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Numerical Simulation of Flow Field Dynamics Characteristics for one novel Twin-screw Kneader Jing Wei1,a, Xinlong Liang1,Wei Sun1 and Licun Wang2,b 1 School of Mechanical Engineering,Dalian University of Technology, Dalian, China 2 Engineering Research Center for Waste Oil Recovery Technology and Equipment of Ministry of Education, Chongqing Technology and Business University, Chongqing, China a weijing@dlut.edu.cn, b wanglicun@163.com Keywords: Twin-screw kneader, Computational fluid dynamics (CFD), Non-Newtonian liquids, Numerical methods Abstract: The numerical simulation for dynamic characteristics of the flow field of a novel twin-screw kneader is carried out.
The numerical simulation of flow field dynamics characteristics for one novel twin-screw kneader [8-9] is studied in this paper.
The inlet boundary, velocity boundary, external surface boundary and outlet boundary of finite element model of flow field were set as in Fig. 3. 3 Numerical simulations and results analysis 3.1 Numerical simulation of pressure field distributions The simulation analysis for internal flow field of twin-screw kneader is carried out by using FLUENT software.
Luo, Numerical Simulation of Polymer Melting during Preheating in Twin-screw Extruder, Journal of Mechanical Engineering, 45(2009)46-49
White, Simulation of Non-linear Viscoelastic Flow Behavior in the Buss Kneader, Journal of Reinforced Plastics and Composites, 19(2000)756-791

This study implemented numerical simulations by establishing a fluid dynamic model to evaluate the intensity of the shear stress under various rotating speed and diameter of the shaker.
Simulation setup.
The simulation was carried out with a commercial computational fluid dynamic (CFD) software.
Rotating speed and diameter of the shaker were two independent variables in the simulation.
To evaluate the variable hydrodynamic condition in terms of the erosion from the flow acting on the surface of an MHV, the instantaneous viscous shear stresses can be obtained by the CFD model established in this work.

Based on theory of fluid-solid interaction (FSI), a three dimensional finite element computational model of blade wheel in a vehicular hydraulic retarder was built considering accurate fluid pressure and centrifugal stress with unidirectional FSI method, and viscous numerical simulation of computational fluid dynamics and then strength analysis were implemented, and the reliability of blade wheel was verified.
While for CFD and CSD analysis, the computational grids were quite different and nodes of them can not be coincident generally, so the calculation information can not be exchanged directly, then the automatic information mapping mechanism should be adopted based on ANSYS/Workbench platform involving CFX and mechanical modular.
According to the cyclosymmetric of wheels, a group of passages with one rotor and stator passage was selected as CFD computational model shown in Fig.3, and grid and boundary conditions were applied to it.
Fig.3 Model group of CFD computation with rotor and stator passages When hydraulic retarder works, especially applied with centrifugal stress rotor load is larger than stator load throughout, so the strength of rotor should be paid more attention to, and for the cyclosymmetric feature of rotor blade wheel of hydraulic retarder, solid geometry model and computational FEA model of 1/20 rotor blade wheel were shown in Fig.4.
The constraints were defined as follows: (1)periodic symmetric restrain was applied on slicing planes of 1/20 model; (2)displacement restrain was applied at hub of rotor wheel; (3)fluid pressure load derived from CFD analysis was applied on the pressure and suction surface of blade; (4)rotating speed of 2200 r/min was applied to the whole rotor wheel model, while that of stator wheel is zero.

Based on the finite volume method and the pressure-velocity coupling scheme of the SIMPLE algorithm with the standard k-ε turbulent model, a CFD software was used to solve the Navier-Stokes equations to calculate pressure and velocity of the air flow.
In this study, the finite volume method and the pressure-velocity coupling scheme of the SIMPLE algorithm with the standard k-ε turbulent model were applied by using the CFD software, FLUENT, to compute air pressure and velocity.
The approach Based on the finite volume method and the pressure-velocity coupling scheme of the SIMPLE algorithm with the standard k-ε turbulence model, this study utilized the CFD software, FLUENT, to solve the three dimensional Navier-Stokes equations to study the flow field of a partially porous aerostatic thrust bearing for its velocity and pressure.
In order to simplify the numerical simulation, the following assumptions were made for the flow field: (1).
Simulation techniques Fig. 1(a) illustrated the two-sided partially porous aerostatic thrust bearing and the thrust disk.

The influence of the capacity-increasing in the trailing-edge cutting of HL240 turbine blade Yu LIN 1,a, Shuren HAN 2,b, Min SHENG 2，c 1 School of Mechanical and Electrical Engineering ,Guangzhou baiyun of school,GuangDong, China 2 School of Electrical Engineering and Automation, JiangXi University of Science and Technology, Ganzhou JiangXi, China 3 School of Mechanical and Electrical Engineering, JiangXi University of Science and Technology, Ganzhou JiangXi, China ajxlgjd@126.com,b yuanyuan_1025@163.com, c beancurdsm@yahoo.com.cn Keywords: Francis turbine; cutting tip; capacity-increasing rebuilding; small electric station Abstract: In the precondition of calculating the flow field around the blade with the singular distribution way, the hydraulic characteristic after cutting the mixed-flow blade is calculated by CFD software , the optimum value of output in HL240-WJ50 water turbine and the influence of the flow field are found out by using that way: when the cutting measure
Flow field’s simulation The distribution situation of the flow field around the blade ’s airfoil is calculated by the singular distribution way, and the airfoil’s pressure distribution is shown in Fig.2(a), the abscissa Arc length is the arc distance of the airfoil’s each point to feed-water edge after cutting, the ordinate is the static pressure distribution of the airfoil’s each point.
NUMECA company's core software is developed on the basis of the CFD software- Europe aerodynamic numerical solver (EURANUS), the CFD is written for the European Space Agency (ESA) by the Fluid Mechanics Department of the Free University of Brussels, Belgium in the 1980s.
FINE / TURBO software package can be used for any compressible or incompressible, steady and non-steady, two-dimensional or three-dimensional viscous or inviscid internal flow numerical simulation.

The temperature boundary condition of simulation results are then entered in the CFD (Computer Fluid Dynamics) software PHOENICS to calculate internal temperature and mechanical property of the beam.
Numerical Simulation Model This paper uses Fire Dynamics Simulation (FDS) software to analyze thermal flow field of fire field, and then enter the temperature boundary conditions of simulation result in the thermal flow computation software PHOENICS to calculate temperature and mechanical properties inside the beam, in order to investigate variations in temperature and mechanical properties in the beam after undergoing a fire.
Figure 2 is a 3D dynamic simulation transient of combustion in the fire field created by FDS.
Initial temperature of the beam is set as 23℃, iteration as 100 times, and total simulation time as 12 hours.
Concrete Compressive Strength Simulation Discussion.

The three-dimensional flow field simulation of a centrifugal pump was presented by using commercial CFD code.
The simulation results of head and efficiency were compared with available experimental data, and the comparison showed that the result of the numerical simulation by RNG k-ε model had the best agreement.
So the numerical simulation has become an important tool to support pump design[1-3].
All the simulation results are lower than the experimental data.
All the simulation results are higher than the experimental data.

The results of numerical simulation were confirmed by fixed sampling method of immersed tube in goaf.
The Brief Introduction of Fluent Fluent is a kind of CFD software, it has powerful functions and can widely suitable for engineering calculation.
Fluent is the CFD Software Package which has the largest accompany in market, it can use for simulating the comprehensive flow range from incompressible to compressible height.
Considering the effect of the released gas in goaf and simulation establish easily, the No.304 goaf caving zone is set to be gas release area.
Non-equivalent caving goaf three zones study and simulation verification[J].Chinese journal of safety science,2010,20(10):37-40.

Numerical simulation based on k-e turbulence model in the same flow rate was taken using the platform.
At present, the rapid development of computational fluid dynamics (CFD) provides a strong research method to fan’s optimization design, and the widely use in engineering plays a more and more important role in saving money and shortening development cycle[1].
The general CFD analysis software is highly professional.
This is because the simulation has neglected parts of mechanical loss caused by bearing transimission, and the characteristics of numerical simulation also led to the result.
So it is very appropriate to research the fan with the simulation method.

Cold storage of gas flow field numerical simulation and verification.
Numerical simulation on temperature field in the door way of a minitype cold store.
Numerical simulation on temperature filed of a mini type cold store.
CFD simulation of heat and moisture transfer for predicting cooling rate and weight loss of cooked ham during air-blast chilling process.
CFD simulation of refrigerated disp lay cabinets.