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Research of Flow Mechanism and Numerical Simulation on The Post-Prestressed Duct Grouting Geng Xu1,a, Renjun Yan1,b, Changlian She2 , Linzhi Xu1 ,Lin Xu 1, Fen Li1 1Wuhan University of Technology, Wuhan, Hubei, China 430063 2Beijing Zhong Ke Xin Engineering Consulting co., Ltd, Beijing, China a448087322@qq.com, byan_renjun@163.com Key words: prestressed duct; numerical simulation; design of prestressed duct; grouting speed Abstract: Post-prestressed duct grouting is a complex construction process and it is affected by many factors.
By the theoretical applicability and parameters analysis through the grouting process, this article used the numerical simulation method to analyze the grouting process and obtained the correspondence between the initial velocity, grouting pressure and grouting quality.
Through the method of finite elements numerical simulation, this article analyses the relationship between the inlet pressure, grouting speed and the molding quality.
This paper simulated the grouting process of prestressed concrete bridge, established finite element model of duct grouting, and CFD analysis method was applied to investigate non-full phenomenon in grouting process, the conclusions are followed: (1) Using the fluid motion to simulate grouting process of prestressed concrete bridge is available, and the simulation results can provide guidance for grouting construction, improve grouting technical level

The optimization of the structure and working parameters of the seeder can be realized through dynamic interference check and spatial motion path simulation for the whole sowing process[5].
Dong Chunwang et al. (2011) used CFD methods to analysis different structural forms of flow field in the chamber, and optimized the structure of the suction hole.
In recent years, along with increasing of computer operation speed, CFD software has been widely used in the refined calculation of multiphase flow field. e.g.
[5] Xia Hongmei, Li Zhiwei, Wang Hongjun: Simulation Design of the Pneumatic Plate-type Precision Seeder Based on Virtual Prototype.
[18] Li Yaoming, Zhao Zhan, Chen Jin, Xu Lizhang: Discrete Element Method Simulation of Seeds Motion in Vibrated Bed of Precision Vacuum Seeder.

Motion simulation of desulfurized fly ash in dense flow absorber based on computational fluid dynamics Qian Jia, Cunyi Song, Zhensong Tong, Donghui* Zhang, Kaihua Chen, Xi-ning Lu, Yue Zhang School of Civil and Environmental Engineering, University of Science and Technology Beijing, 100083, Beijing, China Email: jiamoney@126.com Keywords: dense flow absorber, desulfurized fly ash, sintering gas, numerical simulation, computational fluid dynamics Abstract.
This paper employed Fluent software based on Computational Fluid Dynamics (CFD) to simulate the track of desulfurized fly ash in flue gas.
In this simulation, velocity is 18 m·s-1, turbulence intensity is 2.46%, water head diameter is 3.2 m.
Fig.3 The abrasion rate gradient of inner surface and convex surface The deposition of desulfurized fly ash inside of tower body The deposition of desulfurized fly ash inside of tower body was evaluated based on numerical simulation.

The κ equation is derived in accordance with the strict equation derivation simulation, the ε equation is simulated by dimensionless analysis, analog and experience [5].
Fig 3 The three-dimensional mesh of poppet valve Fig 4 The grid in the xy plane of poppet valve 3.2.1 Simulation of Different Valve Element Internal Volume The volume of the valve plug inner cavity take V = 0mm3, 275mm3, 550mm3, 825mm3, shown in simulation diagram such as 6, 7and 8 are V = 275mm3, there are pressure, speed and kinetic energy of the poppet valve.
To sum up the valve element cavity volume should selected in the V = 275mm3. 3.2.2 Simulation of Different Valve Element Fillet The valve element fillet take R = 1mm, 1.4mm, 1.8mm, 2.2mm,when R = 1.4mm poppet valve’s pressure, velocity and kinetic energy of the simulation shown in figure such as 8, 9, and 10.
CFD Calculations of The Internal Flow Field of The Valve Element Movement of The Poppet Valve[D].Taiyuan,Taiyuan University of Science & Technology,2005
Examples and Applications of Fluid Engineering simulation[M].Beijin, Press of Beijin University of Science & Technology,2007

The experiments depicted above are simulated using CFD software FLUENT.
The correctness of the numerical model is proved by preliminary simulation with silicon-oil.
The goal of this step was to show if the simulation with this set of parameters provides the same values for the rotational velocity ω and torque M. 1 1,2 1,4 1,6 1,8 2 2,2 20 30 40 50 60 Rotational velocity ωωωω [rad/s] Torque, M [mNm] Experiment Simulation, initial set of paramters Simulation, modified set of paramters Fig. 3: Comparison of the experimental results for torque M(ω) with the numerical results using initial and modified parameter set The results of the numerical simulations are shown in Fig. 3.
The grey curve in the diagram in Fig. 3 shows the results of the simulation with the modified parameter values.
Petera: Modelling and simulation of forming processes of metallic suspensions under non-isothermal conditions, J.

In simulations without porous zone solves only the RANS equations.
On Fluent, a constant time step of 0,015625 s (T/640) used was for all simulations.
In future work, simulations will be made considering that influence.
[8] OpenCFD, OpenFOAM - The Open Source CFD Toolbox - User Guide, OpenCFD Limited, 2017
Fredsøe, A wave generation toolbox for the open-source CFD library: OpenFoam®.

In recent years, many authors have studied the fouling mechanism and the effect of fouling on gas turbine performance by CFD method or analytical model.
In the simulation of gas turbine performance, the prediction of compressor performance at various conditions is more crucial.
Simulation result analysis In order to demonstrate the validity of stage-stacking method, an 8-stage axial compressor is applied.
Simulation result shows that thermodynamic performance parameters are reduced with increase of operating time.

But the simulation images of the diffusion disciplinarian are not conveyed by image processing, the studies of two-dimensional fluid diffusion field are researched by digital image processing in this paper.
References [1] Jin Ying, Zhou Weigao and Ruan Yingjun: CFD numerical simulation of gas diffusion [J].
[2] Wang Hongwei, Liu Zhenyuan and Zheng Chuguang: Visual simulation of the gaseous pollutant diffusion models [J].

Using a simulation environment is a key tool that reducing the relevance of the problems mentioned above.
Thus, the equal operation of control system units in simulation and in real tests is realized.
Simulation of AUV environment with obstacles as well as three-dimensional visualization is a separate simulator's module.
Fig.  4: “Fault Diagnostic” view In the search process simulation indication of object recognition is implemented.
"CFD-based method for simulation of marine-vehicle maneuvering." 35th AIAA Fluid Dynamics Conference and Exhibit, Toronto, Ontario Canada. 2005.

BALL-NOSE VEHICLE'S ATMOSPHERIC PARAMETERS ESTIMATION BASED ON AIRFLOW VELOCITY Qian Lilin1,a*, Tao Jianwu1,b, Yu Fei2, Dai Haifa1 1Department of Flight Vehicle Control, Aviation University of Air Force, Changchun China 2Department of Control Engineering, Naval Aeronautical and Astronautical University Yantai China a*qianlilin1989@163.com, bjianwu.tao@163.com Keywords: Angle of attack, airflow velocity, Fluent simulation Abstract.
Fluent simulation and verification A vehicle model with a spherical nose is used for simulation in Fluent[10,11], the simulation operates at Mach numbers ranging from 0.4 to 1.6, angle of attack ranging from 0o to 30o and angle of sideslip ranging from 0o to 15o.
ANSYS ICEM CFD from learner to master[M].Beijing, Tsinghua University Press, 2013