Experimental Study on Deposition Promotion and Erosion Control for Pit Collapse

2012 ◽  
Vol 204-208 ◽  
pp. 3022-3027
Author(s):  
Qiang Ying ◽  
Sheng Ying Yuan
Keyword(s):  
Experimental Study ◽  
Flow Pattern ◽  
Erosion Control ◽  
Comparative Experiment ◽  
Limited Effect ◽  
Generalized Model ◽  
Emergency Rescue ◽  
Topographic Data ◽  
Proper Distance ◽  
Velocity Reduction

Based on the actual measured topographic data of the pit collapse occurred at Sanjiangkou in Nanjing, a generalized model of pit collapse is established. With this model, the experimental study of flow pattern changes is made with the schemes of crow of a tree and tetrahedron-like penetrating frames. The study shows that the scheme with crow of tree play greater effect in pit velocity reduction, so it can be used in emergency rescue project. Although tetrahedron-like penetrating frames can also reduce velocity, but too crowded arrangement make limited effect in reducing velocity, therefore tetrahedron-like penetrating frames should keep proper distance while dumping into the pit collapse. Moreover, a comparative experiment is made on the effects between the singe project (only arranging the project in the slide pit) and the combined project (contains collapse entrance project and inside project). The study experiment shows that the combined project has no obvious better effect than the single project.

Experimental study of high rate pond system treating piggery wastewater

1996 ◽  
Vol 34 (11) ◽  
pp. 125-132 ◽  
Author(s):  
Baozhen Wang ◽  
Wenyi Dong ◽  
Jinlan Zhang ◽  
Xiangdong Cao
Keyword(s):  
Experimental Study ◽  
Energy Consumption ◽  
Flow Pattern ◽  
Fish Farming ◽  
High Rate ◽  
Land Area ◽  
Piggery Wastewater ◽  
Hydraulic Flow ◽  
Pond System ◽  
Economic Analyses

The results of an experimental study conducted in a full-scale high rate pond system treating piggery wastewater at Jianfengshan Piggery, Panyu City, Guandong Province, are presented. The system consists of two advanced anaerobic ponds (AAP) in parallel, followed by an anaerobic transformation pond (ATP) and a five-cell algae-bacterial pond (ABP). The mechanism of the AAP is described and the hydraulic flow pattern analyzed. Fermentation pits (FP) built on the bottom performed very efficiently, operating like UASB in principle. A new concept of ATP is advanced, based on its ability to transform poorly degradable materials to more easily degradable ones. It was found in the study that the HRP system was more efficient, more reliable and saved 40% land area compared with a conventional pond system. Economic analyses of both the energy consumption and the benefit to the pond system of fish farming are also included in the paper.

scholarly journals Experimental Study of Pipes Extrusion Process by Using Method of Coordinate Grids

2018 ◽  
Vol 7 (3) ◽  
pp. 58
Author(s):  
Kosmatskiy Yaroslav Igorevich ◽  
Al-Khuzaie Ahmed Saleem Oleiwi ◽  
Al-Jumaili Mohammed Jasim Mohammed
Keyword(s):  
Experimental Study ◽  
Flow Pattern ◽  
Metal Flow ◽  
Extrusion Process ◽  
Deformable Material ◽  
Contact Surfaces ◽  
Pipe Extrusion

The paper presents the results of an experimental study of the pipe extrusion process using the method of coordinate grids. The estimation of influence of separate conditions of friction on the contact surfaces of the deformable material and the pressing tool on metal flow pattern. The calculation of the forming operation is made for extrusion process stages.

Computational fluid dynamics with stents: quantitative comparison with particle image velocimetry for three commercial off the shelf intracranial stents

2015 ◽  
Vol 8 (3) ◽  
pp. 309-315 ◽  
Author(s):  
Pierre Bouillot ◽  
Olivier Brina ◽  
Rafik Ouared ◽  
Hasan Yilmaz ◽  
Karl-Olof Lovblad ◽  
...  
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Flow Pattern ◽  
Laser Sheet ◽  
Time Lag ◽  
High Porosity ◽  
Velocity Reduction ◽  
Commercial Off The Shelf ◽  
Particle Imaging ◽  
Low Porosity

Background and purposeValidation of computational fluid dynamics (CFD) in stented intracranial aneurysms (IAs) is still lacking, to reliably predict prone to occlusion hemodynamics, probing, in particular, velocity reduction, and flow pattern changes. This study compares CFD outcome with particle imaging velocimetry (PIV) for three commercial off the shelf (COTS) stents of different material densities.Material and methodsThe recently developed uniform and high precision multi-time lag PIV method was applied to a sidewall aneurysm before and after implantation of three COTS stents with high, intermediate, and low material densities. The measured laser sheet flow patterns and velocity reductions were compared with CFD results and correlated with stent material density.ResultsVelocity reduction was in good agreement for unstented high and low porosity stented IA, while flow pattern change was fully matched for unstented and high porosity stented IA. Poor CFD–PIV matching in IA was found for intermediate porosity stents.ConclusionsCFD reproduced fully PIV measurements in unstented and high porosity stented IAs. With low porosity stents, CFD reproduced velocity reduction and high velocities close to the neck, while a marked mismatch on sluggish flow was found at the dome. CFD was unable to match PIV with intermediate porosity stents for which hemodynamic transition occurred.

An Experimental Study on Air-Water Two-Phase Flow Patterns in Pebble Beds

2010 ◽  
Vol 132 (4) ◽  
Author(s):  
Bai Bofeng ◽  
Liu Maolong ◽  
Su Wang ◽  
Zhang Xiaojie
Keyword(s):  
Experimental Study ◽  
Flow Pattern ◽  
Test Section ◽  
Slug Flow ◽  
Annular Flow ◽  
Two Phase Flow ◽  
Flow Patterns ◽  
Phase Flow ◽  
Two Phase ◽  
Flow Pattern Transition

An experimental study was conducted on the air-water two-phase flow patterns in the bed of rectangular cross sections containing spheres of regular distribution. Three kinds of glass spheres with different diameters (3 mm, 6 mm, and 8 mm) were used for the establishment of the test section. By means of visual observations of the two-phase flow through the test section, it was discovered that five different flow patterns occurred within the experimental parameter ranges, namely, bubbly flow, bubbly-slug flow, slug flow, slug-annular flow, and annular flow. A correlation for the bubble and slug diameter in the packed beds was proposed, which was an extended expression of the Tung/Dhir model, Jamialahmadi’s model, and Schmidt’s model. Three correlations were proposed to calculate the void friction of the flow pattern transition in bubble flow, slug flow, and annular flow based on the bubble model in the pore region. The experimental result showed that the modified Tung and Dhir model of the flow pattern transition was in better agreement with the experimental data compared with Tung and Dhir’s model.

Experimental Study on the Flow Mitigation Characteristic of Sub-Water Permeable Spur Dike

2014 ◽  
Vol 926-930 ◽  
pp. 565-570
Author(s):  
Cheng Tao Huang
Keyword(s):  
Experimental Study ◽  
Drag Force ◽  
Fundamental Theory ◽  
Generalized Model ◽  
Spur Dike ◽  
Hydraulic Condition ◽  
Flume Tests ◽  
Permeability Characteristic ◽  
Lower Capacity

Methodology to evaluate the permeability characteristic of porous spur dike based on the fundamental theory of permeability is established. The series of flume tests were carried out and the permeability characteristic of porous spur dike was studied through testing of the proposed generalized model. Results indicate that for the porous spur dike with lower capacity of permeability, the generated resisting force when water goes through the spur dike can be divided into the drag force and the permeability force. Given the specific hydraulic condition and pattern of spur dike, the permeability force cannot be ignored, thus the porous spur dike with some permeable capacity can more effectively block the water in-flow compared with solid revetments.

Sign in / Sign up

Export Citation Format

Share Document