test fluid when the radial Reynolds number, and the Weber number are larger than 3x104and 104respectively. In this case the formation of vortices depends largely on circulation, submergence head and discharge into the intake.

ISSN:0022-1686    

DOI:10.1080/00221687809499623

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

Turbulent eddies created inside wall region are assumed to be wake trails shed by low-speed fluid tongues ejected out of viscous sublayer. The assumption is corroborated by experimental evidences. As a result, it is shown that there are three kinds of those eddies: streamwise eddies, undulated eddies and annular eddies. Their properties are described. An application of those concepts to a comparison between the behaviour of Newtonian and drag-reducing flows permits to appreciate the usefulness of the proposed model for a deterministic approach to the forecasting of the structure of turbulent flows.

ISSN:0022-1686    

DOI:10.1080/00221687809499624

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

Dimensionless equations for the hydraulic conductivity of crushed rock and river gravel have been developed on the basis of approximately 1250 permeameter tests. Experimental data of a number of researches were used in the correlations. Grain sizes varied from .55 to .79 mm and pore Reynolds numbers were in the range of .001 to 20,000. The data are divided into two flow regimes and separate equations are proposed for each regime. Surface roughness is incorporated in the equations for the high Reynolds number regime. The correlations also account for the wall effect.

ISSN:0022-1686    

DOI:10.1080/00221687809499625

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

A Preston tube was used to measure shear stress distributions around the periphery of a complex channel, consisting of a deep section and one flood plain. Measurements were made with full cross-section flow and with flow confined to the deep, or channel, section. The results were used to quantify the momentum transfer due to interaction between the channel flow and that over its flood plain, demonstrating the danger of neglecting this phenomenon in complex channel analysis. Lateral momentum transfer throughout the channel and flood plain was compared under isolated and interacting conditions.

ISSN:0022-1686    

DOI:10.1080/00221687809499626

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

FINITE ELEMENT SIMULATION IN SURFACE AND SUBSURFACE HYDROLOGY Academic Press Inc., I l l Fifth Avenue, New York, N.Y. 10003, U.S.A. Price $ 26.50/£ 18.80 - ISBN No. 0-12-556950-5

ISSN:0022-1686    

DOI:10.1080/00221687809499627

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

ISSN:0022-1686    

DOI:10.1080/00221687809499622

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor