scholarly journals Study on Concrete Stress during Construction for Large Pumping Station Flow Channel Structure under Thick-layer Pouring Condition

2019 ◽  
Vol 304 ◽  
pp. 052045
Author(s):  
Xuerui Zheng ◽  
Zhenzhong Shen ◽  
Sheng Qiang ◽  
Pu Xu
Keyword(s):  
Thick Layer ◽  
Flow Channel ◽  
Channel Structure ◽  
Pumping Station ◽  
Concrete Stress

Numerical Calculation of Triangle Circulation Drip Irrigation Emitters

2010 ◽  
Author(s):  
Xinkun Wang ◽  
Junhong Li
Keyword(s):  
Flow Rate ◽  
Drip Irrigation ◽  
Simulation Analysis ◽  
Structural Parameters ◽  
Structure Design ◽  
Flow Channel ◽  
Channel Structure ◽  
Sudden Expansion ◽  
Flow Index ◽  
Circulation Flow

Based on the hydraulic characteristics of triangle circulation, sudden-expansion pipe and sudden contraction pipe, Construct a drip irrigation emitter with strong turbulent flow, large over-current cross-section and strong anti-clogging ability. Triangular circulation flow path emitters for the key structural parameters for the factors, application of computer numerical fluid dynamics CFD software FLUENT6.3, simulate triangular circulation flow channel structure, analyze the influence of various structural parameters on hydraulic performance of emitters, flow index, flow rate and the anti-clogging ability. The results show that increase unit cusp, unit chamfer, the flow index increased, but the effect to varying degrees; inlet dimension increase, flow index reduced; flow channel depth and flow channel width increases, the discharge increases. Increase unit cusp, unit chamfered, can improve the anti-clogging performance of emitters. Based on the above results, to design an emitter structure with good performance, and its numerical simulation analysis, the flow index, flow rate and anti-clogging ability have met the requirements of drip irrigation. Provide a theoretical basis for the triangle circulation emitter structure design and quantitative analysis. The research has a positive meaning for energy conservation.

scholarly journals Effect of gas flow channel structure on the performance of an anode-supported honeycomb solid oxide fuel cell

2018 ◽  
Vol 84 (859) ◽  
pp. 17-00419-17-00419
Author(s):  
Hironori NAKAJIMA ◽  
Shunzaburo MURAKAMI ◽  
Tatsumi KITAHARA
Keyword(s):  
Fuel Cell ◽  
Solid Oxide Fuel Cell ◽  
Gas Flow ◽  
Flow Channel ◽  
Solid Oxide ◽  
Channel Structure ◽  
Oxide Fuel

Numerical Simulation for Fluid Flow of Flow Channel Structure in the Injection-Rolling Nozzle during Polymer Continue Injection Direct Rolling

2013 ◽  
Vol 834-836 ◽  
pp. 1584-1587
Author(s):  
Huai Wei Peng ◽  
Yan Lou ◽  
Yong Hu Lv ◽  
Hai Xiong Wang ◽  
Chang Sheng Wang ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Rolling Process ◽  
Flow Channel ◽  
Channel Structure ◽  
Exit Velocity ◽  
Fluid Field ◽  
Roll Casting ◽  
Casting Nozzle ◽  
Direct Rolling ◽  
New Type

IRN (injection-rolling nozzle) is the key component of the new Polymer CIDR (Continue Injection Direct Rolling) process, and it has higher requirements than the metal roll-casting nozzle. In order to achieve uniform exit velocity, a new type of structure of the flow channel which is called IRN flow channel structure is designed by combining with the two traditional flow channel characteristics, i.e. the fishtail and coat-hanger flow channel. Then numerical simulation was used to calculate the fluid field in IRN flow channel and analyze 3D flow phenomenon and characteristics. The simulation results show that it has a uniform exit velocity of the IRN flow channel with the value of about 0.06m/s.

Design Method and Numerical Simulation Analysis of Special-Shaped Centrifugal Impeller: Part I — Design Method

2020 ◽  
Author(s):  
Jian Lei ◽  
GuoLiang Qin
Keyword(s):  
Numerical Simulation ◽  
Design Method ◽  
Low Noise ◽  
Flow Channel ◽  
Channel Structure ◽  
Surface Velocity ◽  
Centrifugal Impeller ◽  
Channel Design ◽  
Flow Passage ◽  
Radial Outflow

Abstract This paper presents the design method of the special-shaped centrifugal impeller based on the streamline curvature method. Some conclusions described in this article will be thoroughly analyzed and demonstrated in the second part. The second part mainly involves case analysis and numerical simulation of performance parameters. The design of a centrifugal impeller must yield blades that are aerodynamically efficient, easy to manufacture, mechanically sound, especially low noise during running. The blade shape is generated by specifying surface velocity distributions and consists of straight-line elements that connect points at hub and shroud. The new impeller changed the channel structure from the classic radial outflow to axial outflow and removed the U-shaped diffuser flow passage. At the same time, the anti-noise technology is applied to optimize the flow channel design. The theoretical comparison between the classic centrifugal impeller and the new impeller shows that, in the aspect of energy saving, the flow field distribution of the new impeller is more uniform, gas flow loss is significantly reduced and the compressor efficiency is obviously improved. In addition, due to the noise elimination characteristics of the distributed flow passage, the noise of the new impeller is obvious lower than the traditional centrifugal impeller. But due to the complexity of the flow channel form, the flow resistance of the flow channel will increase, however this resistance increase can be controlled by the flow channel design.

scholarly journals Effect of the Flow Channel Structure on the Nanofiltration Separation Performance

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Zhi Chen ◽  
Ben Zhao ◽  
Fanglei Chen ◽  
Jianming Li
Keyword(s):  
Reynolds Number ◽  
Shear Stress ◽  
Flow Channel ◽  
Channel Structure ◽  
Separation Performance ◽  
Normal Flow ◽  
Average Shear Stress ◽  
Average Shear ◽  
Feed Channel ◽  
Channel Structures

Two kinds of newly designed feed channels, for example, a spiral and a serpentine feed channels, for a bench-scale nanofiltration module were developed to improve the filtration performance. The experiments were carried out with the modules using a commercial flat NF membrane to investigate the effects of Reynolds number (Re) and flow channel structures on the flux of permeate and Mg2+rejection. It was shown from the experimental results that although the effects of Reynolds number on fluxes were not obvious for the two new feed channels compared with a normal flow channel structure, the Mg2+rejections varied apparently with Re. The Mg2+rejections were almost the same for the modules with two new feed channels and larger than that for the module with normal feed channel. The numerical simulations of fluid flow in the three kinds of feed channels were completed at Re of 4800 to explain the phenomena. The results demonstrated that there was a secondary flow in both new feed channels, which strongly influences the Mg2+rejection. The rejection increased with increasing average shear stress at the membrane wall. The spiral feed channel was the best one among the flow channel structures investigated.

scholarly journals Study on the Key Technology of Electrochemical Machining Flow Field in Aero-Rotor Blades

2021 ◽  
Author(s):  
Liang Huang ◽  
Yan Cao ◽  
Chunlei Tian ◽  
Ruochen Zhao ◽  
Jiang Du ◽  
...  
Keyword(s):  
Mass Transfer ◽  
Liquid Phase ◽  
Flow Field ◽  
Electrochemical Etching ◽  
Electrochemical Machining ◽  
Flow Channel ◽  
Rotor Blades ◽  
Channel Structure ◽  
Liquid Phase Mass Transfer ◽  
Side Flow

Abstract With the rapid development of aerospace industry in recent years, the use of aero-rotor engine blades with new special alloy materials and high distortion and thin-walled structure has been paid more and more attention. Aiming at the problems of poor tool accessibility, serious tool loss and easy deformation of blade profile in NC milling technology, electrochemical machining can realize the processing of complex special structure products with advanced materials by means of non-contact electrochemical etching process. However, in the process of electrochemical etching, the flow channel structure of electrochemical machining affects the stability of the distribution of electrochemical etching characteristics in various parts of the machining surface and ultimately acts on the forming quality by controlling the liquid phase mass transfer process in the machining gap. Therefore, reasonable design and optimization of the flow channel is of great significance in the process of electrochemical machining. In this paper, based on the existing traditional vertical single-axis feed machining mode and combined with the traditional side flow processing blade flow characteristics, innovatively proposed two kinds of electrolyte flow schemes under the vertical machining mode; Then, based on the above two flow channel structures and the energy loss characteristics of viscous fluid during liquid phase mass transfer, a mathematical model of liquid phase mass transfer flow field is established, which combines the viscosity loss characteristics of electrolyte, and by introducing a optimized flow channel structure that combined with the characteristics of positive flow and side flow and adjusting the parameters of electrolyte inlet / outlet, the optimal design channel structure and uniform flow field of aero-rotor blades are realized. Finally, the accuracy and rationality of the proposed scheme are verified by electrochemical machining verification test, which lays a research foundation and guarantee for the feasibility and accuracy of vertical electrochemical machining machine tool in aero-rotor blades.

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