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This paper focuses on the effects of helium injection on the cooling performance of glass fiber cooling unit in high-speed optical fiber manufacturing, and it will present the numerical investigations of glass fiber cooling process by using the flow and convective heat transfer modeling and CFD computations.
A multi-propose commercial CFD software, FLUENT 6.3, has been employed in solving the governing equations for continuity, momentum, and energy for the numerical simulations of flow and temperature fields for both cooling gas and fast moving glass fiber.
All the simulations used the block structured computational mesh and the total number of quadrilateral cells is approximately 125,000.
Note that the species transport of two gas components is also included in the simulations.
Due to large temperature variation, temperature dependence of thermal conductivity and viscosity for the cooling gas is also considered in the simulations.

Energy consumption of gas-fired infrared radiant and heat exchanger by convection heating is comparative analyzed, CFD software is used to simulate fields of the temperature and the predicted percentage of dissatisfied.
Their study focused on the difference between the simulation results and the results obtained by ASHARE method, it is concluded that the ASHARE method results are 21% higher than that of simulation [5].
CFD software is used to simulate the temperature and the PPD (predicted percentage of dissatisfied) field.
Radiant heating Fig.3 Steady state of the two different heating modes Based on heat load: The simulation results of the two heating modes based on the same load are shown in Fig.3, the heat transfer coefficients of envelops are under the same conditions.
Based on the simulation, it is concluded that if the thermal isolation of the floor material is improved, more energy can be stored in the floor layer, effect of energy saving will be more significant in building application.

In addition, we also carried out flow visualization and computer simulations regarding the movements of thermo-fluid inside a display cooler.
CFD Analysis.
In the present study, we simulated a steady-state velocity and temperature field of a full-scale display cooler without partition plates inside a cooling compartment, with a commercially-available CFD program (Fluent 6.2).
In this simulation, the standard k-ε turbulence model and segregated solver are used.
According to the results of the CFD simulation, uniform temperature distribution inside the chamber could be substantially influenced by the entrainment flow from the bottom-plate inlet.

The research will get a more effective ventilation model by comparing the simulation results.
It is further to verify that the simulation method is feasible, and the conclusions obtained on this basis are acceptable. 1.
According to the specific characteristics of the anatomy laboratory, I will simulate five ventilation modes with CFD technology, and then get a better ventilation mode by comparing the simulation results and the test results and provide certain reference significance for improving the air quality of the anatomy laboratory. 2.
Model V will be recalculated, and the comparison of simulation results and the measured results are shown in figure 9~10.
Figure 9 The comparison of simulation results and measured results of wind speed Figure 10 The comparison of simulation results and measured results of formaldehyde concentration 5.

Simulation results of the SSG turbulence model matched well with the experimental results [13].
On reviewing various literatures, it is understood that experimental studies, analytical studies and numerical simulations are performed for turbulent flow conditions.
Unstructured tetrahedral mesh is generated for the whole domain by ANSYS ICEM CFD 13.0©.
Numerical simulations are performed with commercial CFD code, ANSYS Fluent 13.0©.
Addad, Numerical simulations of flow and heat transfer over rib-roughened surfaces, Proceedings of the 17th Annual Conference of CFD Society of Canada, Ottawa (2009) 8 pages

Numerical simulation shows that leading edge Coănda-jet blowing was found to be helpful in increasing power generation at leading edge separation cases, while a TE blowing jet otherwise [15].
CFD simulation of the lift coefficient CL versus Coănda -jet momentum coefficient Cµ by De la Montanya et al. [20] and Harvell et al. [21] confirmed such notion, although there was a little difference in the jet slot place and shape of the airfoils, as exhibited in Figure 4.
Numerical simulation using commercially available Navier-Stokes CFD method is carried out and a critical scrutiny of the computational procedure and grid generation is performed.
Liu, Numerical simulations of the aerodynamic characteristics of circulation control wing sections, Georgia Institute of Technology, 2003
Ahuja, Numerical simulations of the steady and unsteady aerodynamic characteristics of a circulation control wing airfoil, AIAA, 2001

Simulation on Torpedo Unsteady Hydrodynamic with the Movement in the Longitudinal Plane Yang Ming, Zhao Shi-ping, Wang Han-ping, Wang Lin-peng, Wang Shao-zhu School of Aerospace Engineering, Beijing Institute of Technology, Beijing, 100081, China e-mail: yangming19850420@163.com Keywords: Underwater, Maneuvering, Unsteady, Dynamic mesh, Hydrodynamic.
In order to capture the characteristics of the flow field and estimate the hydrodynamic coefficients accurately, it needs the help of modern CFD technology.
CFD/CSD Couping Numerical Computational Methodology.
Six-DOF Simulation of Light-duty Reconnaissance and Precise Attack UAV under Unstable State Interference of Missile Separation.
(in Chinese) [6] Tian Shuling, Wu Yizhao, Xia Jian, Numerical Simulation Research of Unsteady Flow Field Around Helicopter in Forward Flight on Dynamic Overset Unstructured Grids.

In this paper, the circle perforated grid plate as a new design has been studied for the fractal grid through a simulation process.
To analyze the turbulence intensities and axial velocity commercial CFD software – Fluent 6.3 was used to in order to predict the mean axial velocity (U mean), Turbulent Intensities (U’), Urms and Vrms.
Fig. 2: Computational domain in CFD for turbulent generator with various blockage ratio and diameter of the holes The mesh quality was be evaluated using the EquiAngle Skew (QEAS) criterion, which are lower or equal to 0.2 for more than 95 % of the control volumes.
Results and Discussion Upon completion of simulation, data was extracted on a horizontal plane (centre of the cylinder).
References [1] Vassilicos, S.L.A.J.C., Direct Numerical Simulation of Fractal-Generated Turbulence. (2009)

Firstly, the ultra-high speed air bearing spindle is designed, including grooved hybrid air bearing, helical water cooling channel and built-in motor, etc; Subsequently, pneumatic hammer instability and whirl instability of air bearing are studied; The thermal-structural behaviors of the spindle system at ultra-high speeds are investigated by using structural FEA coupled CFD; Static and dynamic performance of spindle is studied to predict the stiffness, modes and natural frequencies of the spindle; Lastly, system optimizations are conducted to obtain optimal performance and dynamic behaviors of the spindle.
In order to achieve the high performance of the spindle, an integrated approach, including the design, calculations and simulations on the spindle system, should be done in the design stage, as shown in Fig. 1.
For this reason an accurate Computational Fluid Dynamics (CFD) analysis is necessary to map the stiffness of the bearings against the speed, to improve the dynamic model [14].
Based the analysis of the evaluation on the thermal loads, conduction and convection coefficients in each part of the spindle and applying energy balances both in steady-state and transient conditions, developing a thermo-structural model by using structural Finite Element Analysis (FEA) coupled Fluid Simulation (CFD) to describe the temperature distribution of a complete ultra-high speed air bearing spindle system [9].
Through simulation, calculation and optimization of the spindle system, starting from the bearing performance and ending with a comprehensive dynamic analysis of the entire system, a reliable and powerful spindle can be obtained, meeting all of the design specifications in the design stage.

The boundary layer separation is (given by CFD prediction) at s/smax = 66%.
The separation of the boundary layer occurs (by the CFD prediction) at the same point.
For t/c = 0.6 the integral values of KEL obtained by CFD are ¼ lower compared to experimental data (Fig. 4).
The numerical simulations predict that there isn´t any transition in boundary layer for all cases without boundary layer separation.
The small differences in the trends of KEL as a function of Mach number in comparison with experimental data were discovered, when the numerical simulations predict the slight increase of KEL with increasing Mach number.