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稳态电流理论 电磁学 稳态电流 电流守恒 电流守恒是自然界的基本定律，用方程形式可以表示为 (1) 其中， 是电流密度矢量， 是空间电荷密度。在稳态电流或直流电（DC）这些重要的特殊情况下，下式成立 (2) 因此，直流电流的方程为 (3) 这个方程在数学上类似于自由空间中的静电方程。另外，就像静电情况一样，麦克斯韦方程组暗示了电场需要满足无旋（无旋度）场的额外要求。 (4) 这是在稳态电流理论中没有电磁感应的另一种说法。
多物理场仿真百科 -
cn.comsol.com/multiphysics ...
本例介绍一维稳态热分析，其中包括指定环境温度下的辐射。
将根据该基准模型的解得到的温度场与 NAFEMS 基准解进行了比较。
案例下载 -
cn.comsol.com/model/266
本例介绍二维稳态热分析，其中包括与指定外部（环境）温度的热对流。这是一个基准示例。
目标位置的基准结果是温度 18.25 C。COMSOL Multiphysics 模型使用 556 个单元的默认网格，得出的温度为 18.28 C。经过连续均匀的细化，温度为 18.26 C 和 18.25 C，表明温度向基准结果收敛。
案例下载 -
cn.comsol.com/model/265
此模型阐明如何使用“传热”接口构建和求解传导传热问题。模型取自 NAFEMS 基准集合，演示轴对称稳态热分析。与 NAFEMS 基准模型不同，我们在此模型中使用温度单位开尔文，而不是摄氏度。
案例下载 -
cn.comsol.com/model/453
Because the time scale of gas flow within the landfill isn’t remarkable, the gas flow can be approximated as a quasi-steady state, and in this case gas flow is calculated by stationary interface.
论文和技术资料 -
cn.comsol.com/paper/30993
Thus simulations of transient developments do not require an artificial initialization phase to obtain an approximation of the steady state. Also a pre-run for direct solution of the steady state, as alternative to transient initialization, becomes obsolete.
Moreover the analytical steady state solution can be used as a reference to compare transient deformations during the simulation.
论文和技术资料 -
cn.comsol.com/paper/52151
Previously reported microheaters at COMSOL® conferences have shed light on microheaters’ thermal properties, optimized geometries and power consumption—all based on steady-state analysis. In this work, we additionally report transient analysis, i.e., thermal transient response of a microheater to study the time required for a microheater to reach the intended operating temperature.
论文和技术资料 -
cn.comsol.com/paper/66141
The results show that the pipe spacing and the heat capacity ratio play an important role in the transient behavior of the BHE internal resistance, whereas the pipe spacing and the conductivity ratio play an important role in the steady value of the BHE thermal resistance.
论文和技术资料 -
cn.comsol.com/paper/18885
The manual syringe was assumed to have a constant pressure, and thus was modelled in steady state. The auto-injector was modelled in a transient state that had a changing inlet pressure over time due to assuming a spring force.
论文和技术资料 -
cn.comsol.com/paper/51122
当树枝触及高架电缆时会产生瞬间短路，然后您的灯可能会闪烁。有一种称为自动重合器的装置，它可以确保输送到您家里的电力不会被长时间切断。
ABB AG 是一家在电力技术方面处于领先地位的制造商，他们正在努力设计一种更可靠的自动重合器。本次设计过程的一个目标是优化永久磁体尺寸的同时确保开关特性出众。
为了做到这一点，ABB AG 使用 AC/DC 模块创建了二维仿真并计算了磁通密度。接下来，他们使用了电路接口将实际功率放大电路原理图和元件值耦合到磁体仿真中。最后，在优化软件中不断输入结果以选择适当大小的磁体，然后使用 LiveLink™ for MATLAB® 将其导回 COMSOL Multiphysics，在三维模型中对设计进行验证。
用户案例 -
cn.comsol.com/story/16429
The steady-state non-equilibrium distributions of two species of mono-valent ions around a charged nanofluidic channel have been examined.
论文和技术资料 -
cn.comsol.com/paper/5418
Finite element modeling of three phase three limbed transformer requires solving of field and circuit variables simultaneously. The accurate modeling thus obtained could predict asymmetry in magnetizing current of three phases due to asymmetry in core of three limbed transformer.
This work includes circuit field coupling using COMSOL Multiphysics’ ACDC module.
论文和技术资料 -
cn.comsol.com/paper/14933
In this work, the fluid flow over a 2D backward-facing step is analyzed in order to provide a case study for the use of different models for the blood dynamic viscosity in COMSOL Multiphysics. Three non-Newtonian models, as well as the Newtonian model are used to study the shear stresses and the reattachment length as a function of the fluid speed. The non-Newtonian models used in this study are the Carreau model, the power law model, and one of its variants, the Walburn-Schneck model.
论文和技术资料 -
cn.comsol.com/paper/6540
Simulation models for steady state thermal hydraulics analyses of ORNL’s HFIR have been developed using COMSOL.
论文和技术资料 -
cn.comsol.com/paper/12967
A 3D model of a magnetic rotor both rotating and translationally moving at high-speed over a conductive guideway is modeled in steady-state using the convective A*-Φ formulation.
论文和技术资料 -
cn.comsol.com/paper/6387
This paper presents steady and unsteady computational results obtained from numerical solutions of the full two-dimensional governing equations for annular internal condensing flows in a channel.
论文和技术资料 -
cn.comsol.com/paper/15617
An FEA model of a steady state thermal interface material characterization apparatus was created in COMSOL Multiphysics 4.2a. This model was then fitted using three convection heat loss coefficients and the conductance of the TIM layer to a set of experimental measurements made using a steady state apparatus. It was shown that the model successfully matched the measured temperature values and the TIM conductance determined using the one dimensional assumption in the case which was examined.
论文和技术资料 -
cn.comsol.com/paper/13070
Current transfer from high-pressure arc plasmas to thermionic cathodes may occur in a diffuse mode, when the current is distributed over the front surface of the cathode, or in a spot mode, when most of the current is localized in one or more small areas.
Spectra of perturbations of 3D steady-state current transfer to thermionic cathodes of a high-pressure argon arc have been computed in the framework of the model of nonlinear surface heating.
论文和技术资料 -
cn.comsol.com/paper/5322
The methodology has been developed using MATLAB/COMSOL platform and is currently capable of simulating film-wise condensation for steady and unsteady flows. The results obtained are shown to be in agreement with an independently developed quasi-one-dimensional technique as well as a two-dimensional technique.
论文和技术资料 -
cn.comsol.com/paper/8861
The time-dependent fluid flow and thermal interactions have been solved for transient and steady state conditions of the conjugate heat transfer problem between the natural convective flow and heat sinks composed of arrays of pins.
论文和技术资料 -
cn.comsol.com/paper/15911