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Updated: Aug 6, 2026
11:03
An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Inelastic processes in state-resolved transport theory: Application to oxygen mixtures
1St Petersburg University, 7-9 Universitetskaya Embankment, St Petersburg 199034, Russia.
The Journal of Chemical Physics
|July 22, 2026
Summary
A new Variable Hard Sphere Statistical Inelastic Cross Section (VHS-SICS) model accurately predicts transport properties in nonequilibrium flows. This model enhances state-to-state calculations by incorporating rotational and vibrational effects for improved accuracy.
Area of Science:
- Fluid dynamics
- Chemical physics
- Computational chemistry
Background:
- Accurate prediction of transport properties in strongly nonequilibrium flows is crucial.
- State-to-state approaches require reliable state-resolved collision integrals.
Purpose of the Study:
- To develop a self-consistent Variable Hard Sphere Statistical Inelastic Cross Section (VHS-SICS) model.
- To accurately predict transport properties in nonequilibrium oxygen-containing flows.
Main Methods:
- Constructed a unified analytical framework for elastic and rotationally inelastic cross sections.
- Incorporated vibrationally inelastic cross sections using the forced harmonic oscillator with free rotation model.
- Determined VHS parameters by fitting to quasiclassical trajectory reference data.
Main Results:
- The VHS-SICS model showed good agreement with reference data over a wide temperature range.
- Rotationally inelastic effects significantly increase with temperature and vibrational excitation.
- Rotationally inelastic effects reduce shear viscosity and thermal conductivity in O2/O mixtures.
Conclusions:
- The VHS-SICS model provides a reliable framework for predicting transport properties in nonequilibrium flows.
- Rotationally inelastic collisions play a significant role in the transport properties of O2/O mixtures.
- Vibrational inelasticity has a negligible impact on collision integrals in the studied temperature range.
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