40. MODELING OF FLOW THROUGH A VERTICAL PERFORATED PIPE IN THE BEACH, AND THE MORPHODYNAMIC INTERPRETATION: THE PRESSURE EQUALIZATION MODULE SYSTEM

Abstract A theoretical analysis is made of the flow through a perforated pipe with a closed end for the special case of a constant linear rate of discharge along the length of the pipe. The results of the fluid-flow considerations are applicable to many practical manifold systems. The practical significance of the results with respect to pipe burners for gaseous fuels is emphasized as the results make possible the design of simple high-capacity and extended-range pipe burners of industrial importance. The capacity of commercially available pipe burners may be increased several hundred per cent. The validity of the theoretical results was verified by experiment.

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Large-Eddy Simulations of Flow Induced Vibrations in a Vacuum Flasher Unit

Computational Technologies for Fluid/Thermal/Structural/Chemical Systems With Industrial Applications, Volume 1 ◽

10.1115/pvp2002-1576 ◽

2002 ◽

Author(s):

D. K. Tafti ◽

R. G. Menon

Keyword(s):

Coming Out ◽

Flow Dynamics ◽

Large Eddy Simulations ◽

Vibrational Modes ◽

Open Area ◽

Overhead Lines ◽

Large Eddy ◽

Flow Induced Vibrations ◽

Flow Through ◽

Perforated Pipe

Large-eddy simulations of flow through a vacuum flasher are conducted to study unsteady flow dynamics and resulting flow-induced vibrations. The objective of this study is to isolate energetic vibrational modes encountered in the vessel, and also study the effect of a “Vibration Reducer” (VR), which is found to be highly effective in practice. An energetic mode at 3 Hz is found to exist in tile overhead lines coming out of the dome of the flasher vessel. These simulations show that by placing the VR, a perforated pipe, in tile dome region, the amplitude of the 3 Hz mode can be reduced by a factor of 5, provided that the effective open area of the VR is optimized. In addition, by stabilizing the flow, these simulations predict that the VR also decreases the overall pressure drop by 35%.

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Analysis of Parameters which Affect Regularity of Air Flow in Perforated Pipe

Agricultural Engineering ◽

10.1515/agriceng-2016-0070 ◽

2016 ◽

Vol 20 (4) ◽

pp. 127-135

Author(s):

Sławomir Kurpaska ◽

Hubert Latała ◽

Dariusz Baran

Keyword(s):

Energy Equation ◽

Side Surface ◽

Correlation Equation ◽

Correlation Equations ◽

Pressure Losses ◽

Independent Variables ◽

Second Stage ◽

Flow Through ◽

Perforated Pipe

Abstract The paper presents the results of analysis which enable determination of the value of the pressure losses coefficients which occurred during air suction and flow through a perforated pipe. Knowledge on them is indispensable for determination of regularity of air suction along the considered pipe. Exiting the basic energy equation, firstly a local coefficient of pressure losses was determined and then the form of the relation for its determination in the function of independent variables was found out. In the second stage, the value of pressure losses caused by mutual crossing of two streams (axial stream and stream sucked by the side surface of a pipe) was determined. Also, for this coefficient, the form of the correlation equation including power relation between the independent variables was emphasised. The calculated values of the discussed coefficients from determined forms of correlation equations are satisfactorily compliant with the calculated values from the experiments which were carried out.

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Development of apical pits in chloride cells of the gills of Pimephales promelas after chronic exposure to acid water

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100076044 ◽

1983 ◽

Vol 41 ◽

pp. 462-463

Author(s):

Richard L. Leino ◽

Jon G. Anderson ◽

J. Howard McCormick

Keyword(s):

Confidence Interval ◽

Chronic Exposure ◽

Lake Superior ◽

Pimephales Promelas ◽

Chloride Cells ◽

Fathead Minnows ◽

Secondary Lamellae ◽

Untreated Water ◽

Water Ph ◽

Flow Through

Groups of 12 fathead minnows were exposed for 129 days to Lake Superior water acidified (pH 5.0, 5.5, 6.0 or 6.5) with reagent grade H2SO4 by means of a multichannel toxicant system for flow-through bioassays. Untreated water (pH 7.5) had the following properties: hardness 45.3 ± 0.3 (95% confidence interval) mg/1 as CaCO3; alkalinity 42.6 ± 0.2 mg/1; Cl- 0.03 meq/1; Na+ 0.05 meq/1; K+ 0.01 meq/1; Ca2+ 0.68 meq/1; Mg2+ 0.26 meq/1; dissolved O2 5.8 ± 0.3 mg/1; free CO2 3.2 ± 0.4 mg/1; T= 24.3 ± 0.1°C. The 1st, 2nd and 3rd gills were subsequently processed for LM (methacrylate), TEM and SEM respectively.Three changes involving chloride cells were correlated with increasing acidity: 1) the appearance of apical pits (figs. 2,5 as compared to figs. 1, 3,4) in chloride cells (about 22% of the chloride cells had pits at pH 5.0); 2) increases in their numbers and 3) increases in the % of these cells in the epithelium of the secondary lamellae.

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