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The conclusions will provide the basis and reference for the performance prediction of axial-flow pumps based on CFD.
The numerical simulation and performance prediction of the internal flow of axial-flow pump bases on CFD could reduce or even replace the model test which has a high cost and a long cycle.In recent years, the numerical simulation of the internal flow of axial-flow pumps based on RANS equation has been widely used in flow analysis of axial-flow pump models, optimization of inlet and outlet runners of pump station and so on.
Numerical simulation method Governing Equations.
The second order implicit scheme is adopted for the turbulent simulation.
The calculation results of steady simulation are showed in Table 1.

The simulation is running at 0.1 Mach number or about 35 m/s.
All results are obtained from CFD simulation.
Fig. 1: UiTM’s BWB UAV Baseline-II E-4 with deflected split drag flaps on right wing Fig. 2: Direction for positive sideslip CAD Model and CFD Simulation Procedure The drawing of the BWB has been executed under CATIA V5R20.
The simulations are executed from 0° to 30° sideslip angles (b).
Curves of CD, CS, and Cn obtained from CFD simulation are observed and discussed.

The Research of the Servovalve Noise Yuan zhang Chen1,a, Da ping Gong2,b 1 Nanjing Engineering Institute of Aircraft Systems, Aviation Key Laboratory of Science and Technology On Aero Electromechanical System Integration , Jiangsu, Nanjing 2 Nanjing Engineering Institute of Aircraft Systems, Jiangsu, Nanjing a yuanzhang0609@sina.com,b gdp@avic.com Keywords: CFD; servovalve; flow-induced vibration (FIV);noise; hydro-oscillation force Abstract: Use Gambit and Fluent to the servo valve armature component of squeak problem undertook CFD is analyzed, simulates the flow field distribution in internal circuit structure, found in the servo valve armature component whistle when fluid in the inner of the product, produced a marked a negative pressure zone, and in this context the armature assembly stress sharply change, causing the armature assembly vibration squeal, changing the internal structure of the product again CFD simulation, negative pressure area disappeared, the pressure change
The paper is based on CFD technology, it will study and analysis the problem that flexure tube whistle in batches occurs during the manufacture process of a type of servovalve, and make appropriate solution, to eliminate the servovalve howling by using CFD technology. 1 Test Procedure In the paper the armature component structure is shown in Figure 1, the armature plays the role in driving of the servovalve, the flexure tube is employed to play the role not only in a spring support for armature-flapper assembly but also in a sealing between electromagnetic and hydraulic parts, deflector distribute liquid flow.
Analysis on the phenomenon. 2 CFD Solution In the test, the armature vibrates so much as produces noise just because of flowage, it belongs to the classical flow-induced vibration problem, basic equation is:
In the experiment , as the structural component the armature component is the stock-still part, it can’t vibrate because of itself machine movement, so the nonlinear item is able to ignore and just considering of the hydro-oscillation force .[1] It can obtain hydro-oscillation force by CFD.
Figure 15 Geometry of the profile Figure 16 The pressure along axis Installed the structural-change experimental sample on the test bench, then run a test, 5 pieces of the armature test-components did not produce a vibrating howling, and in the whole process of the servovalve installation and debugging, it did not appear servovale high-frequency howling phenomenon. 3 Conclusions 1) the paper reproduces the servovalve flexure tube howling phenomenon by experimental simulation, it provides the experimental basis for the theoretical analysis. 2) it simulated the flow field distribution of servovalve armature component through Gambit, Fluent software, founded that when there was high-frequency whistle in servovalve armature component, there would produce a obviously negative pressure region in the internal armature component, and with a great deal of pressure drag and flow - Induced vibrations. 3) in the paper it changed the product’s internal structure, simulated again through CFD

At present, with the development and mature of CFD technology, CFD is more and more applied in engine.
In this paper, it adopts large Reynolds number turbulence model for cooling water jacket of flow numerical simulation.
Make numerical simulation for the cooling water jacket flow in Large Reynolds number turbulence modelin this paper.
Conclusion Due to the CFD techniques become more mature and computer ability of the rapid increase, the application of CFD numerical simulation technology can guide engine jacket optimization design of structural design so as to ensure high efficiency, rationality and reliability[7].Now,we can get some conclusion as follows: (1) The pressure distribution of the cooling water jacket in the engine improved is reasonable and well relative to the previous
CFD Calculation and analysis of cooling jacket flow and heat transfer for car engine [J] .

Mixer geometries have also been optimised with the use of CFD, for instance with respect to the twist angle of solid elements of the Kenics mixer [4].
In our simulations, an entrance and exit section of 0.05 meters is added to the pipe to assure well-developed flow into and out of the mixer region.
The flow during the simulations was assumed to be three dimensional, steady and incompressible.
(1) Comparison with literature data In order to verify the validity of the proposed correlation obtained from CFD simulations, we compared it with several correlations available in the literature.
Conclusions It can be conclude from the CFD simulation that the pressure drop increase with the increase of element number and the pressure drop per element is independent of element number.

Numerical Simulation and Vibration Analysis of Inner Flow Field for Lage-sized Throttle Valve Guoqin Huanga , Ying Heb, Jin Yuc State Key Laboratory of Mechanical Transmission, College of Mechanical Engineering, Chongqing University, Chongqing, 400030, China ahgtree@163.com, bheying8706@163.com, cyj93@163.com Keywords: throttle valve; CFD; inner flow field; vibration Abstract.
Based on the computational fluid dynamics(CFD) technique, the three-dimensional inner flow field of a large-sized throttle valve was built and the dynamics characteristics of the control valve were analyzed.
Fig.2 Simulation model Fig.1 The 2D structure diagram of the throttle valve Mathematical models Control equations.
Analysis of simulation results Fig. 3 and Fig. 4 showed the velocity contour and pressure contour when valve was 50% opening.
(4) The three dimensional inner flow field of the throttle valve is simulated by means of CFD, which provides details of the reference data for channel optimization and designing this type of throttle valve.

Computational fluid dynamics (CFD) simulation technique is a scientific technique that allows improvement of cleanroom configuration without interfering with normal processes.
Zhang [6] investigated the biological contaminant control strategies under different ventilation models in the hospital operating room by using CFD simulation.
The dispersion of infectious particles from both surgical team and patient were examined through CFD analysis.
A commercial CFD code, STAR-CD [8], was used to simulate the airflow of operating room.
The performance improvement strategy with a physical partition curtain could be assessed and identified through the technique of CFD simulation for airflow distribution and the concentration decay calculation at specified monitoring points.

CFD STUDIES ON VELOCITY DISTRIBUTION OF AIR IN A SWIRLING FLUIDIZED BED Mohd Faizal1,2a*, Suzairin Md Seri1,2b, Mohd Al-Hafiz1 & Vijay R.
Methodology Investigation of the air flow distribution in a SFB was conducted using commercial CFD software – FLUENT 6.3.
Fig. 2 SFB actual system and computation domain in CFD Periodic Boundry.
Simulation of a SFB on actual scale will result high computation time.
Result and Discussion Computational time for the whole simulations took 15.17 hours.

A 2D CFD numerical method based on loose coupling algorithms was adopted to simulate vortex induce vibration of a spring-mounted cylinder.
Obviously, two-dimensional numerical simulation is the basis of "strip theory approach".
Much of the numerical errors mainly result from aspects of the problem solution, such as the procedure of iteration, the grids and time step size in most CFD simulation cases.
The hydrodynamics in each sub-step of CFD calculation can be worked out by the integral form of the surface force passed to the rigid body motions.
A 2D CFD numerical method based on loose coupling algorithms was adopted to simulate vortex induce vibration of a spring-mounted cylinder.

The Computational Fluid Dynamics (CFD) is for solving the flow and heat transfer problem[2].
CFD research has more merits like low cost and high speed compared to the experimental research .At the end of the 1960s, the CFD technology has applied in industry related to fluid mechanics widely[2].
CFD has a wide range of applications in many of the heat sterilization process of juice.
Fig.1 mesh of orange juice in tin Fig.2 the initial stage temperature of juice Cooling Process CFD Simulation of Orange Juice Maximum Temperature of Orange Cooling Process.
In the transient cooling process simulation, the temperature between the center point and the wall point was different, which indicates that heat transfer needed times to make the orange temperature filed uniform.