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Numerical Simulation on South American Coal Reburning in a Pulverized Coal Combustor Zifang Wang1, Jianli Liu2, Liansheng Liu1, Bing Xia1, Jinxiang Wu1, Enyu Wang1, Xiang Gou1, a 1School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, China 2Bohai oil water and power service company, Donggu Oil New Village, Binhai New Area, Tianjin 300452, China aCorresponding author email: gouxiang@sina.com Keywords: simulation; NOx; South American coal; reburning Abstract.
In this paper, CFD software has been used to simulate the reburning process of South American coal(SAm) so as to study the effect of the reburning on the combustion in the furnace and NOx reduction.
Mathematical model CFD software for calculating the three-dimensional turbulent flow is used in this paper.
Carla, Reburning and burnout simulations of natural gas for heavy oil combustion, Fuel. 83 (2004) 109-121

The fluid domain model of a new oil-air distributor in oil-air lubrication system is built and the phase distribution of oil and air two-phase flow on distribution interfaces is simulated based on the CFD model in Fluent, the mass flow rate of oil and air are collected from three different cross sections when the structures of fluid guidance slot are designed as a plane, sphere and cone shape respectively, then the influence of oil-air guidance slot structure on the performance of distributor is analyzed in the oil-air lubrication system in this paper.
The working principle and simulation model of oil-air distributor The improved oil-air distributor structure is shown in Fig. 1.
Results and discussion In simulation we set that, air density is 1.225and viscosity is ; oil density is 890and viscosity is , in the turbulence model, set ，，，，，.
Conclusion (1) CFD simulation models of the improved oil-air distributor is built, the oil and air distributions of three different oil-air distributors whose oil-air guidance slot are designed as a plane, sphere, and cone have been simulated respectively
Structure Design and Performance Simulation of the Oil-air Distributor[D].

The pressure difference under different airflow velocity between two pressure openings set up at fuze inlet tube throat and expansion section was obtained by CFD simulation.
Through the simulation and analysis on ballistic characteristics and fluid pressure characteristics , the time characteristics of pressure difference of the pressure openings were summarized.
Results and discussion Building of numerical simulation model.Some radio proximity fuze was introduced as the studied object.
Fig. 3 External trajectory and projectile velocity curves The relation of shock wave producing position and inlet airflow velocity.The simulation was made utilizing the foregoing numerical simulation model of inlet channel in the range of 0.1M-1.6M of inlet airflow velocity.
The simulation results showed that the time of the pressure difference disappearance was in the range of 1.60-11.19s at different projectile velocity.

Abstract: In order to conduct lubricating characteristic analysis on automobile continuously variable transmission, this paper divides overall model of transmission on the basis of the idea of blocking simulation.
Through the above definitions, the generated oil gathering CFD model of oil gathering are shown as Figure 6.
Research on Flow Field Simulation for Lubrication System and Effect Evaluation on a 7-Speed Dual Clutch Transmission[A].
[6] Xu Xiang, Bi Xiaoping, Flowing Simulation of Lubrication System for Automotive Arranger[J], Lubrication and Seal, 2006,(2):17-19
[7] Xu Xiang, Bi Xiaoping, Heat Transfer Simulation Model of Transmission Case for Automotive Toothed Gear Drive[J], Mechanical Drive, 2003,27(5):1-4

The ways to study the forces of tube in process of sinking mainly take means of test and numerical simulation.
Scholars have done the appropriate research on such problems, Zan Dexin[5] had created the numerical simulation of the floating and sinking of tube, and analysed the theory on tube segment sinking.
The numerical model simulate the process of tube sinking, which is relied on the Guangzhou Zhoutouzui immersed tube tunnel, based on RNG k-ε turbulence model, used the Computational Fluid Dynamic (CFD) method.
Numerical simulation of immersed tube sinking The numerical model The sinking speed of tube segment is 0.5m/min, the distance from the water surface to trench bottom is 9.56m.
Conclusions It have simulated the process of tube of immersed tube tunnel sinking using CFD method, obtained the following conclusions.

By comparison with indicator diagram, simulation results were consistent with the test results using pure diesel and 5%(volume of n-butanol) n-butanol/diesel blends.
Diesel engine combustion and spray numerical simulation has become a kind of effective means for researching and designing diesel engine [3].
Fig. 2 and Fig. 3 are indicator diagrams of experiment and simulation results respectively using pure diesel and 5%(volume of n-butanol) n-butanol/diesel fuel mixture.
In general, the errors are within 5%.So the calculation model are reasonable and correct, which can be used for combustion simulation of fuel mixture.
Annual meeting papers of AVL,(2010) [5] Kong S C，Reitz R D: Application of detailed chemistry and CFD for predicting direct injection HCCI engine combustion and emissions[J]．Proceedings of The Combustion Institute.(2002)29:663-669 [6] Lehtiniemi H, Fabian M, Balthasar M．et a1: Modelling diesel ensine combustion with detailed chemistry using a progress variable approach[R].2005-01-3855.Detroit:SAE.(2005) [7] AVL, CFD-Solver_v2010_04_ICE-Physics-Chemistry, (2010) [8] D.C.

All these computational process is carried on by CFD commercial code FLUENT 6.3.
Validation of Simulation Results Fig. 6.
Fig. 6 shows that the results of 3D numerical simulation and the experiment are closer, however 2D numerical simulation results are still in the range which is allowed in engineering and 2D simulation also has economical cost.
Summary 2D and 3D numerical simulation by commercial CFD code FLUENT 6.3 of different inlet velocity is performed and resistant characteristic experiment is carried out. 2D and 3D numerical simulation results agree well with data of resistant characteristic experiment and multipoint pressure measurement.
The Numerical Simulation of Marine Moisture Separators.

With the development of the computer technology, fluid mechanics and finite element theory, computational fluid dynamics (CFD) has been applied to the internal flow field and flow performance simulation of the heart pumps.
Basic Parameters Because blood is not pure Newtonian fluid, if use the non-Newtonian fluid to simulation, can make the simulation process to be very complicated.
CFD Simulation Results Analysis Both schemes converges around 160 steps, and the corresponding physical quantities no longer change.
Performance Characterization and CFD Analysis of an Axial Blood Pump [J].
Effect of Rotor Blade Angle and Clearance on Blood Flow[C]//The 7th International Conference on CFD in the Minerals and Process Industries, December 9-11, 2009, Melbourne, Australia, 2009:1～6

Germain and Baier. [19] Performed numerical simulations on turbine blade channels to identify the flow structure and quantity the secondary flows that are essential for the investigation of losses in a turbine blade channel.
Alameldin et al. [20], performed a CFD Analysis to study the increase in total losses of a transonic turbine blade subjected to film cooling.
The transport equation is additional term utilize to simulates a non-reacting gas mixture when this gases jet in to a cross-flow at different density; the simulations were processed using the CFX software from ANSYS, Inc.
The numerical simulation of the coolant flow through hole system is carried out using the CFD package Ansys CFX coupled with the optimization technique to maximize the film cooling effectiveness.
[16] Lakehal, D., Near-Wall Modeling of Turbulent Convective Heat Transport in Film Cooling of Turbine Blades with the Aid of Direct Numerical Simulation Data.

Structure Design of and Numerical Simulation on an Annular Reverse Circulation Drill Bit Jinsong Wang a, Pinlu Cao b,*, Kun Yin c College of Construction Engineering, Jilin University, Changchun 130026, China awangjs12@mails.jlu.edu.cn, bjluplc@163.com, cjluyink@163.com Keywords: Reverse circulation drilling; Normal inner nozzle drilling bit; Annular reverse circulation drilling bit.
In this paper, the computational fluid dynamics (CFD) code, FLUENT, is employed to simulate the flow phenomena of reverse circulation drill bit.
Numerical simulation results show that the values of negative pressure of new type annular reverse circulation drill bit which formed in the center channel and the bottom of hole were larger than those of the normal bit.
(a)Normal drilling bit (b) Annular drilling bit Fig.6 The mass flow rate of the boundaries Conclusion We use the computational fluid dynamics (CFD) code, FLUENT to simulate the flow phenomena of reverse circulation drill bits.