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CFD simulation of magnetorheological fluid journal bearings[J].Simulation Modelling Practice and Theory, 2011,19(4):1035-1060

A numerical simulation is carried out to minimize the flow maldistribution inside the microchannel.
From the simulation results it was found that the mal-distribution is significantly affected by flow rate and shape of the header.
In the numerical simulation, it is identified that CFD is a suitable tool for predicting the flow distribution and for optimizing the design of the microchannel.
Shuaib, Numerical simulation of heat transfer in wavy microchannel heat sink, International Communications in Heat and Mass Transfer. 38 (2011) 63-68

Numerical Investigation of Effect Pilot Injection on Combustion Noise and Exhaust Emission of Diesel Engine Tiemin Xuan a, Zhixia Heb , Zhaochen Jiang and Yi Yan School of Energy and Power Engineering, Jiangsu University, Zhenjiang 212013, China axuantiemin@163.com, bzxhe@ujs.edu.cn Keywords: diesel engine, fuel injection strategy, combustion noise, exhaust emission, numerical simulation Abstract.
Because of the symmetrical location of the injector at the center of the combustion chamber, the CFD calculations were performed with the mesh of 45ºCA sector meshes.
Calculations begin at Intake Valve Closure (218.5ºCA) and end at Exhaust Valve Opening (483ºCA) .The final mesh consists of a hexahedral dominated mesh shown as Fig. 1 Table 1 Engine specifications Engine type 1015 diesel engine Bore×stroke 132mm×145mm Compression Ratio 17 Connection rod length 262mm Engine speed 2100r/min Number of nozzle holes 8 Nozzle hole diameter 0.23mm Start of injection 350ºCA Fuel injected 180mg/cycle Injection pressure 90MPa Fig.1 The mesh of combustion chamber Fig.2 The comparison of pressure between experiment and simulation Calculating models.
The rate of pressure rise, temperature in cylinder, and Soot emission got from simulation for different injection strategies are given in Fig.3, Fig.4, Fig.5 respectively.
[3] Weisheng Zhu: Simulation of the Influence of Pilot Injection and Post Injection on the Combustion and Emission of Diesel Engine [D]. 2009.12 [4] Hyun Kyu Suh, Investigations of multiple injection strategies for the improvement of combustion and exhaust emissions characteristics in a low compression ratio (CR) engine.

Therefore, in this paper XFOIL was used to design preliminary airfoil, and then CFD tools were used to optimize and validate the airfoil.
However, accurate derivate can only achieved from CFD or wind tunnel, which have the disadvantage of intensive-calculation, high-cost, long-cycle, and aren’t fit for using in general design.
Numerical simulation of laminar separation bubble over 2D airfoil at low Reynolds number.

CFD simulation of homogenization in large-scale crude oil storage tanks [J].
CFD calculations of gas leak dispersion and subsequent gas explosions: validation against ignited impinging hydrogen jet experiments [J].Journal of Hazardous Materials, 2010, 179 (1):84-94

Hou [8] carried out a numerical simulation on a swirling flow tundish with different turbulence models.
The simulation model setup is shown schematically in Fig.1.
In this study, the commercial code ANSYS FLUENT 13.0 is used with the ICEM CFD for the mesh generation.
Fig. 6 shows the trend lines of S and Xr in different simulation cases.
Bassam Dally from the University of Adelaide, for their patient and helpful instructions and advice on the CFD simulations.

To know that turbine, the paper introduces the flow passage character and hydraulic performance by the method of CFD.
And simulation result is listed on the third row in the table 1.
The simulation result is listed on the forth row in table 1.

. , Chang chun 130025, China; 2 State Key Lab. of Automotive Simulation and Control, Jilin Univ. , Chang Chun 130025, China a707193961@qq.com, blimingtiger@jlu.edu.cn, cxiaoye199046@126.com,d157178304@qq.com,e646358306@qq.com Key words: Numerical Simulation, Flow Distribution, Fitting Correlations Abstract：In this paper, the heat transfer rate of parallel flow heat exchanger was obtained in the condition of non-uniform flow distribution by 3D numerical simulation.
The concept of the second set of the tube was proposed by Anjun Jiao and Rui Zhang[7].The relation between S and Re in different forms of the tube bas been summarized.The uniformity of flow distribution has been improved by optimization of the forms.These researchs focused on the influence of structure changing.However, the non-uniform flow distribution on heat transfer efficiency was rarely involved.The correlation of the influence of non-uniform flow distribution on heat transfer efficiency was obtained by the comparative analysis of non-uniform flow distribution and heat transfer efficiency and regression calculation.The design consideration is accurately provided by the relation. 3D numerical simulation of the heat transfer rate of parallel flow heat exchanger Model and boundary conditions In this paper,two processes parallel flow heat exchanger has been researched.The first processes is made of 9 tubes,and the second is made of 12 tubes.Based on the CFD software for the flow of
the inside fluid of the heat exchanger ,condition on the heat transfer has been simulation analyzed by finite element method of mass conservation equation ,standard k - epsilon model,liquid R134a , 0.001003kg/（m·s）of inlet viscosity,1265kg/m3 of density,0.0093m3/s of the initial import flow,0.1m/s of flow velocity,pressure outlet and 190000Pa of gauge pressure.
The actual heat exchange capacity can be obtained by the 3D numerical simulation and the theory heat exchange capacity of parallel flow heat exchanger by 1D calculation .
Conclusion In this paper, the heat transfer rate of parallel flow heat exchanger was obtained in the condition of non-uniform flow distribution by 3D numerical simulation.The maximum theoretical heat transfer rate of parallel flow heat exchanger was obtained through 1D calculation.

Optimal Simulation on the variable load for an Ultra-supercritical Boiler Lingda ZENG 1, a, Zhongguang FU 1 and Hancai ZENG 2 1Key Laboratory of Condition Monitoring and Control for Power Plant Equipment (North China Electric Power University),Ministry of Education, Beijing 102206, China; 2State Key Laboratory of Coal Combustion (Huazhong University of Science and Technology),Wuhan 430074,China; alingda-zeng@chdoc.com.cn Keywords: ultra-supercritical boiler; combustion; variable load; optimization; numerical simulation Abstract.
In this paper, 1000MW Ultra-Supercritical Boiler is as a prototype, meanwhile using CFD software Fluent for simulating the ultra supercritical and the opposed firing Fired Boiler variable load operating condition process in order to grasp the burning combustion characteristics of the boiler under changing conditions and provide the guidance information for adjusting and optimizing the buring process.
Calculation methods and boundary conditions The object for numerical simulation is a 1000MW ultra-supercritical boiler which take the method of opposed firing supercritical boiler transformer parameters and Π-type layout.Design and check the coal mixed with the coal of Jibei Mine and Yan Mine.
Figure 1 Furnace structure and grid Simulation results and analysis simulation results and analysis Figure 2 different load is along the average temperature of the furnace high, oxygen amount, CO and CO2 and NOx density distribution.

Numerical simulation of the water transportation process in xylem is studied based on Ansys 12.0/fluent.
A 3-dimensional model for the flow field was then established, and the steady state flow was simulated with the computational fluid dynamics (CFD) software based on Navier-Stokes equations.
Simulation of 5 pits vessel element with different pits’ diameters.
Simulation of 10 pits vessel element.
Simulation of 20 pits vessel element.