Numerical method of identification of the pipeline hydraulic characteristics for under turbulent flow of viscous liquids

2019 ◽  
Vol 9 (2) ◽  
pp. 137-143
Author(s):  
Khanlar M. Gamzaev ◽  
Keyword(s):  
Turbulent Flow ◽  
Numerical Method ◽  
Hydraulic Characteristics ◽  
Viscous Liquids

Turbulent Flow Through Spacer Grids in Rod Bundles

1998 ◽  
Vol 120 (4) ◽  
pp. 786-791 ◽  
Author(s):  
Sun Kyu Yang ◽  
Moon Ki Chung
Keyword(s):  
Turbulent Flow ◽  
Laser Doppler Velocimetry ◽  
Hydraulic Characteristics ◽  
Rod Bundles ◽  
Spacer Grid ◽  
Spacer Grids ◽  
Rod Bundle ◽  
Turbulence Decay ◽  
Skewness Factor ◽  
Flow Through

The effects of the spacer grids with mixing vanes in rod bundles on the turbulent structure were investigated experimentally. The detailed hydraulic characteristics in subchannels of a 5 × 5 rod bundle with mixing spacer grids were measured upstream and downstream of the spacer grid by using a one component LDV (Laser Doppler Velocimetry). Axial velocity and turbulent intensity, skewness factor, and flatness factor were measured. The turbulence decay behind spacer grids was obtained from measured data. The trend of turbulence decay behaves in a similar way as turbulent flow through mesh grids or screens. Pressure drop measurements were also performed to evaluate the loss coefficient for the spacer grid and the friction factor for a rod bundle.

Effects of Al3 +  and hydraulic characteristics on the removal and behaviour of particles in dissolved air flotation

2006 ◽  
Vol 6 (3) ◽  
pp. 89-95
Author(s):  
Jungsoo Mun ◽  
Sungwon Park ◽  
Mooyoung Han
Keyword(s):  
Turbulent Flow ◽  
Removal Efficiency ◽  
Operating Conditions ◽  
Point Of Zero Charge ◽  
Hydraulic Characteristics ◽  
Dissolved Air Flotation ◽  
Floc Size ◽  
Saturated Water ◽  
Air Flotation ◽  
Dissolved Air

The removal efficiency of the dissolved air flotation (DAF) process to separate particles from water and wastewater depends on the size and zeta potential of bubbles and particles, the solution and operating conditions, hydraulic characteristics, etc. The effects of aluminium ions and turbulent flow-produced when air-saturated water was spouted into the reactor in the DAF process, on removal and, particle behaviour were on investigated. When bubble size was similar to particle size (10–50 μm), the maximum removal efficiency was 92% in a Kaolin solution of 10−3 M Al3 +  without pre-treatment for flocculation process, and, as time passed, the floc size was observed to increase at a pH of 8, which was the condition of high removal efficiency as seen through image analysis. When the air-saturated water was spouted into the reactor, the size of particle at p.z.c. (point of zero charge) seemed to increase to form a floc due to collision effects caused by turbulent flow. Consequently, floc formation by turbulent flow in the reactor seemed to positively affect removal efficiency.

scholarly journals A Three-Dimensional Turbulent Flow Analysis Method for the Rotating Channels of a Centrifugal Turbomachine

1982 ◽  
Author(s):  
D. A. Fraser ◽  
J. H. G. Howard ◽  
W. C. Lennox
Keyword(s):  
Aspect Ratio ◽  
Turbulent Flow ◽  
Numerical Method ◽  
Flow Analysis ◽  
Three Dimensional ◽  
Center Line ◽  
Analysis Method ◽  
Solution Methods

A three-dimensional turbulent flow analysis method is described based on transformations of the equations to follow an arbitrary curved passage center-line and allowing for passage area and aspect ratio variations. The numerical method is arranged to allow either parabolic or partially parabolic solution methods in the main passage direction. The method has been tested for radial turbomachine elements and comparisons are included with measured internal passage flows in a radial impeller.

Thermal and hydraulic characteristics of a triangular duct using an Al2 O 3 nanofluid in a turbulent flow regime

2019 ◽  
Vol 48 (6) ◽  
pp. 2639-2654 ◽  
Author(s):  
Yazan Taamneh ◽  
A. E. Kabeel ◽  
N. Prakash ◽  
Ravishankar Sathyamurthy ◽  
Ali J. Chamkha
Keyword(s):  
Turbulent Flow ◽  
Flow Regime ◽  
Hydraulic Characteristics ◽  
Turbulent Flow Regime

Large-Eddy Turbulent Flow Simulation of a KOMAX Static Mixer

2008 ◽  
Author(s):  
Ramin K. Rahmani ◽  
Theo G. Keith ◽  
Anahita Ayasoufi
Keyword(s):  
Turbulent Flow ◽  
Critical Role ◽  
Flow Simulation ◽  
Reynolds Numbers ◽  
Static Mixer ◽  
Viscous Liquids ◽  
Pressure Drops ◽  
Static Mixers ◽  
Eddy Simulation ◽  
Large Eddy

Viscous liquids have to be homogenized in continuous operations in many branches of processing industries; and therefore, fluid mixing plays a critical role in the success or failure of many industrial processes. Consequences of improper mixing include non-reproducible processing conditions and lowered product quality, resulting in the need for more elaborate downstream processes and increased costs. The range of practical flow Reynolds numbers for KOMAX static mixers in industry is usually from moderate values (Re ≈ 0) to very large values (e.g. Re ≈ 5,000,000). However, most of industrial applicants have a very small flow to moderate Reynolds numbers (e.g. Re ≈ 5,000). This paper presents an improved understanding of the turbulent flow pattern for single-phase liquids through the mixer. Large-Eddy Simulation (LES) model is applied to the flow in a KOMAX static mixer to calculate the flow velocities, pressure drops, etc. Using a variety of predictive tools, the mixing results are obtained.

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