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(Simulation of separation is not the purpose of this article) Launch Vehicle Data The pilot launch vehicle is a single-stage solid propellant rocket with 104 seconds of burning time.
Simulating Flight Path Data processing by standard three degree of freedom simulation provides flight path, pitch angles and Mach number are extracted for power-on phase.
According to flight simulation outputs, pressure distribution in different Mach numbers is obtained by using FLUENT software CFD simulation.
Assumptions used for the simulation is as follows: To achieve more accurate results in performed simulations, the k-ε-RNG turbulence model is used.
In the simulation, the density is calculated using the ideal gas law.

Liquid-solid Hydrocyclone Numerical Simulation and Separation Efficiency Analysis Xian-ming SUN1,a*, Lei WEI2,b 1School of Materials Science and Engineering, Wuhan Institute of Technology, Wuhan 430073, Hubei, China 2School of Mechanical and Electrical Engineering, Lanzhou University of Technology, Lanzhou 730050, Gansu, China awuhansunshine@163.com, b715480807@qq.com Key words: Hydrocyclone; Numerical simulation; Turbulent kinetic energy; Separation efficiency Abstract: This paper analyses the basic structure and the separation theory of hydrocyclone.
Three-dimension spiral flow theory and CFD method was used to simulate the Φ75mm hydrocyclone.
Results of numerical simulation shows that with the inlet velocity range from 1 to 5m/s and the particle diameters range from 2 to 5um, the hydrocyclone separation efficiency is increasing.
Hydrocyclone simulation Hydrocyclone model establish The hydrocyclone simulation mainly contains establishing physical model, mesh the physical model, confirm the boundary conditions and analysis the results.
Fig. 1 The hydrocyclone structure Fig. 2 The meshing sketch Simulation results and analysis The static pressure in different planes of hydrocyclone was shown in Fig. 3.

The study methods mainly include numerical simulation and experimental study.
Due to the advantages such as fastness, accuracy, low cost and strong operability and so on, the numerical simulation is widely applied.
Simulation object and model establishment Type of transfer stations.
Simulation object.
The physical model is seen in figure 1, and numerical simulation study is conducted on the smoke diffusion rule by adopting CFD simulation software ANSYS CFX11.0 when the fire occurs.

And fluent 6.3 has been used to perform the simulation as the solver.
Fig. 2 shows the simulation result for case 1, case 2, case 3, case 4, and case 5.
And then in Fig. 2 the last two pictures show that simulation results for case 4, case 5.
Since the flow characteristics and turbulence kinetic energy are difficult to observe, the CFD studies can be an useful tool for researching the performance in the modern life.
Zhang: CFD Studies on the air flow in a double-grate biomass fired boiler (IEEE Computer Society, China 2010) [8] Y.B.

,LTD, China albj86868@163.com, b498959126@qq.com, c1020066580@qq.com Keywords: Double-channel with double-suctionpump, Impeller, Volute, Matching Abstract.In order to study the matching optimization of the impeller and volute as well asthe flow characteristics ofdouble-channel with double-suction pump ,this paper based on CFD performance prediction method uses the same impeller to match the volute with different base diameters, guaranteeing the volute inlet width, flow cross-sectional area, and tongue position unchanged .The calculation results show that scheme A with the largest volute base diameter can not only achieve theexcellent energy characteristics and the velocity-pressure uniform distributions, but also the exchange of the fluid energy is more sufficient in the volute.
Because of the above reasons, this paper based on CFD performance prediction method and predecessors' research results, using the same impeller to match different base diameter volutes,study the influence of different base diameter volutes for the internal flow characteristics of the double-channel with double-suction pump.
As can be seen from the Q-H curve, the changingtendency of the simulation and experimental values are basically the same.
In the optimum condition point, the simulation head is 12m, the experimental head is 11.74m.The relative error of the simulation and experimental values is 2.3%.
From the Q-η curve can be seen, the simulation value is slightly higher than the experimental value, which is due to the numerical simulation not considering the pump volume losses and the friction losses between the water and the plate, etc.

The boundary layer separation is (given by CFD prediction) at s/smax = 66%.
The separation of the boundary layer occurs (by the CFD prediction) at the same point.
For t/c = 0.6 the integral values of KEL obtained by CFD are ¼ lower compared to experimental data (Fig. 4).
The numerical simulations predict that there isn´t any transition in boundary layer for all cases without boundary layer separation.
The small differences in the trends of KEL as a function of Mach number in comparison with experimental data were discovered, when the numerical simulations predict the slight increase of KEL with increasing Mach number.

The feasibility of numerical simulation Physical model and meshing.
A 3D mesh model is created by GAMBIT software for CFD simulation.
According to the experiment, this simulation use air as flow medium and adopt standard κ-ε turbulent model to calculate.
Numerical simulation method is feasible when it is difficult to do experiments due to venue, money ,etc
The computational fluid dynamics analysis-CFD software principle and application [M].

Taking the air intake pipe in the engine as the target of the research, the software STAR-CDE is adopted to build a three-dimensional simulation model for the air intake pipe in the engine T12V190 with the aim to solve the problems of air input deficiency, Combustion deterioration and performance reduction of one cylinder caused by the non-uniformity.
Moreover, the non-uniformity of the flux of air intake of the air intake pipe is mainly studied and analyzed through a calculation on the CFD of the inner flow field of the three dimension of the air intake pipe in the engine T12V190.
In this paper, taking the STAR-CD V3.26.059 (abbreviated as STAR-CD in the following) and Fortran as the tools software, correlative modules of STAR-CD are adopted to complete the partitioning of lattice, enactment and derivation of the boundary condition and initial condition, and Fortran is used to be the user program to control the turn-on and cut-off of the each outlet, through a calculation on the CFD of the inner flow field of the three dimension of the air intake pipe in the engine T12V190.
Engine intake flow simulation and optimization [J].Chinese Internal Combustion Engine Engineering, 2005, 26(4) page: 12-15
Application of CFD / CAD technology to optimize the design of diesel engine intake pipe [J].

Seshadri has applied CFD technique to study the relation of oval shape and press loss in Annubar Flowmeter[2].
There are three kind of flow field numerical simulation method namely direct numerical simulation, Reynolds statistical average model, turbulent large eddy simulation.
The basic simulation method is to carry out the direct numerical simulation to the large eddy and the simulation to the small eddy with the model.
Simulation Model and Boundary Conditions.
The simulation model is shown in Fig. 2.

With the development of computation fluid dynamics in recent years, the method of numerical simulation are used to calculate the added mass.
Shan, A new numerical computational method for added masses of complicated object, Computer Simulation, Vol. 24 (2007), p. 171-176
Li, Numerical studies of added mass based on the CFD method, Journal of Harbin Engineering University, Vol. 32 (2011), p. 148-152
Lu, Hydrodynamic numerical computation of the added mass of elastic body and cavitation bubble, Compute Simulation, Vol 27 (2010), p. 349-354
Yu, A computational method for evaluation of added mass and damping of ship based on CFD theory, Journal of Shanghai Jiaotong University, Vol. 43 (2009), p.198-203.