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Study of flow characteristics of oil and water in the process of stirring Zongrui Hao1, a, Juan Xu1, b, Haiyan Bie2, c Zhonghai Zhou1 1 Institute of Oceanographic Instrument of Shandong Academy of Science, Qingdao, 266001, China 2 College of Chemistry and Chemical Engineering of Ocean University of China, Qingdao, 266100, China ahaozr001@sina.com, bxujuan101066@163.com, csalany001@163.com Keywords: Stirring, Multiphase flow, Flow pattern, Numerical simulation Abstract.
Numerical simulation results and analysis As the density of oil is lower than water, the influence of oil-water is the combined action of the buoyancy and the shearing force in the stirring process.
CFD simulation of liquid-phase mixing in soild-liquid stirred reactor, Computers and Chemieal Engineering.

Adopting the RSM (Reynolds stress model) to conduct numerical simulation on gas phase flow field in bypass cyclone separators with two kinds of inlet structure, meanwhile, interphase coupling discrete model DPM is used to simulate the trace of particles in bypass cyclone separator.
In the recent years, CFD technology is used more and more in computing the gas-solid field [1] in the separator as the technology develops fast.
Simulation Result Analysis.
Fig.4 demonstrates the change of downside flow along the axis in the separating part at the end of the chimney by numerical simulation and computation.
In numerical simulation, the inlet of separator B is divided into three different regions, the region near the wall, the region in the center part and the region far away from the wall.

Name Section view Axonometric drawing Description Modal a Planar dimensions: 75m*75m Side interfaces on the windward side and the leeward side: Vertical Window height: 1.2 m Sash: center-pivoted type Modal b Planar dimensions: 75m*75m Side interfaces on the windward side and the leeward side: Tilting outward by 60° Window mode: The same as model a Model c Planar dimensions: 75m*75m Side interfaces on the windward side and the leeward side: Tilting inward by 60° Window mode: The same as model a Note: On the section views, air flows from left to right. 1.2 Determination of the air flow equation In the simulation based on Fluent software in this paper, the standard k-ε two-equation model, i.e. a semi-empirical model including a transfer equation about turbulent kinetic energy and another about diffusion rate, was used.
Table 5 Average Wind Velocities in the Seating Area in Different Models Model Average wind velocity in the gallery seat area on the windward side (m\s) Average wind velocity in the stall area on the windward side (m\s) Average wind velocity in the stall area on the leeward side (m\s) Average wind velocity in the stall area on the windward side (m\s) Model a 0.142 0.415 0.075 0.049 Model b 0.234 0.709 0.197 0.062 Model c 0.096 0.618 0.113 0.075 In the nephograms and vector diagrams about wind velocity simulation, the warmer the colors, the larger the corresponding wind velocities will be; the cooler the colors, the smaller the corresponding wind velocities will be.
Computational Fluid Dynamics Analysis: Theory and Application of CFD Software [M].
CFD and Architectural Environment Design [M].
A CFD-based test method for control of indoor environment and space ventilation [J].

Numerical Simulation of the cooling effect by air conditioner and spraying in high-temperature working face LIU Guan-nan a, GAO Feng b, JI Ming c, LIU Xing-guang d College of Science, China University of Mining &Technology, Xuzhou, 221000,China a guannanliu@126.coml, b ssnn521@126.com, c iflove0922@126.com, d youxiang_liu@126.com Keywords: stochastic model; working face; temperature field; SIMPLE algorithm.
A multicomponent turbulent model of the airflow in working face was modeled.And the simulation result is compared with the measured temperature.The temperature of the airflow along the transportation channel of working face goes up,and the gradient of the temperature curve is flat.Then the low-temperature droplets are simulated by stochastic separated flow model.The interaction between grains and fluid are simulated by adding source terms in conservation equations.The temperature curves of the airflow under different cooling schemes are investigated.If the air conditioner is in front of the nozzles,the temperature of the air near the inlet is low and uniform,and the cooling effect of the outlet is obvious.
The simulation result and the measured temperature in the transportation channel From Fig.1 shows that the simulation result well fits the measured data .The temperature of the airflow goes up along the channel,and the temperature difference between the inlet and the outlet is about 1℃.The model could be used for analyzing the distribution of the temperature in mine.
[5] Zhou Lixing.Simulation of turbulent two-phase flow and combustion.Beijing:Tsinghua university press,(1991) [6] Patankar S.V.Sparrow E.M.and Inanovic M.Heat Mass Transfer Vol.24.(1978) [7] Berlemont A,Grancher M S,Gouesbet G.
[9] Wang Fujun.Analysis of computational fluid dynamics-theory and application of CFD softwares..Beijing:Tsinghua university press,(1991)

Simulation results demonstrate that the composite control system has good performance in tracking AOA and acceleration command by respective deflection in cruise.
The position and efficiency of wings are carefully optimized by CFD computation.
The control system structure of hypersonic vehicle Simulations of Composite Control System Assuming the hypersonic vehicle flight height , the velocity (), the trim angle of attack ,and the command of the velocity (), and while the scramjet engine is power on, the command of the normal maneuver acceleration.
The simulations of the composite control system are shown as follows.
Simulation results show that the composite control system can separately trail the command of velocity, AOA and normal maneuver acceleration accurately, and the normal maneuver acceleration doesn’t affect the AOA in cruise.

Meanwhile, in order to verify reliability of the thermal gas mass flow meter in the system, we adopted CFD method to simulate the EGR cooler by using empirical parameters, and collected several related sensor parameters of the EGR cooler in the condition that the inlet temperature was constantly at 368K while the coolant had 4 kinds of degrees.
Temperature and pressure cloud chart of the EGR cooler flow field Table2 is the experimental results of EGR cooler; table3 is the simulation results of EGR cooler.
Simulation results of the EGR cooler (K) (L/min) (K) (bar) (kg/h) (bar) (kPa) (kPa) (K) 368 20 836 2.1 91 1.6 20 10 472 368 25 836 2.1 90 1.6 20 14 468 368 30 836 2.1 90 1.6 20 19 463 368 35 836 2.1 90 1.6 20 28 461 According to Table 2 and Table3, the critical data EGR gas outlet temperature, the overall heat transfer coefficient and coolant flow curve are plotted into figure 5.
Compared to simulation values, the gas outlet temperature of the experimental value is about 1.17% lower on average; and the heat transfer coefficient is 3.1% larger on average.
Meanwhile, in order to verify reliability of the thermal gas mass flow meter in the system, we adopted CFD method to simulate the EGR cooler using empirical parameters, and collected several related sensor parameters of the EGR cooler in the condition that the inlet temperature is constantly 368K while the coolant had 4 kinds of degrees.

Influence of Piston Initial State on HCCI Combustion in Micro Free-piston Engine Using Experiment Images and CFD Analysis Jin BAI Qian WANG Zhixia HE Penggang ZHANG School of Energy and Power Engineering, Jiangsu University, Zhenjiang 212013, China perking1984@yahoo.cn Keywords: free piston, micro engine, HCCI, visualization, numerical simulation Abstract：The visualization experimental setup of micro free-piston engine has been built, the process of single shot compression combustion in micro combustion chamber has been observed by the high-speed digital camera; Based on the propane combustion kinetics, the numerical calculation method for combustion process coupling with the free-piston movement was put forward, through editing the dynamic mesh subroutine in STAR-CD, the process of homogeneous charge compression ignition (HCCI) in the micro chamber was studied; The influence of piston initial state on HCCI combustion process was analyzed , indicating that the piston mass
In this paper, combined with the visualization experiment and numerical simulation method, the influence of piston mass and initial velocity on the process of HCCI in micro free piston engine was analyzed quantitatively.
Fig.2 Experimental setup Fig.3 The compression combustion process under different gap conditions Model validation.As the experiment work is developing gradually, the numerical simulation is also developing at the same time, validation of experiment and simulation results is necessary and meaningful.
Fig.5 makes good comparison of experimental and numerical simulation results, and more variable parameter simulation could be calculated.
Fig.4 Images from experiment Fig.5 A comparison of piston position data Results and discussion Simulation results under different piston mass.Fig. 6(a) to 6(c) show the simulation results of HCCI compression combustion under different piston mass conditions, the micro combustion chamber diameter is 3mm, the free-piston initial velocity is 30m/s, the equivalence ratio is 0.5, the initial temperature is 300K, the initial pressure is 0.1Mpa, and the piston mass are respectively 0.5g,1g,1.5g and 2g.

Simulation of Initial Ribbon Formation during Planar Flow Melt Spinning Process M.
Fig. 1 Schematic of PFMS process Fig. 2 Air domain – A 3D model used in the simulation.
A 3D model is developed to simulate the ribbon formation during planar flow melt spinning process using commercial CFD software.
Temperature dependent viscosity and constant surface tension are considered for the molten metal during simulation.
Hence, simulations were carried out up to 1.2 ms with a time step of 1e-5.

The author applied computational fluid dynamics (CFD) technology to numerically simulate the erosion law of the internal drill pipe in different drilling fluid displacement, different mechanical drilling speed and different cutting particle size.
CFD Model and Boundary Conditions.
The computational fluid dynamics (CFD) model established in this paper is shown in Fig. 1.
Fig. 2 Schematic diagram of meshing Internal Drill Pipe Simulation Results for Drilling Fluid Carrying Rock Erosion The influence of different factors on the erosion law of the inner drill pipe was analyzed by changing the initial conditions.
Numerical simulation of liquid-solid erosion in sudden expansion and contraction tube (in Chinese).

For the purpose of utilizing of wind energy around urban buildings, an technique to gather natural wind energy by artificial energy-gathering tunnel is investigated using numerical simulation method.
An optimized configuration of the tunnel is obtained by numerical simulation and analysis, in which the accelerating ratio is about 2.02 and the wind power density increases about 7.24 times.
Based on the above considerations, four cases (see table 1) are analyzed one by one using numerical simulation method.
The air density is set as in all the simulations in this paper.
Computational fluid dynamics-CFD software principles and applications.