Application of Laboratory Scale Model Streams Toward Assessing Effluent Impacts in Freshwater Lotic Environments

2009 ◽  
pp. 32-32-17
Author(s):  
PP Russell ◽  
AJ Horne ◽  
JF Thomas
Keyword(s):  
Laboratory Scale ◽  
Scale Model ◽  
Lotic Environments

scholarly journals Scaling for lobe and cleft patterns in particle-laden gravity currents

2013 ◽  
Vol 20 (1) ◽  
pp. 121-130 ◽  
Author(s):  
A. Jackson ◽  
B. Turnbull ◽  
R. Munro
Keyword(s):  
Granular Material ◽  
Froude Number ◽  
Particle Diameter ◽  
Granular Flows ◽  
Leading Edge ◽  
Air Entrainment ◽  
Gravity Currents ◽  
Laboratory Scale ◽  
Scale Model ◽  
Snow Avalanches

Abstract. Lobe and cleft patterns are frequently observed at the leading edge of gravity currents, including non-Boussinesq particle-laden currents such as powder snow avalanches. Despite the importance of the instability in driving air entrainment, little is known about its origin or the mechanisms behind its development. In this paper we seek to gain a better understanding of these mechanisms from a laboratory scale model of powder snow avalanches using lightweight granular material. The instability mechanisms in these flows appear to be a combination of those found in both homogeneous Boussinesq gravity currents and unsuspended granular flows, with the size of the granular particles playing a central role in determining the wavelength of the lobe and cleft pattern. When scaled by particle diameter a relationship between the Froude number and the wavelength of the lobe and cleft pattern is found, where the wavelength increases monotonically with the Froude number.

scholarly journals Identification of a Suitable Solid Carrier as a Matrix for the Permeable Reactive Barrier of Laboratory Scale Model Aquifer for Atrazine Degradation

1970 ◽  
Vol 25 (1) ◽  
pp. 119-128 ◽  
Author(s):  
Binita K Shrestha ◽  
Pawan Raj Shakya ◽  
MIM Soares
Keyword(s):  
Laboratory Scale ◽  
Permeable Reactive Barrier ◽  
Scale Model ◽  
Pseudomonas Sp ◽  
Reactive Barrier ◽  
Solid Carrier ◽  
Different Types ◽  
Simultaneous Loss ◽  
Static Conditions ◽  
Atrazine Degradation

Three different types of physical substrata such as sand, granualar activated carbon (GAC) and plastic macaroni beads were selected to identify a suitable solid carrier as a course matrix for the permeable reactive barrier (PRB) in a sand filled two-dimensional laboratory-scale model aquifer. An adhesion experiment was performed and tested with Pseudomonas sp ADP (PASP) under agitated as well as static conditions. In static conditions, adhesion to GAC was the highest (80%) followed by that to beads (60%). No adhesion to sand was observed under static or agitated conditions. Since atrazine is adsorbed by GAC, its bioavailability for degradation by PADP may be affected. To test this, simultaneous loss of atrazine and release of chloride (dechlorination, the first step in the pathway of atrazine degradation by PADP) were determined in the presence and absence of GAC. Although cells remained viable, no significant chloride release was detected. Thus, plastic macaroni beads were identified and selected as the most suitable support for PADP in the biological permeable reactive barrier (BPRB) of the model aquifer.Key words: Suitable Solid; Laboratory Scale; PADPTribhuvan University JournalVol. XXV, No. 1, 2005Page:119-128Uploaded date: 26, September, 2010

scholarly journals First results of pipe pile static load test in small laboratory scale

2018 ◽  
Vol 251 ◽  
pp. 04038 ◽  
Author(s):  
Michal Baca ◽  
Jaroslaw Rybak
Keyword(s):  
Static Load ◽  
Axial Loading ◽  
Laboratory Scale ◽  
Load Test ◽  
Scale Model ◽  
Small Scale ◽  
Small Laboratory ◽  
Static Load Test ◽  
First Results ◽  
Load Tests

Presented laboratory testing program of tubular steel piles is a part of a bigger research program which contained static load tests in full scale and numerical simulations of conducted research. The main goal of the research is to compare static load tests with different working conditions of a shaft. The presented small scale model tests are the last part of the research. The paper contains the testing methodology description and first results of model pile axial loading. The static load tests in a small laboratory scale were conducted in a container filled with uniformly compacted medium sand (MSa). The first results of the investigation are presented in this paper, with the comparison of two pile capacities obtained for different roughness of the pile shaft (skin friction). The results are presented as load-displacement curves obtained by means of the Brinch-Hansen 80% method.

scholarly journals Laboratory-scale model of carbon dioxide deposition for soil stabilisation

2016 ◽  
Vol 8 (2) ◽  
pp. 178-186 ◽  
Author(s):  
Mohammad Hamed Fasihnikoutalab ◽  
Afshin Asadi ◽  
Bujang Kim Huat ◽  
Paul Westgate ◽  
Richard J. Ball ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Laboratory Scale ◽  
Scale Model ◽  
Soil Stabilisation

Gas-Liquid Flows in Flow Cells and Fracture Models

2008 ◽  
Author(s):  
G. Ahmadi ◽  
D. Crandall ◽  
D. H. Smith
Keyword(s):  
Multiphase Flows ◽  
Fractured Rock ◽  
Fractal Dimensions ◽  
Flow Cell ◽  
Immiscible Fluids ◽  
Laboratory Scale ◽  
Scale Model ◽  
Computational Domain ◽  
Computational Results ◽  
Liquid Flows

Gas-liquid multiphase flows in porous media and fractured rock is of importance when carbon-dioxide displaces brine within geological reservoirs during CO2 sequestration activities. In this paper, experimental and computational modeling of multiphase flows in a porous flow cell and a modeled fracture are described. The experiments performed with the laboratory-scale flow models are described in detail. Experimental data concerning the displacement of two immiscible fluids in the lattice-like flow cell are presented. The flow pattern and the residual saturation of the displaced fluid during the displacement are discussed. It was shown that the gas-liquid flows generate fractal interfaces, with lower fractal dimensions and higher residual saturations at low injection rates. This phenomenon corresponds to viscous and capillary fingering, and is discussed. Numerical simulations of the experimental flow cell are also presented. These are shown to be similar to the experimental results, and then varied to included different surface-fluid interactions not easily studied with the experimental equipment. Numerical simulation results for single and multiphase flows through rock fractures are also presented. A fracture geometry was obtained from a series of CT scans of fractured sandstone and used to construct a laboratory scale model and a computational domain. Computational results showed that the major losses occur in the regions with smallest apertures. These computational results are compared to flows through the experimental model. An empirical expression for the fracture friction factor was also described.

Acoustic Vibration in a Stack Induced by Pipe Bends

2003 ◽  
Vol 125 (2) ◽  
pp. 228-232 ◽  
Author(s):  
F. L. Eisinger ◽  
R. E. Sullivan ◽  
P. Feenstra ◽  
D. S. Weaver
Keyword(s):  
Acoustic Wave ◽  
Turbulent Flow ◽  
Pure Tone ◽  
Guide Vane ◽  
Acoustic Vibration ◽  
Model Tests ◽  
Laboratory Scale ◽  
Scale Model ◽  
Residential Areas ◽  
Guide Vanes

Acoustic vibration in two stack liners located inside a stack downstream of two induced draft fans occurred at high loads. Measurements confirmed that an acoustic wave developed in the fundamental diametral mode of the cylindrical stack liners. It manifested itself as a pure tone traveling through the stack to surrounding residential areas. It was suspected that turbulent flow in the pipe bends upstream of the stack and downstream of the fans was the source of the excitation. Laboratory scale model tests confirmed that the bends indeed acted as the source. Two guide vane configurations placed inside the bends were tested experimentally. The tests showed that properly placed guide vanes would reduce the acoustic levels in the stack. The paper gives a description and evaluation of the problem.

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