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Numeric Simulation of Gas-Dynamic Processes in the Swirl Combustion Chamber in STAR-CCM+ Igor Kuksov1, a, Sergey Mochalov2, b, Vladimir Sarychev3, c 1 Department of Corporate Technologies, Siberian State Industrial University, Novokuznetsk, 654007 Russia 2 Siberian State Industrial University, Novokuznetsk, 654007 Russia 3 Department of Physics, Siberian State Industrial University, Novokuznetsk, 654007 Russia aadmin@okt.sibsiu.ru, bspm@sibsiu.ru, csarychev_vd@physics.sibsiu.ru Keywords: swirl chamber, gas-dynamic processes, swirl flow, CFD simulation Abstract.
Simulation Setup The air is supplied to the header with the mass flow rate varying from 600 to 900 m3/hour.
Simulation of fuel particles was carried out by the Lagrangian phase.
Non-stationary Reynolds-Averaged Numerical Simulations (RANS) are used in calculations.
This approach was chosen because of its greater calculating efficiency with fair accuracy for a particular task in comparison with the direct numerical simulation (DNS) and large eddy simulation (LES).

In addition, the paper designs the Coanda Effect control switch experiment, which verifies the feasibility of the Coanda Effectcontrol switch action and ensures the generation and implementation of the water hammer effect. 2Two-dimensional model of Coanda Effect control switch 2.1Two-dimensional modeling The establishment of a suitable model isthe key that the simulation result is correct based on fluent simulation.
Coanda trigger control link two-dimensional model 2.2 The 2D mesh based on CFD The 2D Coanda model is established with CFD.
Through the fluent simulation, the separation point of the hydraulic cylinder two branches should take in the distance from the initial separation point 4.5mm~6mm.
Numerical simulation of Coanda Effect in Circulation Control Airfoil[J].

The numerical method used in this simulation is an unstructured staggered mesh scheme.
These studies all reflect the accuracy of LES in simulation.
In contrast, RANS is not ideal in simulation.
Large eddy simulation of the turbulent flow past a backward-facing step[C].
Turbulence Modeling for CFD [M].

Simulation technique of screw that is used in extrusion molding has become so far various.
Therefore in this treatise analyzed heat and flow special quality of screw considering pressure, temperature distribution using three-dimensional finite element method (CFD). 1.
[6] J.B Yoon, "Simulation of Heat and Fluid Flow in the Single Screw Extruder with Coupling of the Metering Section and Die", 2000 [7] J.Y Yoon, Y.K Hwang, J.S Park, T.J Ko and J.W Park "An Integrated CAD System for Design of Extruder Screw" Journal of Korean Society of Precision Engineering Vol. 19, No. 8 , 2002

In this paper, the effects of changing under-relaxation factors for different variables on the numerical solution of 2D incompressible laminar flow over a backward-facing step (BFS) are studied using PHOENICS commercial Computational Fluid Dynamics (CFD) software.
This is conducted by changing under-relaxation factors for velocities and pressure during the 2D simulation.
In this study, 2D simulations for flow over a backward step are performed by changing under-relaxation factors for velocities (uu and uw) and pressure (up).
This will be very useful in order to achieve lower error percentage for flow variables in simulation that involves velocities (in x- and z- directions) and pressure.
Effects of under relaxation factors on turbulent flow simulations.

Numerical simulation model of trajectory without wind.
Opening canopy fully is a complicated aerodynamic process, and many scholars has done many CFD simulation and established nonlinear theory model.
Contrast analysis of testing and numerical simulation Simulation theory for trajectory of bomb with parachute at low altitude condition.
The trajectory simulation of bomb with parachute at low altitude condition can be divided into all trajectory simulation at single bombing and spread simulation of multiple bombing.
Contrast analysis of testing results and simulation data.

Therefore the numerical simulation is an important tool in fire investigation [2].
The FDS simulation results are very close to the subsequent full scale experiment which proves the feasibility of FDS simulation reappearance fire scenario.
As the research of smoke diffusion, the CFD is used to simulate the three-dimensional field.
Discussion of simulation results Two fire scenarios were set here, named scenario 1 and scenario 2.
Besides, Simulation in addition to the detection point was set for detecting temperature and smoke density changes

Introduction Buffeting response of bridge is a important problem in bridge wind engineering, the traditional method to study it is the one in frequency domain, such as Scanlan [1], Chen etc [2], Zhe Liu [3], with the development of CFD technique, the buffeting response prediction on it is worthwhile to be studied.
Since the across-flow oscillation is important to predict the buffeting response of bluff body, in current simulations the movement of bluff body is controlled in the across-flow direction, and two types of inlet boundary conditions are considered to compare the different influence of them on the flow around the square cylinder, one is the steady inlet boundary and the other is the unsteady one. 2 Descriptions of Simulation Cases The block structured grid is also used in current simulation cases, see Fig.1.
To compare the different response of square cylinder from different LES models, the standard LES, LES dynamic and LES WALE models are considered in current simulations.
And the oscillation induced by the flow of current simulations can be approximated as a narrow band response approximately after the reduced time step 100, but the whole response process is a mix-band response including the broad and narrow band.
(1) Current simulations basically capture the characteristics of square cylinder, and the FSI procedure of buffeting response simulation proposed by Zhe Liu [6] can be used in future buffeting response predication.

Fig. 1(b) presents the internal volume which was extracted for the simulation.
“Numerical simulations of a prechamber autoignition engine operating on natural gas.” 
“Numerical simulation of two-stage combustion in SI engine with prechamber.” 
Modeling of a Torch Ignition System Using One-Dimensional Model of Computational Simulation.
Simulation of pre-chambers in an engine combustion chamber using available software.

Numerical Analysis of the Influence of Different-shaped Square Cylinders on Water Flow Jie Gu1,a, Xiaoli Wang1, Wei Chen1, Xin Qin1, Danqing Ma1 and Jizhong Yang1 1 College of Marine Sciences, Shanghai Ocean University, China a jgu@shou.edu.cn Keywords: numerical simulation; flow around a square cylinder; different-shaped square cylinders; streamline; turbulent kinetic energy Abstract.
Using the finite element method, Yoshida [1] and Mu et al. [2] calculated the velocity distribution, pressure distribution and cycle spiral disturbance of the flow around a square cylinder located in the center of the flow field, computational results were in good agreement with experimental data given by [3,4].The large eddy simulation and two turbulence models based on Reynolds Averaged Navies-Stokes equations (RANS), standard k-ε model and Renormalization Group k-ε model (RNG k-ε model), are employed by Chen et al. [5] to simulate the three-dimensional turbulent flows around a square obstacle.
The discrete vortex method (DVM) was used in a numerical simulation of the flow around a square column, states of two-phase flow were calculated [6].Wang et al. [7] used Large Eddy Simulation (LES) technique to conducted quasi three-dimensional(quasi 3D) and three-dimension(3D) simulation of the velocity fields surrounding a rigid rectangular prism at the Reynolds number of 2.2×104.Huang et al. [8] used finite- volume method to simulate and analysis the flow around square cylinder with 45°and 0°coming flow.
Wang:The computational fluid dynamics analysis: theory and applications of the CFD software(Tsinghua University Press, Beijing2004) [11] B.