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10:03
The Preparation of Electrohydrodynamic Bridges from Polar Dielectric Liquids
Published on: September 30, 2014
Hamiltonian field theory of ferrohydrodynamics
B U Felderhof1, V V Sokolov, P A Éminov
1Institut für Theoretische Physik A, RWTH Aachen University, Templergraben 55, 52056 Aachen, Germany. ufelder@physik.rwth-aachen.de
The Journal of Chemical Physics
|October 21, 2011
Summary
This study presents a Hamiltonian field theory for ferrohydrodynamics, incorporating dissipation. It reveals flexibility in constructing dynamical equations for fluid properties and magnetization dynamics, characterized by two coefficients.
Area of Science:
- Physics
- Fluid Dynamics
- Magnetohydrodynamics
Background:
- Ferrohydrodynamics describes the behavior of magnetic fluids.
- Existing models may lack comprehensive descriptions of dissipative effects and magnetization dynamics.
Purpose of the Study:
- To derive a Hamiltonian field theory for ferrohydrodynamics.
- To incorporate dissipative effects using a Rayleigh dissipation function.
- To analyze the implications of kinematic assumptions on magnetization behavior.
Main Methods:
- Derivation of a Hamiltonian field theory.
- Inclusion of dissipation via a Rayleigh dissipation function.
- Analysis of kinematic assumptions on fluid element displacements.
Main Results:
- A Hamiltonian field theory for ferrohydrodynamics with dissipation is established.
- Kinematic assumptions allow freedom in constructing dynamical equations for mass density, flow velocity, entropy density, magnetization, and spin density.
- The convective behavior of magnetization is quantified by two dimensionless coefficients.
Conclusions:
- The derived theory provides a robust framework for studying ferrohydrodynamics.
- The identified freedom in dynamical equations highlights the importance of specific kinematic assumptions.
- The dimensionless coefficients offer a means to characterize magnetization convection.
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