Search results

The speed coefficient method based nuclear main pump design and CFD analysis Yan Liu1,a, Qiang Wang1,a, Peng-fei Zhao2,b 1School of Energy and Power Engineering, Dalian University of Technology, Dalian, China 2School of Naval Architecture Engineering, Dalian University of Technology, Dalian, China aandysnowqiang@sina.com, bzpfff@hotmail.com Keywords:nuclear main pump; spead coefficient; numerical simulation; impeller; leakage Abstract.Nuclear main pumps are one of the most important devices in nuclear plants.
Meanwhile numerical simulations are carried out to examine performances of the designed pump.
Meanwhile numerical studies based on computational fluid dynamics (CFD) technology are carried out to examine performances of the designed pump.
Numerical method To examine whether performances of the designed nuclear main pump meet demands or specifications, numerical simulations of water flow in the pump are carried out.
After repeated modification and numerical simulations, a relatively excellent hydraulic model is obtained.

At present, the major techniques to study the critical velocity are experiment and Computational Fluid Dynamics(CFD).
They used propane gas as the fuel and carried out a series of experimental tests and CFD simulations to five small-scale model tunnels having different cross-sectional geometry.
Numerical Simulation of Critical Velocity Using FDS Geometry and Initial Conditions of the Numerical Simulation.
The simulation time was set to be 240s.
Fig.2 Simulation results when fire heat release rate is 5MW Values of Dimensionless Critical Velocity Predicted by FDS Simulations and Calculated by Wu’s Model.

Simulation and Comparative Analysis on Environmental Control in Subway Liuming1, a, Zhang Baogang1, b, Wen Liu3, Huang Zhongzhi2 1 School of architecture and fine art, Dalian University of Technology, Dalian, China 2 Faculty of infrastructure engineering, Dalian University of Technology, Dalian, China 3 Municipal and environmental engineering college, Shenyang jianzhu University, Shenyang ,China aemail：liumingyitj@163.com bemail: Zhangbaogangtj@163.com, Keywords: Subway station; Thermal environment;Ventilation;Numerical simulation;Energy saving.
By using the CFD software, this paper takes an island platform with double-layer of Shenyang as the object to simulate the thermal environment of platform screen door and ventilation in the open system, then detailed analysis on the variation of the temperature field, airflow velocity field in the typical position.
And in view of the average temperature of the hottest month can not reach the standard of the conditions of the air conditioning in summer, so the ventilation system is adapted. this paper takes an island platform with double-layer of Shenyang as the object to simulate the thermal environment of platform screen door and ventilation in the open system by using the CFD software,,then detailed analysis on the thermal environment in the typical position.
Fig.3b Temperature field at 25 m from the train arriving area （planB） Fig. 3a Temperature field at 25 m from The train arriving area （plan A） The comparison simulation results of the temperature at 50m from the train arriving area passing through stairs is shown in Figure 4 .
At the same time,from the former chapter of the hottest month of the numerical simulation can be seen that the use of the open system can also satisfy the requirements of the subway specification，then an open systems can be acceptable in Shenyang area .

Keywords: biodiesel, microalgae, spiral bubble column reactor design, CFD analysis.
Numerical simulation Using commercial software CFX-14.0, 3-dimensional simulation is carried out in both the cylindrical bubble column reactor and spiral path followed bubble column reactor.
The transient simulation is performed with time step of 100×0.005, 100×0.1, 100×0.25, 53×0.50, 40×1 and 24×2.
CONCLUSION: Three-dimensional simulations of gas–liquid flow both in the bubble column reactor and spiral path column reactor have been carried out using the Euler–Euler approach.
[3] Ekambara K., Dhotre M.T., 2010, “CFD simulation of bubble column”, Nuclear Engineering and Design, 240(5): 963–969

CFD technology is used for simulation to obtain the airflow organization of the garage [1].
There are 8 induced fans with jet Angle of 15 °in this simulation [2].
In order to simulate the spatial distribution of the co released in the space of garage, the volume source is used in the CFD model to send out co, 12 pollution sources are uniform distributed on the driveway, there size is 0.5 m x 0.5 m x 0.2 m.
Numerical simulation research of no duct induction ventilation system in underground garage[D].
Numerical simulation of contaminant concentration in the underground garage.

Overall pressure drop of pleated aerosol filters The pressure drop of pleated air filters could be expressed as: (5) (6) Since The pleat angle in equation (6) could be expressed as ： Therefore: (7) Where, is permeability of filtration medium,; is tilt angle of filtration medium, is face flow velocity, PRESSURE DROP SIMULATION IN PLEATED FILTRATION MEDIUM Fluid field flow was simulation calculated by CFD software package in this paper.
In order to save computer resources, from the 80 pleats to select the four parts of them to conduct simulation.
Comparison of simulation results and experimental results was shown in table 1.The results of the simulation were different from the results of literature [3], but the simulation results were relatively close to results of experimental tests, it indicating that the simulation method of this paper was acceptable.
The simulation results of RSM turbulence model were in agreement with results of experimental test. 4.
Minimization of Resistance in Pleated-Media Air Filter Designs: Empirical and CFD Approaches.

The numerical simulation of the flow field in the micro-pressure inner loop reactor LIU Jiang-chuan1, a, YIN Zhi-gang1,b and JI Wei1,c 1School of Water Resources and Environmental Engineering, Changchun Institute of Technology, Changchun 130012, China aLiujiangchuan@yeah.net, bYinzhigang1972@163.com, cJiwei2012gc@163.com Keywords: the micro-pressure inner loop reactor, numerical simulation, mixture model Abstract.
The continuity equation: The Momentum equation is got though the summation of all respective phase momentum equation, it can be represented as the following: The relative speed is defined as the second phase: The relationship between the relative speeds and the drift velocity can be represented by the following formula: The equation of volume fraction: Numerical Simulation The micro-pressure inner loop reactor which is used in this model is shown as the figure 3, The length of the container is 80 cm, The height of the container is 60 cm, The width which is located at the top of the right side of the tube is 8 cm, and the height is 30 cm, it is connected with the atmosphere.
The Simulation Results and Discussion By calculating, we can get the velocity distribution field; trace the whole calculation domain and the volume fraction of air, the calculation results are shown in the figure 4 to figure 7. (1)The figure 4 is a velocity vector diagram of the hybrid model, the boundary of the contact with the atmospheric outlets meets the reality, because the gas which is squeezed out constantly can cause the velocity of gas-liquid mixing, and the velocity vector is Sometimes positive, sometimes the reverse.
Numerical Simulation and Experimental Study on Micro-Pressure Internal Circulation Reactor, J.
Edi.), 14(4). 11-14(2013) (In Chinese) [7] XU W, YU G, XUE C H, etal, Biochemical Changes Associated with Fast Fermentation of Squid Processing By-Products for Low Salt Fish Sauce, Food Chemistry, 107(4).1597-1604(2008) (In Chinese) [8] XIAO Hao-fei, ZHOU Mei-hua, CFD Simulation of Gas-Liquid Flow in Aeration Tank, Journal of Anhui Agri.

CFD Analysis of the EGR Cooler’s Heat Transfer Performance Zhi’en Liu 1, a, Yu Xu 1, b Wuhan University of Technology School of Automobile, Wuhan, China 430070; a lzen@whut.edu.cn, b smile4xy@sina.com Keywords: EGR cooler; Heat-flux coupling; temperature field; Abstract.
A CFD simulation of the performance of an EGR cooler was carried out.
This model based on decomposition methods was applied to the temperature field simulation under different EGR cooler rate and the simulation results were in good agreement with the experimental results.
Pic.7 Simulation result of the EGR gas-outlet part.
We got the average temperature of the outlet through simulation.

While CFD technology can make up for the deficiencies of experimental researches and provide directional guidance for the experiment .
In 1994 the turbomachinery committee of the Inter-national Gas Turbine Institute (IGTI ) have them used blind topic test evaluates the accuracy and reliability of the CFD program.
The simulations for high density and low density grids form based on R37 compressor rotor were performed.The result of simulations was compared with the related experimental data in order to study turbulence model influence on grid without dependence requirements.
Turbulence model Numerical simulation method based on the Reynolds average navier-stokes equations (RANS) has been widely used at present.
Rotor37-Blind Test Case, ASME: CFD Code Assess

Next, it presents the development of CFD-based motion simulator for guidance and control of PLATYPUS[4].
We have developed a CFD-based motion simulator for guidance and control of PLATYPUS.
Point to Point (PTP) Control Simulation using Fuzzy Control Algorithm.
We analyzed fluid-structure interaction using FEM program and CFD program iteratively at each step.
Fukui: Motion Simulation of an Underwater Vehicle with Mechanical Pectoral Fins Using a CFD-based Motion Simulator, Int.