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Communication: On the diffusion tensor in macroscopic theory of cavitation
1Department of Physics, New Jersey Institute of Technology, Newark, New Jersey 07102, USA.
The Journal of Chemical Physics
|August 17, 2017
Summary
This study introduces a generalized Fokker-Planck equation (FPE) for describing bubble nucleation in fluids. It enables accurate modeling across all parameter domains, advancing cavitation and fluid dynamics research.
Area of Science:
- Fluid dynamics
- Thermodynamics
- Statistical mechanics
Background:
- Classical nucleation theory uses a 1D Fokker-Planck equation (FPE) for bubble size.
- This approach is limited to the critical nucleus vicinity when additional variables are involved.
Purpose of the Study:
- To develop a generalized FPE applicable to a wider range of parameters for bubble nucleation.
- To construct complete FPEs for viscous volatile and inertial fluids.
Main Methods:
- Selection of "proper" kinetic variables to define the diffusion tensor D^ across all parameter domains.
- Numerical solution of the FPE for viscous volatile fluids.
- Consideration of an equivalent Langevin equation for inertial fluids.
Main Results:
- Complete FPEs are constructed for viscous volatile and inertial fluids.
- Numerical and analytical results for both fluid types are obtained and compared.
- The generalized approach is shown to be valid beyond the immediate vicinity of the critical nucleus.
Conclusions:
- The developed method allows for a comprehensive description of bubble nucleation.
- This generalized FPE approach offers a powerful tool for studying phase transitions in fluids.
- The methodology is broadly applicable to various physical phenomena beyond cavitation.
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