摘要:

It has been widely observed that a three-dimensional wall-jet has a large rate of spread in the direction parallel to the wall and a small rate in the direction perpendicular to it. Some observations of the more general case of a jet flowing along the intersecting line of two planes reveal the same spreading along the plane. Measurements of the volume flux in a buoyant jet show that the change in cross-section is accompanied by an increase in entrainment rate but the effect is small. In most cases the increase is masked by the decrease produced by a change in the turbulent field.

ISSN:0022-1686    

DOI:10.1080/00221688509499351

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

The study ofaflowmeter patented in 1971 is presented. The apparatus is needed essentially for the flowofgas and has some very interesting features particularly in so far as linearity sensitiveness and frequency response are concerned. It can be fitted to already existing pipes needing only cheap modifications and causes no pressure drop in the flow.

ISSN:0022-1686    

DOI:10.1080/00221688509499352

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

Numerical solutions are obtained for unsteady seepage through an embankment cross section that is typical of the many flood control embankments used in New Zealand. Free surface profiles following an instantaneous drop in river level are presented in dimensionless form and are checked with a Hele-Shaw experiment. A criterion is found for assessing the applicability of the instantaneous drawdown assumption in any given application. The solutions are compared with commonly used solutions of the linearized and nonlinear Dupuit equation, and it is found that both Dupuit approximations break down because of relatively large vertical velocity components along the free surface that occur immediately after the sudden drop in river level.

ISSN:0022-1686    

DOI:10.1080/00221688509499353

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

Tojudge the consequences of pipe fracture catastrophes, knowledge of the discharge behaviour, particularly the discharge coefficient a, is required. Corresponding data were determinated fora considerable number of simulated fracture configurations. The results of experimental investigations, carried out for all geometrical and hydraulic parameters of importance, are discussed and compared with theoretical data. Finally the method of calculation is explained by an example of a particular application.

ISSN:0022-1686    

DOI:10.1080/00221688509499354

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

The problem of aggradation in a river due to overloading is tackled with a mathematical model consisting of a set of one-dimensional (in space) basic equations in which the water motion is assumed to be quasi-steady and the sediment transport is determined by local conditions. Analytical solutions are presented of a linearized simple wave model, parabolic model and the more general hyperbolic model. For large disturbances in the sediment transport an adapted solution of the hyperbolic model is obtained. Numerical computations with the complete set of basic equations learn that this solution yields better results for large and small disturbances. A laboratory experimental verification of this adapted solution shows a satisfactory agreement between the measured and calculated aggradation.

ISSN:0022-1686    

DOI:10.1080/00221688509499355

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

Detailed measurements of velocity, and of sediment transport inferred from delta build up, in a river scoured by flows up to 500 m3/s to form a 1.4 hm3delta, are used to calibrate a bed-load formula. According to this calibration, “jet zones” which occupy less than 6% of the channel area convey approximately half the load. The resulting ratings for bedload were:

ISSN:0022-1686    

DOI:10.1080/00221688509499356

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

ISSN:0022-1686    

DOI:10.1080/00221688509499350

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor