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Investigation of a Micromixer for the MTPV System CHENG Guanggui 1,a, DING Jianning 1,2,b and LING Zhiyong 1,c 1Center of Micro/ Nano Science and Technology, Jiangsu University, Zhenjiang Jiangsu 212013, China 2Changzhou University, Changzhou Jiangsu 213016, China aggcheng@ujs.edu.cn, bdingjn@ujs.edu.cn, czhyling@ ujs.edu.cn Keywords: micromixer, CFD simulation, MTPV system Abstract.
The optimal structure parameters were investigated by computational fluent dynamical software (CFD)，during the simulation, three main parameters n,τ and δ were introduced to studied on the influence of the mixing intensity.
As we all know that the optimal mixing rate of H2 and O2 is 2:1, so we use these mass flows as simulation parameters.
We observe the situations of τ=0, 0.25, 0.5 and 0.75 through the simulation process.
At last，a micromixer was fabricated with optimal parameters based on the simulation results.

We also performed numerical experiments using commercial CFD software FLUENT 6.3 based on conditions of experiment.
We also performed numerical experiments using commercial CFD software FLUENT 6.3 under the experimental conditions.
Table 1 Experimental data of air flow rate and the weight of outflow water No. 1 2 3 4 5 6 7 8 Air flow rate (m3/h) 0.40 0.44 0.48 0.52 0.56 0.60 0.64 0.68 Water weight (kg) 12.2 15.4 18.2 21.9 25.0 29.3 32.5 37.2 CFD Simulation The artificial upwelling seawater depth was about 200m, so further studies have to determine the upwelling efficiency under the condition that the length of the upwelling-pipe is about 200m.
Eight sets of simulation results based on the different inlet air flow rates (Table 1) were obtained.
Much more factors, such as the compressibility of air bubbles and the salinity of sea water, would be considered during the CFD simulation.

The paper presents the numerical analysis of erosive wear on the guide vanes of a Francis turbine using CFD code.
The flow mechanism of sandy water in the turbine was analyzed through numerical simulation of flow in the turbine in several different sand water concentrations.
Unsteady numerical simulations, based on the two-phase homogeneous model, are performed together with wall pressure measurements and flow visualizations.
OpenFOAM is an object-oriented C++ library of classes and routines of use for writing CFD codes.
It has a set of basic features similar to any commercial CFD solver, such as turbulence models and discretization schemes.

The aerodynamic characteristics of the spherical aircraft, including the lift and the anti-torque and the generated torque of the flow deflectors under the propeller’s down airflow, are studied in depth by means of CFD numerical simulation method.
Thirdly the aerodynamic characteristics of the aircraft was simulated and studied in CFD soft, and the results obtained through simulation were analyzed and compared with the theoretical values.
It was obvious that the results of the theoretical and simulated values was very approximate, which verified the accuracy of the CFD numerical calculation.
Conclusion Through the theoretical modeling and numerical calculation of the aircraft’s aerodynamic characteristics above, the following conclusions can be drawn: 1) The structure design of a single propeller spherical aircraft is reasonable. 2) There is a good consistency between CFD numerical simulation method and theoretical calculations, which indicates the reasonableness of the CFD numerical calculation method.
So the CFD method can be used to estimate the lift and torque of propellers, and to provide data to support the design and production of aircrafts. 3) The theoretical modeling of the spherical aircraft in this paper is correct.

Numerical simulation of indoor thermal environment of a double-skin facade office with different shutter angles Xin Zhan, Hua Yanga, Fengyun Jin Hebei University of Technology, Tianjin 300401, PR China aCorresponding email: y8h8@163.com Keywords: Double-skin façade, Shading devices, Office thermal performance, CFD Abstract.
Airflow and heat transfer simulation was conducted for a double-skin façade (DSF) system equipped with shading devices in the cavity, using computational fluid dynamics (CFD) with RNG turbulence model and PISO algorithm, for five conditions of slat angles (θ=0°, 30°, 45°, 60°, 90°).
modeling and simulation The model chooses an office that the size is 4m×4m×5.5m, and the width of cavity is 500mm.
A CFD approach is employed to model and simulate the airflow and heat transfer in the DSF system.
Results and discussions All the models are selecting the 13 o’clock as the simulation time so that it makes sure that there has enough solar radiation.

Part of work on CFD simulations by the high-lift system design team in Fudan university for large civil aircraft is presented.
The research on CFD simulation of the high-lift systems and some concepts and experience in three-dimensional geometry modeling are also presented, which are done on the self-developed platform of high-lift device aerodynamic calculation software and programs.
Application of Kriging method In Comparison of CFD and Wind Tunnel Data. 14th national CFD conference.
CFD V&V and Open Benchmark Database[J].
Numerical Simulation Of High Lift System Configuration[J].

The CFD method is developed to investigate the effect of cavity geometry on aerodynamic performance of hypersonic vehicle with a forward-facing cavity on the nose-tip.
The CFD results are compared with the experimental results and there is a good agreement between them.
The grid of simulation model on the symmetry plane and on the wall of the nose-tip is shown in Fig.2 and Fig.3 (validating example 2).
A big agreement is shown between simulation and experiment results in these figures.
Some errors come from the assumption of simulation model, counting error and experimental measurement.

Final CFD simulations were carried out at the optimized cell number.
The simulation could probably be further improved by using a finer grind around the MRF.
Table 3: Numerical and experimental hydrodynamic quantities of mixed-flow impeller at 600 rpm model axial-CFD (m3/s) radial-CFD (m3/s) Qr-CFD (m3/s) Torque-CFD (N.m) Torque-Experimental (N.m) Nq Np (CFD) RSM 1.001 0.036 0.965 0.008 0.011 0.58 1.00 Conclusion The flow characteristic of a mixed-flow impeller in a baffled vessel has been presented.
Experimental measurement and computational fluid dynamics simulation of mixing in a stirred tank: a review.
CFD modelling and mixing in stirred tanks.

Research on CFD of Fluidization of Biomass Waste Fast Pyrolysis Reactor Rui Li a, Liangjing Jingb and Mingming Hec College of Materials Science and Technology, Beijing Forest University, Beijing 100083, China aboxlr@126.com, bliangjing777@163.com Keywords: Pyrolysis; Fluidization; Simulation; Reactor.
The understanding of computational fluid dynamics (CFD) of its fluidized bed is necessary basis for particulate heat transfer and pyrolysis kinetics research.
Therefore, the CFD method and values of parameters used in this paper can apply to the calculation of fast pyrolysis fluidized bed reactor.
Fig.4 Simulation results on the pressure Fig.5 Experimental data on the pressure Simulation results under the cold state.
The simulation results of the pressure in the reactor are in good agreement with the simulation results and experiment data, and the resultant error is lower than 10%.

According to the simulation results from CFD, the node loads at the interface of pump wheel and the working fluid were obtained and the torque and axial force were predicated.
The pressure and velocity fields in a coupling can be obtained from a CFD simulation.
A further study was made by Yongquan Wang etc. in Ref.11, where the deformation model of wheel was exported to CFD again and the simulation result showed that the deformation of which has small influence on flow field .
CFD analysis.
Contours of results simulation.