Physics – Condensed Matter – Statistical Mechanics
Scientific paper
2012-02-22
Phys. Rev. E 85, 041303 (2012)
Physics
Condensed Matter
Statistical Mechanics
4 figures; to be published in Phys. Rev. E
Scientific paper
10.1103/PhysRevE.85.041303
An intriguing phenomenon displayed by granular flows and predicted by kinetic-theory-based models is the instability known as particle "clustering," which refers to the tendency of dissipative grains to form transient, loose regions of relatively high concentration. In this work, we assess a modified-Sonine approximation recently proposed [Garz\'o et al., Physica A 376, 94 (2007)] for a granular gas via an examination of system stability. In particular, we determine the critical length scale associated with the onset of two types of instabilities -vortices and clusters- via stability analyses of the Navier-Stokes-order hydrodynamic equations by using the expressions of the transport coefficients obtained from both the standard and the modified-Sonine approximations. We examine the impact of both Sonine approximations over a range of solids fraction \phi <0.2 for small restitution coefficients e=0.25--0.4, where the standard and modified theories exhibit discrepancies. The theoretical predictions for the critical length scales are compared to molecular dynamics (MD) simulations, of which a small percentage were not considered due to inelastic collapse. Results show excellent quantitative agreement between MD and the modified-Sonine theory, while the standard theory loses accuracy for this highly dissipative parameter space. The modified theory also remedies a (highdissipation) qualitative mismatch between the standard theory and MD for the instability that forms more readily. Furthermore, the evolution of cluster size is briefly examined via MD, indicating that domain-size clusters may remain stable or halve in size, depending on system parameters.
Ewasko Christopher J.
Garzo Vicente
Hilger Andrew M.
Hrenya Christine M.
Mitrano Peter P.
No associations
LandOfFree
Assessing a Hydrodynamic Description for Instabilities in Highly Dissipative, Freely Cooling Granular Gases does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Assessing a Hydrodynamic Description for Instabilities in Highly Dissipative, Freely Cooling Granular Gases, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Assessing a Hydrodynamic Description for Instabilities in Highly Dissipative, Freely Cooling Granular Gases will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-415739