李宝宽
,
顾明言
,
齐凤升
,
王芳
,
周谦
金属学报
建立了底吹钢包内气/钢液/渣三相流动数学模型, 利用多相流动体积法(VOF)模拟了渣层运
动行为. 模型结果再现了底吹钢包内气/钢液/渣三相流动现象. 当Ar气被吹进钢包时, 在
钢液内产生气泡, 上升的气泡间 歇地冲击并突破渣层, 产生渣眼; 同时, 渣层发生波动,
波动频率随着Ar气流量的增加而增加. 参数研究显示: 220 t钢包底吹流量由100增加到
300 L/min, 渣眼直径由0.43增加到 0.81 m. 计算的无量纲渣眼面积与文献中渣眼的实
验结果很接近. Ar气喷吹期间, 渣层发生重大的变形, 近渣眼处的渣层变薄, 近钢包壁
处的渣层变厚. 渣眼周围钢液流速很大, 并导致部分渣滴卷入钢液中.
关键词:
钢包
,
Slag layer behavior
,
Three-phase flow
,
Mathematical model
Jiansong YE
,
Yikang LIU
,
Yuanjun ZHOU
材料科学技术（英文）
A temperature phase transformation stress coupled 3D nonlinear mathematical model has been proposed for forecasting distortion of workpieces on the cooling processes in this paper. Moreover, a series of subroutines were developed on the MARC (analysis research corporation) software platform and the simulation result is basically identical with the experimental one that measured on the workpiece shape with LEITZ equipment. This verifies that the mathematical model and method are feasible.
关键词:
Mathematical model
,
null
,
null
Zhoushun ZHENG
,
Xuanhui QU
,
Yunping LI
,
Jianfeng GUO
材料科学技术（英文）
A mathematical model of two-dimensional flows of PIM derived from the momentum, continuity equations and the heat transfer equation is obtained. The formula of calculating the flow conductance and the pressure equation are deduced when the no slip boundary condition is employed at the wall, and the pressure equation is a non-linear elliptic partial differential equation. The flow front locations, distribution of velocities, temperature and pressure are simulated by the finite element analysis software ANSYS. Simulation results indicate that it is in the final filled part that defects appear easily. The region in which the defects may occur during the PIM process can be predicted.
关键词:
Numerical simulation
,
null
,
null
,
null
L.Z. Chang
金属学报(英文版)
The method based on transient heat transfer model
is adopted to simulate electro-slag remelting process. The
calculated results of the model show that the process is in the
quasi-steady state, and the shape of pool remains unchanged when the
height of ingot is approximately 2.5--3 times the thickness of slab
ingot. The change in the shape of pool is found to be strongly
dependent on the pattern of melting rate, and hence, the power
input; the depth of the molten pool increases with the increase in
melting speed. It is concluded that a transient heat transfer model
has to be used to obtain reliable input information for the entire
operating time.
关键词:
ESR
,
null
,
null
,
null
Weizhen OUYANG
,
Xia CAO2
,
Ning WANG
金属学报(英文版)
The aim of this article was to theoretically study diffusion and migration of chloride ions during electrochemical chloride removal. The proposed model would enable optimization of its application by predicting the optimal treatment time and current combination. A mathematical model for simulating the transport behavior of chloride ions was developed by consideration of diffusion and migration of chloride ions when a constant DC current density was applied through the marine cast iron artifacts. The corresponding tests were conducted to validate the mathematical model. This model predicted the data of the extraction ratio of the chloride ion that correlated satisfactorily with the experimental values. An important issue in electrochemical chloride removal was to understand how chloride ions moved, taking account of diffusion and migration of chloride ions and the release of binding chloride ions. The effects of the treatment time, externally applied current density, chloride diffusion coefficient, and rate constant of release of binding chloride ion on chloride removal are studied. The specific quantitative details applied to one-dimensional model were discussed here. This article has proposed a mathematical model for the first time, which was showed to be a useful tool that can reveal the ionic transport mechanism and optimize the application during electrochemical chloride removal.
关键词:
Marine cast iron
,
null
,
null
