Thermodynamics, Electrodynamics, and Ferrofluid Dynamics
Thermodynamics, Electrodynamics, and Ferrofluid Dynamics
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热力学、电动力学和铁磁流体动力学
DOI：
10.1007/978-3-540-85387-9_2
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发表时间：
2009
期刊：
影响因子：
--
通讯作者：
K. Stierstadt
中科院分区：
文献类型：
--
作者：
M. Liu;K. Stierstadt
本评论表明，一致地应用热力学并与其他一般原理（特别是守恒定律和变换性质）结合，可以在宏观电磁学中获得有用的见解和明确的结果。首先，静态麦克斯韦方程组被证明是平衡条件，表示熵是最大的相对于电场和磁场的变化。然后，从定域性、电荷守恒和热力学第二定律出发，推导出包括耗散场在内的完整动力学麦克斯韦方程组，并以类似的方式得到麦克斯韦应力，首先考虑极化或磁化介质压缩和剪切时的能量变化，然后将其作为守恒总动量（包括物质和场的贡献）的通量重新推导。只有第二种方法产生的非平衡，耗散贡献的领域。所有已知的电磁力（包括洛仑兹力、开尔文力、转动力矩M ×H）都包含在麦克斯韦应力中。当较大的磁性颗粒成团或成链时，相关磁化强度M1的弛豫时间τ变大，在典型的实验中很容易超过频率或剪切速率的倒数，即τ ε 1/ω，1/γ。因此，M1需要作为一个独立变量。导出了运动方程和应力张量及能流的相应修正。扩大的方程组被示出为解释剪切稀化，即磁增强剪切粘度在高剪切极限γτ ε 1下强烈减小的事实。毫无疑问，它也可以解释其他高频和高剪切效应。
Applying thermodynamics consistently and in conjunction with other general principles (especially conservation laws and transformation properties) is shown in this review to lead to useful insights and unambiguous results in macroscopic electromagnetism. First, the static Maxwell equations are shown to be equilibrium conditions, expressing that entropy is maximal with respect to variations of the electric and magnetic fields. Then, the full dynamic Maxwell equations, including dissipative fields, are derived from locality, charge conservation, and the second law of thermodynamics.The Maxwell stress is obtained in a similar fashion, first by considering the energy change when a polarized or magnetized medium is compressed and sheared, then rederived by taking it as the flux of the conserved total momentum (that includes both material and field contributions). Only the second method yields off-equilibrium, dissipative contributions from the fields. All known electromagnetic forces (including the Lorentz force, the Kelvin force, the rotational torqueM×H) are shown to be included in the Maxwell stress. The derived expressions remain valid for polydisperse ferrofluids and are well capable of accounting for magneto-viscous effects.When the larger magnetic particles cluster, or form chains, the relaxation time τ of the associated magnetizationM1becomes large and may easily exceed the inverse frequency or shear rate, τ ≳ 1/ω, 1/γ, in typical experiments. ThenM1needs to be included as an independent variable. An equation of motion and the associated modifications of the stress tensor and the energy flux are derived. The enlarged set of equations is shown to account for shear thinning, the fact that the magnetically enhanced shear viscosity is strongly diminished in the high-shear limit, γτ≫1. There is no doubt that it would account for other high-frequency and high-shear effects as well.
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电场在液体电介质中产生的超压的实验测定
DOI：
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发表时间：
1962
期刊：
影响因子：
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作者：
S. S. Hakim;J. Higham
通讯作者：
J. Higham
DOI：
--
发表时间：
2001
期刊：
影响因子：
--
作者：
H. Pleiner;E. Jarkova;H. Müller;H. Brand
通讯作者：
H. Brand
DOI：
--
发表时间：
1997
期刊：
影响因子：
--
作者：
G. Rikken;B. Tiggelen
通讯作者：
B. Tiggelen
铁磁流体结构转变理论：链和“气-液”相变。
DOI：
--
发表时间：
2002
期刊：
Physical review. E, Statistical, nonlinear, and soft matter physics
影响因子：
--
作者：
A. Zubarev;L. Iskakova
通讯作者：
L. Iskakova
铁磁流体动力学模拟：刚性偶极子模型与具有内部自由度的粒子
DOI：
--
发表时间：
2007
期刊：
影响因子：
--
作者：
D. Berkov;N. Gorn;D. Stock
通讯作者：
D. Stock