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Experimental Study and Numerical Simulation on Thermal Energy Storage Characteristics of Composite Phase Change Materials in Annular Space of Vertical Double-pipe Heat Exchanger LIU Xiaohong1, a, LING Ziye2, b, SUN Peng2, c, FANG Xiaoming2, d, XU Tao2, e, ZHANG Zhengguo2, f * 1Automotive Department, Guangdong Industry Technical College, Guangzhou 510300, China. 2Key Laboratory of Enhanced Heat Transfer and Energy Conservation, the Ministry of Education, South China University of Technology, Guangzhou 510640, China a1243360323@qq.com, bling.ziye@mail.scut.edu.cn, csun.peng@mail.scut.edu.cn, dcexmfang@scut.edu.cn, e xt771120@163.com, fcezhang68@163.com Key words: Composite phase change material, Thermal storage, Expanded graphite, Numerical simulation Abstract: Experimental system on thermal energy storage characteristics of phase change materials (PCMs) in annular space of a vertical double-pipe heat exchanger was set up.
The temperature fields of composite PCM in different time are obtained by numerical simulation method, the measured temperatures and simulation results are in good agreement.
Commercial Computational Fluid Dynamics (CFD) software FLUENT 5.6 is used to simulate the thermal storage process of composite PCMs.
Li, Experiment test of thermal conductivity coefficient and heat transfer simulation analysis of fatty acids phase change materials, Journal of Functional Materials, 43(2012) 1950-1954,1959

The possibility of its use for simulation of mini- and microchannel flow is shown in [7,8].
The temperature dependence of the water thermophysical properties was taken into account in the simulation.
The simulation of turbulence was conducted using the standard model Menter SST [28].
Dekterev, Simulation of flows in micromixers, Thermophysics & Aeromechanics (2010) 565-576
Minakov, Computer modelling of heat and mass transfer processes in microchannels using CFD-package SigmaFlow, Computer research and modeling (2012) 781-793

Detailed numerical simulation of short-term microgravity experiments to determine heat conductivity of melts Viktor Bánhidi1, a , Tamas J.
,Hódmezővásárhely, Pf179., H6800 Hungary 2 Deparment of Polymer Engineering, University of Miskolc, Miskolc, H3515,Hungary a banhidiviktor@gmail.com, btamassjsz@gmail.com Keywords: microgravity, heat conductivity, finite element (volume) method, fluent, simulation, CFD Abstract.
In these simulations we included parameters which are usually neglected in other "straight" numerical methods [11, 12].
Complex FVM simulations (FLUE)T of Ansys Inc.).
This is true as long as sufficiently precise thermal and rheological parameters are included in the simulation.

In this study, a computational fluid dynamics (CFD) study based on a finite element method (FEM) was performed for the human aorta with four different flow time patterns (healthy to full intra-aorta pump support).
[5] YJ Xuan, Y Chang, KY Gu, et al, “Hemodynamic Simulation Study of a Novel Intra-Aorta Left Ventricular Assist Decice,” ASAIO JOURNAL, USA, 58(5), pp: 462-469, September, 2012
Ladd, “Numerical simulations of particulate suspensions via a discretized Boltzmann equation.
Ladd, “Numerical simulations of particulate suspensions via a discretized Boltzmann equation.
Tarbell, “Numerical simulation of pulsatile flow in a compliant curved tube model of a coronary artery,’’ .

Numerical simulation for gas-liquid two-phase flow along the borehole after air cutting Xiaofeng Sun1,a , Junbo Qu1,b , Tie Yan1,c ,Li Wang1,d 1Key Laboratory of Enhancing Oil and Gas Recovery in Ministry of Education,NorthEast Petroleum University,Daqing,Heilongjiang ,China 163318 asuneye@126.com,bqjbday@126.com, cyant@nepu.edu.cn, dqjbsir@163.com Keywords: Numerical simulation; Gas kick;Gas kick simulation; Well control Abstract.
Analysis of the simulation results The simulation results of group1,group2,group3 are similar, when gas invasion with fixed displacement at the speed of 0.005kg/m3, gas groups gathere at the wellbore bottom and then become large taylor bubbles during the period 0~1second[4]. 9 seconds after gas invasion, bottom of the wellbore forms stable bubble flow, distribution of gas-liquid two-phase close to steady state, bubbles disperses evenly, this process is similar to the air-underbalanced drilling, pressure of bottom hole is roughly constant.
Pressures of bottom hole vary hole and wellhead f conbination 1 distribution of combination 4 characteristics of different combinations Conclusions Establish the physical model to simulate accidents of well bottom and apply the numerical simulation methods to decrease equations, it provides very good ways to solve the transient problems of gas cut, and canrepeat the development process from gas cut to blowout .
Quantitatively calculate the different amount of gas cut and the distribution parameters of downhole ,and it is a important reference to recognize the time of flow pattern transition and the rule of blowout.When simulation gas cut under different boundary conditions, the pressure of bottom hole decreases with the increasing time of gas cut; when the quality of gas cut is constant, pressure of hole bottom begans to keep constant after reaching the minimum and no longer drop; when the pressure of gas cut is certain, pressures of bottom hole appear a significant turning point after reaching the minimum, then fluid form annular flow pattern,the process is more closer to the actual situation of blowout.
Computational fluid dynamics and Principle & application of CFD software Tsinghua university press, 2004:P 1-111, in Chinese

FDS is a popular computational fluid dynamics (CFD) tool in fire related researches [5].
The most important input variable to fire simulations is the evolution of heat release rate (HRR) with time [7].
The process was followed by a computerized simulation using PyroSim software (the graphic interface for FDS).
Anghel, Contribution on fire modelling and simulation through numerical method, doctoral thesis, Petroleum-Gas University of Ploieşti, 2009, pp. 10
Panaitescu, Modelling and simulation of ventilation in fire emergency situation, Computational Civil Engineering, 2008, Iaşi, pp. 421-429

The suggestions are supported with calculations aided by computational fluid dynamics simulations.
In order to estimate the ṡ and �� values relevant to flow within CR and TR, the current experiments were reconstructed using computational fluid dynamics (CFD) simulations with the aid of a commercial package known as Flow-3D [3].
Enhanced ṡ and �� magnitudes were observed from CFD simulations at the position indicated by the arrow in Fig 4 which, in both cases, corresponds to the entry point to the runner channel leading to the tensile test piece.

Modeling and Numerical Investigations for Launching a Free-flight Models Using Light-gas Propulsion Technology LU Xina, ZHOU Yan-huangb and YU Yong-gangc School of Energy and Power Engineering, Nanjing University of Science and Technology Nanjing, China, 210094 aluxin@mail.njust.edu.cn, bzhouyh@mail.njust.edu.cn, cyyg801@mail.njust.edu.cn Keywords: Two-stage light-gas launcher; Mathematical model; Numerical simulation; Launching performance Abstract.
The development of the CFD simulation and new instrumentation measurement techniques have aided greatly in obtaining a better understanding of the complex internal ballistic processes, as evidenced by the large gains in velocity that have been achieved in the last decade.
The control equations in pump tube are as follows: 1) Continuity equation (6) In Eq. 6, and are density and velocity of helium gas in pump tube respectively, and is cross-sectional area of pump tube. 2) Momentum equation (7) In Eq. 7, is pressure of helium gas in pump tube, and are drag coefficient and pressure loss factor respectively, and are diameter and length of light-gas chamber respectively. 3) Energy equation (8) In Eq. 8, is specific internal energy of helium gas, and Nu are thermal conductivity and Nusselt number of helium respectively, and are helium temperature and wall temperature respectively. 4) State equation of light-gas (9) In Eq. 9, and are specific heat ratio and covolume of helium. 2 Numerical Simulation Results A 30mm/120mm light-gas launcher is taken for numerical simulation using the mathematical model established in the above section.
Fig. 2 The variation of calculated piston and Fig. 3 The variation of calculated pressure on projectile velocity versus time pump versus time Fig. 4 The variation of calculated piston velocity Fig. 5 The variation of calculated projectile along with pump tube velocity along with launch tube Summary From the numerical simulation above, it can be seen that the predicted results show the general characters and trends about the firing process of two-stage light-gas launcher.

In order to verify thermal comfort of a four-ducted air-conditioning system equipped on a 12-meter-long highway sleeper coach, the thermal environment inside the compartment was numerical investigated with Computational Fluid Dynamics (CFD).
The influence of solar radiation was considered in simulation.
The commercial code Fluent was used for simulation.
Overall, the temperature of simulation is higher than that of experiment, and feet temperature is relatively high.

According to the actual condition select four different pressure value simulation,such as shown in table 1.
The simulation field of automotive redirector as the export connected pumping:the inlet pressure Ps =700000Pa,the outlet pressure Ps=-90000Pa flow field simulation results as shown in figure 3, 4, 5.
Auto power steering gear flow channel model simulation numerical results provide a basis for ejector designing.
References [1] Zhanzhong Han , Jing Wang Fluid engineering simulation calculation examples and applications Beijing Institute of Technology Press 2004.
(In Chinese) [3] Desheng Zhang , Jiyu Zhao Flow field analysis and structure optimization of peach shaped chamber hydrodynamic coupling based on CFD China university of mining and technology journal 2010 687-692.