Dolinsky Yu, Elperin T
The Pearlstone Center for Aeronautical Engineering Studies, Department of Mechanical Engineering, Ben-Gurion University of the Negev, P. O. B. 653, Beer-Sheva 84105, Israel.
Phys Rev E Stat Nonlin Soft Matter Phys. 2006 Jun;73(6 Pt 2):066607. doi: 10.1103/PhysRevE.73.066607. Epub 2006 Jun 7.
We study a system comprising a spheroidal particle with permittivity epsilon 2 and conductivity sigma 2 immersed in a host medium with permittivity epsilon 1 and conductivity sigma 1 in the ac external electric field with a strength Epsilon 0 and frequency omega. We determined conditions when orientation of a spheroidal particle with a finite electric conductivity at t --> infinity coincides with the orientation of the ideal dielectric spheroidal particle, when orientation of a spheroid at t --> infinity is normal to the orientation of the ideal dielectric spheroidal particle, and when orientation of particle is not affected by the external electric field. We found the direct connection between the final orientation of the particle and the existence of two time intervals, T1(omega) and T2(omega), such that during time interval T1 an equilibrium orientation of the particle is the same as the equilibrium orientation of an ideal dielectric particle while during time interval T2 the direction of the stable equilibrium orientation is normal to the equilibrium orientation of an ideal dielectric particle. The values T1 and T2 depend on the frequency of the external field omega and T = T1(omega) + T2(omega), where T=2 pi/omega.
我们研究了一个系统，该系统包含一个介电常数为ε₂、电导率为σ₂的球形颗粒，它浸没在一个介电常数为ε₁、电导率为σ₁的主体介质中，并处于强度为ε₀、频率为ω的交流外部电场中。我们确定了在t→∞时，具有有限电导率的球形颗粒的取向与理想介电球形颗粒的取向一致的条件，球形颗粒在t→∞时的取向与理想介电球形颗粒的取向垂直的条件，以及颗粒取向不受外部电场影响的条件。我们发现了颗粒的最终取向与两个时间间隔T₁(ω)和T₂(ω)的存在之间的直接联系，使得在时间间隔T₁内，颗粒的平衡取向与理想介电颗粒的平衡取向相同，而在时间间隔T₂内，稳定平衡取向的方向与理想介电颗粒的平衡取向垂直。T₁和T₂的值取决于外部场的频率ω，且T = T₁(ω) + T₂(ω)，其中T = 2π/ω。
