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High-rise residential complex wind aerodynamics simulation Oleg O.
Fedosova3,c 1,2,3Moscow State University of Civil Engineering (MGSU), 26, Yaroslavskoe shosse, Moscow, 129337, Russian Federation aolenek31@gmail.com, bmgsu@broll.ru, csergdubpodlipki@mail.ru Keywords: Architecture and Construction aerodynamics, numerical simulation, wind loads, high-rise buildings, simulation of wind loads Abstract.
In this paper, the problem of the calculated characteristics giving is solved by numerical simulation, the estimated pressure indicates average components of the aerodynamic forces and moments are calculated, localization of peak pressure values are defined.
In the current design practice dominates the semi-empirical approach based on the decomposition of the velocity and pressure at the time averaged and fluctuating components and the transition to the solution of the Reynolds averaged Navier-Stokes (Reynolds Averaged Navier-Stoks Method, RANS), while shear (Reynolds) stress six unknowns are additional to the parameters of the mean flow and approximated, as a rule, by the Boussinesq hypothesis: Calculations are made of the complex aerodynamics of wind in the software package ANSYS CFD 15.0.
Using the modern numerical fluid dynamics methods, implemented in a universal software package ANSYS CFX 14.5 and specialized modules WINDLOAD / CFX, with verified three-dimensional numerical simulations average wind loads at the 36 wind directions (via 100) were determinate. 3.

Determination of the fluid loading Significant progress in the field of CFD(computational fluid dynamics) has been made, and it has been used as an efficient tool for the prediction of fluid loads.
Because Reynolds-averaged Navier–Stokes (RANS) modeling can reasonably simulate mean wind characteristics and require less computing time than other CFD methods, it is the most widely used method in many industrial applications.
For the numerical simulation, the governing equations of the incompressible turbulent wind flow around circular membrane presented by the RANS equations as follows: (4) (5) Using the dynamic mesh model in FLUENT allows for the arbitrary motion of fluid boundaries and in doing so, captures the response of the fluid to the prescribed boundary motion.

The flow and heat transfer inside the steam seal is controlled by the following equations [6]: Continuity equation: (1) Momentum equation: (2) Energy equation: (3) The CFD model of the steam seal and steam is showed in Fig. 5.
Fig. 5 The CFD model of the steam seal The flow inside the steam seal is assumed to be incompressible flow, controlled by the Reynolds averaging Navier-Stokes equations together with the continuity equation.
(3) In order to have a rapid convergence, the calculation for these simulations involve the liquid should have the calculation of the steady state first

The research method for vehicle exhaust diffuse and transport rule include experimental, theoretical analysis and numerical simulation.
Wu and Bakar[2] by using CFD software to simulation the tunnel fire with different rectangular cross section of tunnel.
In this paper, the effect of double air extraction ventilation system to CO concentration distribution and diffuse rule in large tunnel be study by numerical simulation.
Numerical simulation for smoke flow of the tunnel fire.
The zone and numerical simulation on the tunnel fire.

Simulation on Characteristics of Grinding Fluid Jet Based on FLUENT C.X.
Simulation Experiment of Air-Fluid Two-Phase Flow in Grinding Area Simulation Condition.
Plane grinding is taken as the simulation object and FLUENT is taken as the simulation software.
Considering the CFD characteristics of the flow field, in order to improve the grids quality and avoid mesh distortion and aspect ratio inconformity, body-fitted near wall grids are adopted and the grid model divided in sequence of first-line last-face is showed in Fig.1 [2,3].
Simulation Scheme.

To investigate the device’s flow characteristics, the CFD numerical simulation models of the injection device with different structural and controlling parameters were built and related bench tests of the gas fuel engine equipped with the injection system were completed.
To comprehensively optimize the development accuracy, period and cost, both the methods of bench test and CFD simulation were adopted to confirm the flow rate characteristics.
As shown in Figure 3 and Figure 4, the test platform of the flow rate characteristics and simulation grid were built.
After massive numecrical simulation, the final flow formula was confirmed as G=0.05(Δt-Δt1) on the condition that the minimal injection width was double size of the transit time, which ,in practice, could be meet in the majority engine operating conditions as the gas fuel engine is applied as an heavy-power stationary powerplant.
(2) The simulation models and test bench of the injection device were established.

Gan and Riffat[5] investigated The performance of a glazed solar chimney for heat recovery in naturally-ventilated buildings was investigated using the CFD technique.
The probe was placed at 70-126 points at the chimney channel 1m above the chimney inlet.A computational fluid dynamic(CFD) [6] numerical simulation showed that at this position,the influence of disturbances from the chimney inlet and the reverse flow from the chimney outlet were small,and the airflow are essentially parallel to the chimney wall.The reverse flow was enlarged with the increase of the width of the chimney.Through moving the probe in the chimney cross-section 1m above the chimney inlet,the velocity of any position at the level surface were obtained.
Fig.5,Fig.6 and Fig.7 show the comparison of numerical simulation[6] and experimental airflow rate through the chimney width and 200,300 and400W/m2 heat input.
Comparison of experimental and numerical simulation airflow rate through numerica simulation airflow rate through chimey width with 200W/㎡heat input.
Fig.7 Comparison of experimental and Fig.8 Temperature distributions across chimney numerical simulation airflow rate through width at different height above the chimney inlet chimey width with 400W/㎡heat input.

Simulation and experiment results are also presented to illustrate performance of a specific designed thruster.
We hope to provide useful ideas for propulsion system designed special for M-ROV by some simulation and experiment results.
A further investigation through CFD simulation by COSMOSFloworksTM can be used to compare performance of different lines of contours.
All the initial parameters are shown in Table 2. 2) Detailed design of the propeller based on the results from the preliminary design, using the momentum theory, lifting line / surface theory or the surface element theory, and the general circulation model, the geometric model is determined, such as angle of the screw thread. 3) Final design for the propeller based on the detailed design of the propeller and the theory which is used in step two, the performance of the propeller is verified by CFD.

Mesh division is the basis for numerical simulation and it will directly affect the accuracy of numerical computation.
The simulation result of lift characteristics of airfoils NACA 4412 with or without modification is shown in Fig. 2.
Lift coefficient of airfoils with or without modification Angle of attack α/° Lift coefficient Cl Airfoil without modification Airfoil with simple Gurney flap Airfoil with remodeled Gurney flap Airfoil tested in NREL The simulation result of variation of drag coefficient with angle of attack of airfoils NACA 4412 with or without modification is depicted in Fig. 3.
Conclusions By using common software Fluent for CFD, numerical simulation is investigated in connection with the airfoil NACA 4412 and its modification.
The numerical simulation of aerodynamic performance of the airfoils is conducted with common software Fluent for CFD and its investigation method and result may be taken as an effective reference for the process of aerodynamic design of airfoils that suitable for wind turbines.

In recent years, with the development of computer and mathematics technology, works are concentrated on CFD simulation[9].The computational methodology allowed a clear capturing of the coherent structures of the flow field and it is helpful in understanding of complicated phenomenon.
Compared with CFD simulation, one-dimensional theory is easier to establish the relationship between pressure with target value and related parameters and to see through the appearance to perceive the essence.