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After presenting the mathematical description of dynamic fluid for 2-phase flow, numerical simulations are launched to reveal the characteristics of droplet generation and key factors are discussed.
In this paper, the following will be presented: mathematical modeling of 2-phase flow for jet-dispensing, numerical simulations on droplet generation with finite volume solver, experiments and discussions on its feasibility for ink marking of defective dies.
With compensated pressure changing from 10 to 30 kPa, the radii of ink droplets falls on the interval of [0.247, 0.448] (mm) and corresponding jetting velocities are on [0.729, 1.213] (m/s) , which coincide with simulation results in Table 1.
Compensating pressure facilitates the pitch-off of droplet, as observed in CFD simulation, the breakup of droplets shows good response with the pressure descent (or negative edge) on nozzle inlet, which is defined as a periodical pressure boundary condition.
[8] Yong Zhao, Hsianghui Tan and Baili Zhang: A high-resolution characteristics based implicit dual time-stepping VOF method for free surface flow simulation on unstructured grids.

The computer simulation of the mixing behavior was performed with a commercial package, named Ansys CFD.
Physical properties of the fluids Fluid Dye Color Density(Kg/m3) Viscosity(N．s/m2) Diffusion(Kg/m) Water Red 997 1.002x10-3 2x10-6 Acetone Blue 780 0.324x10-3 2.06x10-5 The simulation results show that the best mixing was obtained in mixer A, so the simulation and experimental results for the mixing status in mixer A were compared.
Fig. 5(a) and 5(b) show full-field mixing images obtained from the numerical simulations and experiments, respectively.
As can be seen, the overall mixing efficiency from the numerical simulation tends to agree with the experimental measurements.
Mixer A Re = 1 Re = 10 Mixer A Re = 1 Re = 10 (a) Images from numerical simulations sec.1 sec.2 sec.3 outlet sec.1 sec.2 sec.3 outlet (b) Images from experiments sec.1 sec.2 sec.3 outlet sec.1 sec.2 sec.3 outlet Fig. 5 Full-field mixing images for (a) numerical simulations and (b) experiments.

LTD, Chengdu, Sichuan, 610031, China a wastewater_2000@163.com b 13880804985@qq.com c tey_lsp@163.com Keywords: Heat release rate, CRH Passenger rail car, Window glass, Ignition temperature, Fire numerical simulation.
To some extent, the fire spread speed and scale mainly depend on the HRR, which is an important parameter for the fire protection and control technology, especially such as the fire risk assessment and fire numerical simulation.
In the following, the experiment and numerical simulation methods are combined to research the influence of window glass ignition temperature on the HRR of CRH passenger rail car.
Migoya [7] showed a method to determinate the HRR using sensors that can be installed inside an operational road tunnels by comparison with CFD calculation.
Influence Analysis of Window Glass Ignition Temperature on the HRR According to the simulation results and figure 4, 5, when the window glass ignition temperature is 470℃, 525℃, 580℃, the window is not broken during the whole fire process, but from beginning to end closed to prevent the outer fresh air into the passenger rail car, so the peak HRR only can reach 18.4MW, and then begins to decline dramatically due to the oxygen deficit.

Numerical simulation results give a better approximation to practical reproduction, successful prediction of weld shape, weld defects and peak temperature.
In order to study the microstructure changes associated with FSW, thermal modeling is a central part of FSW process simulation [2-3].
Despite the complex flow pattern, extensive research has been carried out and focused on thermal modeling of FSW, which is considered the basis of all the models of the process i.e. mechanical, computational fluid dynamics (CFD) and other coupling models.
Numerical simulations have been carried out to reveal the effect of process parameters on the temperature fields.
Numerical simulation results give a better approximation to practical reproduction, successful prediction of weld shape, weld defects and peak temperature.

Numerical simulation [3] was conducted with the ProCAST TM software from ESI.
Physical properties of AA5052 used in the simulation.
Mathematical Simulation Tool - Part III - New Simulation Package Results The previous model was imported in the new platform, allowing much smaller computation time and giving us the opportunity to verify the influence of turbulence.
The CFD model solves differential equations describing the conservation of mass, momentum and energy in order to evaluate the velocity, pressure and temperature fields.
Simulations were carried out for steady state conditions and an inlet velocity of 240mm/s.

When simulation results are qualitatively compared to Fig. 3, the similarity is obvious.
Simulations using three dimensions are already underway.
The question is again what we want from the simulations.
For a long time it has been possible to make comparisons between different nozzle designs using either water models or CFD modelling without solidification.
Nieminen: Real-Time Simulation of Heat Transfer in Continuous Casting.

This paper presents the analysis of the effect of smoke exhaust and hot gases from an atrium type building using techniques for numerical simulation of a fire situation.
This approach, specific to two-zone fire models instead of CFD models, can provide a quick overview for fire protection engineers.

The numerical procedures employed in the simulations are depicted in Section 3.
In the simulations of this study, two different phases are considered: air and water.
The time processing of each simulation was approximately 3.2 × 104 s (9 h).
V European Conference on Computational Fluid Dynamics, ECCOMAS CFD 2010, Lisbon, 2010
Horko, CFD Optimization of an oscillating water column energy converter, MSc.

Examples of Aerodynamic Heating Prediction CFD Model and Grids System.
Fig.4 The girds system for analysis Fig.5 The thermal stress curve of stagnation point cell depends on time Fig.6 The contours of temperature and thermal stress at symmetry when heated 40 seconds Fig.7 The deformation of structure when heated 40 seconds Analysis for Simulation Results.
Numerical Simulation for Aerodynamic Heating and Opposing Jet Thermal Protection.
Numerical simulation of an improved cone-derived waverider Vol. 31(6)(2010), p.725~730P.

The CFD software Fluent14.0 was utilized as a solver.
Fig. 2 Steady-state simulation value of Fig. 3 Steady-state simulation value of the spatial concentration field distribution spatial temperature field distribution Fig. 4 Steady-state simulation value of space Fig.5 Steady-state simulation values of velocity vector on the condition of boiling space streamline evaporation of fuel The data of thermocouple and concentration sensor were real-time acquired and displayed on computer and were refreshed once every minute.
The comparison between experimental values and simulation results are shown in from Fig.6 to Fig.9.
It can be seen from Fig.6 to Fig.9, the simulation value of space concentration distribution in the 0.1m is smaller than the experimental measured value.
While in 0.2m and 0.3m, simulation value is larger than the experimental measured value in the first 60 seconds, and then simulation value is smaller than the measured value, and the deviation between them becomes larger with time.