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洋壳渗透率结构对其内部热液对流的影响研究——基于热力学数值模拟
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作者 范庆凯 李江海 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2020年第5期1986-1997,共12页
洋底特殊环境的限制使数值模拟成为研究海底热液对流与成矿机制的有效方法.本文通过数值模拟的方法,研究洋壳渗透率单因素变化对热液对流系统的形态和输出参数(热液喷发温度和热流值)进行研究.模拟结果表明,洋壳平均渗透率分别与热液喷... 洋底特殊环境的限制使数值模拟成为研究海底热液对流与成矿机制的有效方法.本文通过数值模拟的方法,研究洋壳渗透率单因素变化对热液对流系统的形态和输出参数(热液喷发温度和热流值)进行研究.模拟结果表明,洋壳平均渗透率分别与热液喷发温度和热量输出呈反相关和正相关关系,符合达西流体热对流的基本解析规律.另外,洋壳渗透率的垂向变化不会使洋壳内部的对流系统产生明显的横向偏移,只使热液羽规模在垂向上产生规律性变化,且渗透率越大,热液羽规模越小.渗透率在水平方向的变化则是引发热液羽和热液喷发位置横向偏移的主要因素,且只有在特定的渗透率水平变化率范围内,上涌热液羽才会发生向高渗区的明显偏移,这也从一定程度上解释了现今拆离断层相关的热液系统均未发育于断层终止线上的事实.以大西洋Trans-Atlantic Geotraverse(TAG)热液区为例,断裂带高渗区必然影响相邻洋壳内部热液的上涌路径,但受区内拆离断裂带周缘的渗透率水平变化规律的影响,上涌热液羽不至于完全偏移至断裂带,从而产生拆离断层上盘的热液活动. 展开更多
关键词 热力学数值模拟 热液对流 喷发温度 热流值 相位差
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Furnace structure analysis for copper flash continuous smelting based on numerical simulation 被引量:7
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作者 汪金良 陈亚州 +1 位作者 张文海 张传福 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第12期3799-3807,共9页
According to the innate characteristic of four types of furnace, the copper flash continuous smelting (CFCS) furnace can be considered a synthetic reactor of two relatively independent processes: flash matte smelti... According to the innate characteristic of four types of furnace, the copper flash continuous smelting (CFCS) furnace can be considered a synthetic reactor of two relatively independent processes: flash matte smelting process (FMSP) and copper continuous converting process (CCCP). Then, the CFCS thermodynamic model was proposed by establishing the multi-phase equilibrium model of FMSP and the local-equilibrium model of CCCP, respectively, and by combining them through the smelting intermediates. Subsequently, the influences of the furnace structures were investigated using the model on the formation of blister copper, the Fe3O4 behavior, the copper loss in slag and the copper recovery rate. The results show that the type D furnace, with double flues and a slag partition wall, is an ideal CFCS reactor compared with the other three types furnaces. For CFCS, it is effective to design a partition wall in the furnace to make FMSP and CCCP perform in two relatively independent zones, respectively, and to make smelting gas and converting gas discharge from respective flues. 展开更多
关键词 furnace structure copper flash continuous smelting numerical simulation thermodynamic analysis
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NUMERICAL SIMULATION EXPERIMENTS OF THE IMPACTS OF LOCAL LAND-SEA THERMODYNAMIC CONTRASTS ON THE SCS SUMMER MONSOON ONSET 被引量:2
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作者 任雪娟 钱永甫 《Journal of Tropical Meteorology》 SCIE 2003年第1期1-8,共8页
The important effects of local land-sea thermodynamic contrast between the South China Sea (SCS) and Indochina Peninsula on SCS summer monsoon onset are preliminarily studied by using two sets of SSTA tests and two id... The important effects of local land-sea thermodynamic contrast between the South China Sea (SCS) and Indochina Peninsula on SCS summer monsoon onset are preliminarily studied by using two sets of SSTA tests and two ideal tests in s-p regional climate model. The result shows that warm SST in the SCS in winter and spring is favorable for the formation of monsoon circulation throughout all levels of the atmosphere over the sea, which hastens the onset of SCS summer monsoon. The effects of cold SST are generally the opposite. The local land-sea contrast in the SCS is one of the possible reasons for SCS summer monsoon onset. Superposed upon large-scale land-sea thermodynamic differences, it facilitates the formation of out-breaking onset characteristics of SCS summer monsoon in the SCS area. 展开更多
关键词 local land-sea thermodynamic contrast SCS summer monsoon p-σregional climate model
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Fluid-solid coupling numerical simulation of charge process in variable-mass thermodynamic system 被引量:8
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作者 胡继敏 金家善 严志腾 《Journal of Central South University》 SCIE EI CAS 2012年第4期1063-1072,共10页
Abstract: A joint solution model of variabk:-mass flow in two-phase region and fluid-solid coupling heat transfer, concerned about the charge process of variable-mass thermodynamic system, is built up and calculated... Abstract: A joint solution model of variabk:-mass flow in two-phase region and fluid-solid coupling heat transfer, concerned about the charge process of variable-mass thermodynamic system, is built up and calculated by the finite element method (FEM). The results are basically consistent with relative experimental data. The calculated average heat transfer coefficient reaches 1.7~105 W/(m2. K). When the equal percentage valve is used, the system needs the minimum requirements of valve control, but brings the highest construction cost. With the: decrease of initial steam pressure, the heat transfer intensity also weakens but the steam flow increases. With the initial water filling coefficient increasing or the temperature of steam supply decreasing, the amount of accumulative steam flow increases with the growth of steam pressure. When the pressure of steam supply drops, the steam flow gradient increases during the maximum opening period of control valve, and causes the maximum steam flow to increase. 展开更多
关键词 steam accumulator variable-mass control valve fluid-solid coupling numerical simulation
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Numerical Study on Heat Transfer Enhancement for Use of Corrugated, Nodal and Horizontal Grain Tubes 被引量:1
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作者 朱家玲 王钰沛 +1 位作者 张伟 刘雪玲 《Transactions of Tianjin University》 EI CAS 2014年第5期385-392,共8页
With isopentane as working fluid, the heat transfer performances for corrugated, nodal and horizontal grain tubes are simulated. The structural parameters of the three kinds of tubes are compared with those of the pla... With isopentane as working fluid, the heat transfer performances for corrugated, nodal and horizontal grain tubes are simulated. The structural parameters of the three kinds of tubes are compared with those of the plain tube. The numerical results using computational fluid dynamics are validated with theoretical values. For the corrugated, nodal and horizontal grain tubes, the heat transfer enhancements(HTEs) are 2.31—2.53, 1.18—1.86 and 1.02—1.31 times of those of the plain tube, respectively. However, the improved HTEs are at the expense of pressure losses. The drag coefficients are 6.10—7.09, 2.06—11.03 and 0.53—1.83 higher, respectively. From the viewpoint of comprehensive heat transfer factor, the corrugated tube is recommended for engineering applications, followed by the horizontal grain tube. 展开更多
关键词 corrugated tube nodal tube horizontal grain tube heat transfer
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Analysis of Particle Behavior in High-Velocity Oxy-Fuel Thermal Spraying Process 被引量:3
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作者 Hiroshi Katanoda Kazuyasu Matsuo 《Journal of Thermal Science》 SCIE EI CAS CSCD 2003年第3期279-282,共4页
This paper analyzes the behavior of coating particle as Well as the gas flow both of inside and outside the High-Velocity Oxy-Fuel (HVOF) thermal spraying gun by using quasi-one-dimensional analysis and numerical simu... This paper analyzes the behavior of coating particle as Well as the gas flow both of inside and outside the High-Velocity Oxy-Fuel (HVOF) thermal spraying gun by using quasi-one-dimensional analysis and numerical simulation. The HVOF gun in the present analysis is an axisymmetric convergent-divergent nozzle with the design Mach number of 2.0 followed by a straight passage called barrel. In the present analysis it is assumed that the influence of the particles injected in the gas flow is neglected, and the interaction between the particles is also neglected. The gas flow in the gun is assumed to be quasi-one-dimensional adiabatic flow. The velocity, temperature and density of gas in the jet discharged from the barrel exit are predicted by solving Navier-Stokes equations numerically. The particle equation of motion is numerically integrated using three-step Runge-Kutta method. The drag coefficient of the particle is calculated by linear interpolation of the experimental data obtained in the past. Particle mean temperature is calculated by using Ranz and Marchalls' correlation for spherical particles. From the present analysis, the distributions of velocity and temperature of the coating particles flying inside and outside the HVOF gun are predicted. 展开更多
关键词 supersonic nozzle supersonic jet thermal spraying gas-particle flow.
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Percolation Phase Transitions from Second Order to First Order in Random Networks
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作者 贾啸 洪劲松 +4 位作者 杨宏春 杨春 付传技 胡建全 史晓红 《Communications in Theoretical Physics》 SCIE CAS CSCD 2015年第4期515-519,共5页
We investigate a percolation process where an additional parameter q is used to interpolate between the classical Erd¨os–R′enyi(ER) network model and the smallest cluster(SC) model. This model becomes the ER ne... We investigate a percolation process where an additional parameter q is used to interpolate between the classical Erd¨os–R′enyi(ER) network model and the smallest cluster(SC) model. This model becomes the ER network at q = 1, which is characterized by a robust second order phase transition. When q = 0, this model recovers to the SC model which exhibits a first order phase transition. To study how the percolation phase transition changes from second order to first order with the decrease of the value of q from 1 to 0, the numerical simulations study the final vanishing moment of the each existing cluster except the N-cluster in the percolation process. For the continuous phase transition,it is shown that the tail of the graph of the final vanishing moment has the characteristic of the convexity. While for the discontinuous phase transition, the graph of the final vanishing moment possesses the characteristic of the concavity.Just before the critical point, it is found that the ratio between the maximum of the sequential vanishing clusters sizes and the network size N can be used to decide the phase transition type. We show that when the ratio is larger than or equal to zero in the thermodynamic limit, the percolation phase transition is first or second order respectively. For our model, the numerical simulations indicate that there exists a tricritical point qcwhich is estimated to be between0.2 < qc< 0.25 separating the two phase transition types. 展开更多
关键词 PERCOLATION NETWORKS
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