New mechanism and correlation for degradation of drag-reducing agents in turbulent flow with measured data from a double-gap rheometer

2018 ◽  
Vol 296 (4) ◽  
pp. 829-834 ◽  
Author(s):  
Xin Zhang ◽  
Xili Duan ◽  
Yuri Muzychka
Keyword(s):  
Turbulent Flow ◽  
Reducing Agents ◽  
Measured Data

Measurements of Bubble Rise Characteristics in Various Temperatures and Liquid Velocities

2002 ◽  
Author(s):  
Kazuhiro Torimoto ◽  
Masanori Nishiura ◽  
Tomoe Tanaka ◽  
Tomio Okawa ◽  
Isao Kataoka
Keyword(s):  
Turbulent Flow ◽  
Nuclear Reactor ◽  
Liquid Velocity ◽  
Bubbly Flow ◽  
Measured Data ◽  
Rise Velocity ◽  
Reactor Safety ◽  
Bubble Rise ◽  
Bubble Rise Velocity ◽  
Nuclear Reactor Safety

Single bubble rise characteristics in turbulent flow in a vertical circular pipe were experimentally observed. As a result, it was found that bubble rise velocity relative to the time averaged local liquid velocity decreases with the increase of liquid flowrate and that it also decreases with the decrease of the distance between a bubble and wall. Investigating the mechanisms of the reductions of relative velocity, new correlations were developed for accurately evaluating the bubble rise velocities in turbulent flow. Since the predicted bubble rise velocities reasonably agreed with the measured data, the new correlations could contribute to the improvement of bubbly flow calculations in nuclear reactor safety analysis.

CFD Analysis for the Turbulent Flow Distribution in a Fuel Assembly with the Split-Type Mixing Vanes by Using the Advanced Scale-Resolving Turbulence Models

2015 ◽  
Vol 752-753 ◽  
pp. 902-907 ◽  
Author(s):  
Gong Hee Lee ◽  
Ae Ju Cheong
Keyword(s):  
Turbulent Flow ◽  
Fuel Assembly ◽  
Turbulence Models ◽  
Measured Data ◽  
Test Facility ◽  
Detached Eddy Simulation ◽  
Axial Velocity Component ◽  
Pressurized Water ◽  
Ansys Cfx ◽  
Significant Difference

In general, the turbulent flow inside PWR (Pressurized Water Reactor) fuel assembly depends on the mixing vane configuration and the pattern of the mixing vane arrangement on the strap of the spacer grid. In this study, in order to examine the turbulent flow structure inside fuel assembly with the split-type mixing vanes, simulations were conducted with the commercial CFD (Computational Fluid Dynamics) software, ANSYS CFX R.14. Two different types of turbulence models, i.e. SAS (Scale-Adaptive Simulation)-SST (Shear Stress Transport) and DES (Detached Eddy Simulation), were used. The predicted results were compared with the measured data from the MATiS-H (Measurement and Analysis of Turbulent Mixing in Subchannels-Horizontal) test facility. Although there were locally differences between the prediction and the measurement, ANSYS CFX R.14 predicted the time averaged velocity field in the reliable level. The predicted horizontal and vertical velocity components were more in agreement with the measured data than the axial velocity component. There was no significant difference in the prediction accuracy of both turbulence models.

Biomass-based polymers as effective drag-reducing agents in turbulent flow

2022 ◽  
Author(s):  
Pavneet Kaur Bhatia ◽  
Swarnika Agrawal ◽  
I. Sreedhar ◽  
R. Parameshwaran
Keyword(s):  
Turbulent Flow ◽  
Reducing Agents

An Introduction to Turbulent Flow

2000 ◽  
Author(s):  
Jean Mathieu ◽  
Julian Scott
Keyword(s):  
Turbulent Flow

Methods for the Concentration of Bovine Ac-Globulin (Factor V)

1961 ◽  
Vol 06 (03) ◽  
pp. 435-444 ◽  
Author(s):  
Ricardo H. Landaburu ◽  
Walter H. Seegers
Keyword(s):  
Room Temperature ◽  
Barium Carbonate ◽  
Deae Cellulose ◽  
Reducing Agents ◽  
Factor V ◽  
Isoelectric Precipitation ◽  
Stabilizing Agent ◽  
Bovine Plasma ◽  
The Stability

SummaryAn attempt was made to obtain Ac-globulin from bovine plasma. The concentrates contain mostly protein, and phosphorus is also present. The stability characteristics vary from one preparation to another, but in general there was no loss before 1 month in a deep freeze or before 1 week in an icebox, or before 5 hours at room temperature. Reducing agents destroy the activity rapidly. S-acetylmercaptosuccinic anhydride is an effective stabilizing agent. Greatest stability was at pH 6.0.In the purification bovine plasma is adsorbed with barium carbonate and diluted 6-fold with water. Protein is removed at pH 6.0 and the Ac-globulin is precipitated at pH 5.0. Rivanol and alcohol fractionation is followed by chromatography on Amberlite IRC-50 or DEAE-cellulose. The final product is obtained by isoelectric precipitation.

Sign in / Sign up

Export Citation Format

Share Document