1. Home
  2. Honda R&D Technical Review Vol.18 N...
  3. CFD Air Flow Analysis for Air-coole...

Technical Review e-Book: Summary

CFD Air Flow Analysis for Air-cooled of Motorcycle Engines

Article of Honda R&D Technical Review Vol.18 No.2


In order to develop an air-cooled engine, cooling air flow was analyzed by CFD (Computational Fluid Dynamics). Cooling performance of engine is necessary for precise temperature control. However, stable radiation is difficult for motorcycles because of the driving wind. Cooling fins are thin and complicated; therefore plenty of work time is necessary to create a boundary fitted mesh. In addition, since low Reynolds (Re) number area coexists with high Re number area in a calculation domain, applications of the wall function are limited. Therefore, we employed the Partial Cells in Cartesian coordinate method, which expresses complex shapes according to turbulence boundary conditions in the Cartesian coordinate. Analysis results showed good agreement with wind tunnel test results. Furthermore, useful knowledge in engine developments was obtained by examinations of local heat transfer coefficients calculated by Karman’s analogy.


(1) Takahashi, Y., Fukuzawa, K., Fujii, I.: Numerical simulation of flow in intake ports and cylinder of multi-valve S.I. engine using PCC method, Proceedings of International Symposium on COMODIA 94, p. 529-534 (1994)
(2) Takahashi, Y., Nomura, T., Ishima, T., Obokata, T.: Numerical analysis on steady state in-cylinder-flow by Partial Cells in Cartesian Coordinate method and verification with PIV measurement, Transactions of the Japan Society of Mechanical Engineers, Vol. 71, No. 706, B (2005-6), p. 1694-1701 (2005)
(3) 3DataExpert, http://www.deskartes.com, 2006/1/16
(4) Tachibana, F., Akiyama, M., Okamoto, Y., Morishita, T.: Fundamentals of Heat transmission, Corona Publishing Co., Ltd., p. 44 (1965)

Author (organization or company)

Yasushi TAKAHASHI(Motorcycle R&D Center)、Yoshitsugu GOKAN(Motorcycle R&D Center)

We would like to get your opinion on this research paper. (This is only applicable to registered members.)

The readers of this research paper have also selected these research papers.

Development Methodologies for Formula One Aerodynamics
Article of Honda R&D Technical Review F1 Special (The third Era Activities)
CFD Technology for Formula One Engine
Article of Honda R&D Technical Review F1 Special (The third Era Activities)
Development of Variable Cooling System Aimed at Fuel Economy Improvement of Air-cooled Engine for Scooters
Article of Honda R&D Technical Review Vol.30 No.1