A Study on an Analysis of Non-equilibrium of Rotational Temperatures in Supersonic Free Molecular Flows by REMPI.

Bibliographic Information

Other Title
  • REMPIによる超音速自由分子流における回転温度非平衡現象の解析に関する研究
  • REMPI ニ ヨル チョウオンソク ジユウ ブンシリュウ ニ オケル カイテン オンド ヒヘイコウ ゲンショウ ノ カイセキ ニ カンスル ケンキュウ

Search this article


In highly rarefied gas flows, there appear nonequilibrium phenomena not only between translational and rotational energy modes (non-equipartition) but also deviation of rotational energy distribution from the Boltzmann distribution. To analyze these highly rarefied gas flows, we established the experimental system for 2R+2 N2-REMPI and applied it to the measurement of rotational temperature in a supersonic free molecular flow of nitrogen. In this study, a strong nonequilibrium in rotational energy mode has been found in a nitrogen free molecular flow. The data in the Boltzmann plot, obtained from the measured REMPI spectra, cannot be fitted by one line but approximately by two lines, revealing the non-Boltzmann distribution of rotational energy in the ground state. The mechanism of the deviation from the Boltzmann distribution is also discussed using the state-to-state transition rates for collisional relaxation.


Citations (3)*help

See more


See more


Report a problem

Back to top