scholarly journals Experimental investigation into the reduction of erosion of sand at high flow velocities

2019 ◽  
Vol 172 (2) ◽  
pp. 55-70
Author(s):  
Björn Foortse ◽  
Paul J. Visser ◽  
Rik Bisschop ◽  
Cees Van Rhee
Keyword(s):  
Experimental Investigation ◽  
High Flow ◽  
Flow Velocities

scholarly journals The Debris Content of Surging Glaciers in Svalbard and Iceland

1975 ◽  
Vol 14 (72) ◽  
pp. 395-406 ◽  
Author(s):  
Chalmers M. Clapperton
Keyword(s):  
Bottom Sediments ◽  
High Flow ◽  
Frictional Heat ◽  
Horizontal Extent ◽  
Compressive Flow ◽  
Melt Water ◽  
Terminal Zone ◽  
Trigger Zone ◽  
Vertical Development ◽  
Flow Velocities

In Svalbard and Iceland there appears to be much more debris entrained in glaciers that surge than in those which do not. Conditions particularly favourable for the basal incorporation of debris develop as a consequence of the high flow velocities attained by a surge. These are increased cavitation in the lee of obstacles and an increased supply of basal melt water resulting from frictional heat and from the trigger zone. Layers of regelation ice incorporating debris can thus develop to a much greater vertical and horizontal extent than in non-surging glaciers. Excessive shearing, and the distortion of foliation structures in the terminal zone of compressive flow, enhance the vertical development of the debris-rich regelation layers. Glaciers that surge over outwash and/or fjord-bottom sediments become particularly rich in debris.

scholarly journals Adapting the Forchheimer equation for the flow of air through wheat straw beds

2016 ◽  
Vol 20 (suppl. 2) ◽  
pp. 463-470
Author(s):  
Djordjije Doder ◽  
Biljana Miljkovic ◽  
Borivoj Stepanov ◽  
Ivan Pesenjanski
Keyword(s):  
Experimental Investigation ◽  
Pressure Drop ◽  
Wheat Straw ◽  
Measurement Methods ◽  
High Flow ◽  
Biomass Combustion ◽  
Inertial Effects ◽  
Forchheimer Equation ◽  
Flow Rates ◽  
Straw Bale

The paper presents the results of an experimental investigation of air pressure drop while flowing through wheat straw beds. According to Darcy?s law, the smaller the porosity of the bed is, the bigger the pressure drop will be. The investigation was conducted using three different porosities (or three bed densities), and for two different air flow rates. After determining porosity (which is directly measurable), the permeability of straw could be found. For high flow velocities, such as the velocity of air flowing through a straw bale, the Forchheimer equation becomes more relevant as a correction of Darcy?s law with inertial effects included. Otherwise, the permeability tensor depends only on the geometry of the porous medium. With permeability known, the Forchheimer equation coefficients can be easily estimated. These results may be important for the future development of efficient biomass combustion facilities. The measurement methods and facility characteristics are described in more detail.

Scour Around Bridge Piers at High Flow Velocities

1980 ◽  
Vol 106 (11) ◽  
pp. 1827-1842 ◽  
Author(s):  
Subhash C. Jain ◽  
Edward E. Fischer
Keyword(s):  
High Flow ◽  
Bridge Piers ◽  
Flow Velocities

Discussion of “Scour Around Bridge Piers at High Flow Velocities”

1981 ◽  
Vol 107 (7) ◽  
pp. 958-958
Author(s):  
Fred W. Blaisdell ◽  
Clayton L. Anderson
Keyword(s):  
High Flow ◽  
Bridge Piers ◽  
Flow Velocities

A beamforming method for plane wave Doppler imaging of high flow velocities

2016 ◽  
Author(s):  
Omar Mansour ◽  
Tamie L. Poepping ◽  
James C. Lacefield
Keyword(s):  
Plane Wave ◽  
High Flow ◽  
Doppler Imaging ◽  
Flow Velocities

Paper 15: Vibration of Flexible Cylinders with Supported Ends, Induced by Axial Flow

1965 ◽  
Vol 180 (10) ◽  
pp. 268-279
Author(s):  
M. P. Paidoussis
Keyword(s):  
Cross Flow ◽  
Axial Flow ◽  
High Flow ◽  
Flexible Cylinder ◽  
Empirical Expression ◽  
Flexible Material ◽  
Amplitude Vibration ◽  
Critical Velocities ◽  
Flow Components ◽  
Flow Velocities

A flexible cylinder with pinned ends in axial flow of sufficiently high flow velocity is subject to buckling and oscillatory hydroelastic instabilities. These instabilities are discussed briefly and it is shown that they occur at such high flow velocities that they are not likely to be encountered in practice, unless the cylinder is made of very flexible material such as rubber. The cylinder is subjected to small amplitude vibration, however, even at flow velocities very much smaller than the critical velocities for hydroelastic instabilities. The mechanism of energy transfer from the fluid to the cylinder is examined and it is postulated that this vibration is excited by cross-flow components of flow and other departures from steady, uniform and perfectly axial flow. Experimental evidence supporting this postulate is presented. An empirical expression is given for the amplitude of vibration based on reported experimental observations covering a variety of geometries, fluids and cylinder materials.

Sign in / Sign up

Export Citation Format

Share Document