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In order to get insights into the heat transfer of supercritical LNG, numerical simulations were carried out in this paper for investigating heat transfer of LNG in horizontal circular tubes under supercritical pressure.
The accuracy of numerical simulations of heat transfer in supercritical fluid may depend on turbulence models.
Previous CFD study [1] using the Fluent code revealed the RNG turbulence model gives reasonable results in predicting heat transfer of supercritical water, therefore the RNG turbulence model was used in this study. u is the velocity vector, while is velocity component in special direction .
Numerical computations were carried out using the popular CFD package Fluent 6.3.26 [3].
Fig. 3 Velocity distributions on the tube symmetric plane Fig. 4 Pressure distributions on the tube symmetric plane Conclusions Three-dimensional computational fluid dynamics (CFD) based modeling and simulation have been conducted to investigate the heat transfer and flow performances of supercritical LNG in the horizontal circular tubes for application in LNG vaporization.

In this paper, we perform numerical simulation on CFD software.
Numerical simulation In this paper, we use the DN32 PE tube as U buried tube, and we use CFD software to simulate the change of soil temperature field under different moisture.
, we concluded the following: after the same period of time heat exchanging, heat effect of heat exchanger in experimental measure is wider than that in numerical simulation.
The main reason is that numerical simulation simplifies the pipe buried model in that field experiment is affected by many other unknown factors.
In this way, there are some disagreement between the simulation and the field experiment.

Numerical Simulation for Part Effect of Ventilation of Extra-long Road Tunnel Sheng Liu1a, Guanglong Zhang2b, Xiaowei Liu2b 1School of Science, Chang’an University, Xi’an, Shaanxi Province, 710064, China 2School of Highway, Chang’an University, Xi’an, Shaanxi Province, 710064, China a86128875@163.com, b87596240@163.com Key words: highway tunnel; semi-transverse ventilation system; part effect; numerical simulation Abstract.
Part resistance coefficients that numerical simulation of the semi-transverse Ventilation under various work condition needs are obtained.
CFD Part Numerical Simulation Distributary resistance coefficient.
The pressures provided by the simulation for jet fan in states of tailwind and windward are both less than standard value showing the failure of expected surge effect.
CFD simulation of fire smoke behavior with transverse ventilation comparison with model test[A]. 10th I SAVVT[C].

Study on the Airflow Level Posture Sensor Based on Fluid-Solid coupling Ming-Ming Ji1, a, Lin-Hua Piao2, b, Bai-Hua Li3,c 1Beijing Information Science and Technology University, Beijing China 2Beijing Information Science and Technology University, Beijing China 3Beijing Information Science and Technology University, Beijing China ajmm3862411@126.com, bbjplh@bistu.edu.cn, clibaihua0226@yahoo.cn Key words: three-dimensional; airflow level posture sensor; ansys-flotran cfd; Fluid-Solid coupling Abstract.
Using ANSYS program, the finite element simulation based on Fluid-Solid coupling is conducted by a series of procedures, such as three-dimensional model building of airflow level posture sensor according to the actual size of the proportion, network modifying, loads applying and equation solving.
The numerical results show that: 1) The velocity difference of air flow at two heat source changes with the tilt angle, the difference between airflow velocity increases with the increase of the tilt angle. 2)Compared with two-dimensional modeling, the simulation result of three-dimensional modeling and fluid-solid analysis methods are more comprehensive and accurate, which provides more reliable basis for practical research of the airflow level posture sensor.
Analysis method Using FLOTRAN CFD module of ANSYS software and the application of fluid-structure interaction analyzed fluid transmission between heat and air.
Conclusions The finite element method based on fluid-structure interaction, three-dimensional model of sensitive components of air flow posture sensor is built, using ANSYS-FLOTRAN CFD software to calculate the flow velocity inside airflow posture sensor in the horizontal and inclined state distribution.

In this study, computational fluid dynamic(CFD) simulation is performed to study the aerodynamic characteristics of the trajectory correction fuze.
In this study, the radial dimension of simulation region is 15 times the radius of the projectile,and the length is 10 times the length of the projectile.[7] b) Mesh Generation The mesh is the carrier of the numerical simulation.
In this study, the simulation model used unstructed grid method.
Selection of turbulence in a aerodynamical simulation of a missile [J].
[10]ANSYS ICEM CFD 14.0 User’s Guide, ANSYS Inc. .

With the development of calculation technique, CFD technology has been widely used.
Specifically, appropriate mesh generation is typically a major difficulty in CFD.
Numerical simulation result shows that the high order Lagrange interpolation may cause numerical oscillation.
Consequently, velocity support domain should be larger than pressure support domain in the numerical simulation model.
Calculation simulation shows a good agreement with the Fluent result.

Using CFD software, the mean wake fraction and thrust deduction fraction are obtained by simulating the flow field around submarine with equally distributed body force adopted to simulate the affection of propeller.
With the development of computer technology, CFD simulation of submarine powering performance in the numerical towing tank has been developed and validated[1], and the three dimensional body forces were also adopted to model the affection of the guide vane and propeller[2].
The objective of this work is to study the numerical method for prediction of submarine powering performance without knowing propeller force by using CFD software.
Numerical simulation of submarine self-propulsion test In order to study the submarine powering performance, the propeller 4118[3] is installed to the stern hull of SUBOFF AFF-8[4] submarine model, as shown in Fig. 1, and the axial installation position is z/L=0.9639, where is the length of the submarine model.

The simulation is carried out to study the influence of different temperature and doping levels on the electrochemical performance of the cell.
The geometry used in simulation is shown in Fig. 1b and the dimensions are mentioned in Table 1.
Fig 2 (a) Comparison of model and experimental results (b) effect of temperature on performance (c) effect of doping level on performance Results and Discussions At first, the model is validated and then used for further simulations.
CFD modelling is also useful in prediction of quantities which cannot be measured in-situ such spatial distribution of species mass fraction as shown in Fig. 3(a-c).
The current work uses CFD modelling to stress the importance of choosing optimum operational conditions and effective material properties for achieving good performance.

By applying the FLUENT software of CFD, a three-dimensional model about the V-cone flow meter is built.
The effect of technical parameters on flow in the V-cone flow meter field has been studied by using computational fluid dynamics (CFD).
The simulation outflow coefficient is relevant to the parameter of the effective diameter ratio β, the diameter of pipe D, front-cone angleα and back-cone angleθ.
By calculating the Reynolds number of the smallest entrance velocity, it can be figured out that the flow field of the numerical simulation is turbulence.
Conclusions The simulation outflow coefficient formula is relevant to the parameter of the effective diameter ratio β, the diameter of pipe D, the front cone angleα and the back cone angleθ.

The dynamic characteristics of a hydrostatic and hydrodynamic journal bearing with two arrays of eight holes have been investigated theoretically by the three-dimensional Computational Fluid Dynamics (CFD) models with respect to equilibrium position.
This paper presents an analytical study of the dynamic stiffness and damping of hybrid journal bearings with two arrays of eight holes using a three dimension CFD model which associated with displacement disturbance and velocity disturbance through a UDF (User Definition Function) program.
CFD model of the bearings A 3-D simulation model is developed using the CFD package FLUENT 6.3.
The dimensions of the journal bearing with two arrays of eight holes used in this simulation are: diameter 30mm, bearing clearance 20μm, length to diameter ratios 0.4, orifice diameter 0.6, eccentricity 0.1, as shown in Fig.1.
Conclusions The dynamic characteristics of hybrid (hydrostatic/hydrodynamic) journal bearing with two arrays of eight holes are analyzed theoretically by the CFD approach under the action of displacements disturbance and velocity disturbance.