Hokkaido University Research Profiles

Manufacturing Technology

New Developments in Combustion Reaction Fluid Simulation

Proposal of a highly efficient analysis method that enables the application of detailed reaction mechanisms

We are proposing a numerical analysis technique to efficiently incorporate detailed large-scale reaction mechanisms, such as those of hydrocarbon fuels that consist of hundreds of chemical species and thousands of chemical reaction orders, into thermo-fluid simulations.

Content of research

Until now, chemical reaction phenomena in thermo-fluid (CFD) analysis have been modeled simply by assuming an infinitely fast reaction or an overall reaction model consisting of a few chemical species and reaction equations due to computational load and lack of analysis techniques. On the other hand, when the interaction between chemical reactions and fluid phenomena is important, such as in the case of unsteady phenomenon prediction like the ignition timing of automobile engines or ultra-dilute combustion under extreme conditions, it is difficult to apply simple models. Our research group has solved the problem of applying detailed reaction mechanisms to CFD analysis. The proposed method consists of a time integration method (ERENA) that can significantly reduce the calculation time of chemical reaction equations, and a species bundling technique that combines similar chemical species. Depending on the conditions, the proposed method can be tens to hundreds of times faster than the conventionally used methods while maintaining equivalent accuracy.

  • Example of hydrazine coaxial jet flame analysis by detailed reaction mechanism/fluid analysis

Potential for social implementation

  • ・燃焼流れ全般
  • ・自動車エンジンのノッキング現象
  • ・液体ロケットエンジン燃焼流れ
  • ・宇宙機衛星ヒドラジン燃焼流れ
  • ・General combustion flow
  • ・Knocking phenomena of automobile engines
  • ・Liquid rocket engine combustion flow
  • ・Spacecraft satellite hydrazine combustion flow
  • ・Spontaneous ignition phenomenon of high pressure tank hydrogen leak

Appealing points to industry and local governments

We are promoting the integration of detailed chemical reaction mechanisms and CFD analysis, which has been difficult in the past, and are continuing to develop techniques and apply them. We hope that this analysis technology will be useful to understand phenomena and develop designs. Some of the analysis techniques are provided as program subroutines and can be used by anyone.