Molecular free path distribution in rarefied gases

Nishanth Dongari, Yonghao Zhang, Jason Reese

Research output: Contribution to journalArticlepeer-review

48 Citations (Scopus)
146 Downloads (Pure)


We present the results of investigations into the distribution of molecular free paths in rarefied gases using molecular dynamics simulations. Our tests on a range of different gas densities and confinements (unbounded, single bounding wall and parallel bounding walls) indicate that the molecules perform Lévy-type flights, irrespective of the presence of a bounding wall. The free paths most closely follow a power-law distribution. Simulations of gases confined by planar surfaces indicate that the local molecular mean free path varies sharply close to a solid surface. These results may yield new insight into diffusive transport in rarefied gases, in particular, the constitutive behaviour of gas flows in micro- and nanoscale devices.
Original languageEnglish
Pages (from-to)Article 125502
Number of pages6
JournalJournal of Physics D: Applied Physics
Issue number12
Publication statusPublished - 30 Mar 2011


  • molecular free paths
  • rarefied gases
  • molecular dynamics simulations
  • gas flows in micro and nanoscale devices


Dive into the research topics of 'Molecular free path distribution in rarefied gases'. Together they form a unique fingerprint.

Cite this