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Achievement of Enhanced Fuel Economy via i-VTEC Intake Valve Closure Delay Mechanism

Article of Honda R&D Technical Review Vol.18 No.1

Summary

The conventional VTEC system has been modified with a mechanism enabling delayed closure of the intake valves as a new method of increasing fuel economy. The major characteristic of the new engine is the achievement of a balance between low fuel consumption and high power by means of switching between a delayed closure cam with delayed intake valve closure timing and a high output cam, depending on engine load. The intake valve closure delay mechanism employs the delayed closure cam when the engine is under low load in order to reduce pumping loss. The high output cam is employed when the engine is under high load, in order to produce high power. A variety of driving conditions were considered and in-cylinder flow simulations were used in setting the valve timing of the delayed closure cam. The delayed closure cam achieves a 6% reduction in engine fuel consumption compared to the high output cam. The application of the new VTEC mechanism has enabled the achievement of 17.0 km/L fuel economy in the Japanese 10-15 mode, representing a 5% increase on the level as stipulated by domestic 2010 fuel economy standards.

Reference

(1) Kohda, Y., Suganami, T., Kobayashi, H., Ogawa, K.: Development of High-performance and Low-emission Direct Injection Gasoline Engine, Honda R&D Technical Review, Vol. 16, No. 1, p. 39-46 (2004)
(2) Niizato, T., Hayashi, A.: Development of new 2.0L Leanburn Engine, HONDA R&D Technical Review, Vol. 12, No. 2, p. 45-54 (2000)
(3) Noguchi, K., Fujiwara, M., Segawa, M., Sawamura, K., Suzuki, S.: Development of V6 i-VTEC Engine with Variable Cylinder Management, Honda R&D Technical Review, Vol. 16, No. 1, p. 85-92 (2004)
(4) Heywood, J. B.: Internal Combustion Engine Fundamentals, McGraw-Hill Book, p. 183-186 (1979)
(5) Yamana, K., Yuzawa, Y., Shiga, S., Nishida, K., Araki, M., Nakamura, H., Obokata, T.: Effect of Promoting the Intake Turbulence and Lean Burn on the Performance of Over-Expansion Cycle Gasoline Engine with Late Closing of Intake Valves, 2004 JSAE Annual Congress Proceedings, No. 95-04, p. 1-5
(6) Matsuoka, S.: A Few Comments on thermal Efficiency of Reciprocating I.C Engine, Internal combustion engine, Vol. 23, No. 4, p. 9-26 (1984)
(7) Hatamura, K., Goto, T., Choshi, M., Shimizu, H., Abe, H.: Development of Miller Cycle Gasoline Engine, 1993 JSAE Annual Congress Proceedings, No. 931, p. 201-204 (1993)
(8) Takaoka, T., Hirose, K., Ueda, T., Nouno, Y., Tada, H., Kanai, H.: A High Expansion Ratio Gasoline Engine for the TOYOTA Hybrid System, TOYOTA Technical Review, Vol. 47, No. 2, p. 56-63 (1997)
(9) Seko, K., Taga, W., Torii, K., Nakamura, S., Akima, K., Sekiya, N.: Development of 1.8L i-VTEC Gasoline Engine for 2006 Model Year Honda CIVIC, Honda R&D Technical Review, Vol. 18, No. 1, p. 8-15 (2006)
(10) Heywood, J. B.: Internal Combustion Engine Fundamentals, McGraw-Hill Book, p. 715 (1979)
(11) Nagumo, S., Hara, S.: Study of Fuel Economy Improvement Through Control of Intake Valve Closing Timing -Cause of Combustion Deterioration and Improvement of Combustion-, Transactions of Society of Automotive Engineers of Japan, Vol. 26, No. 4, p. 17-23 (1995)

Author (organization or company)

Kazuyuki SEKO(Tochigi R&D Center)、Aruto HAYASHI(Tochigi R&D Center)、Masahiro NAKAJIMA (Tochigi R&D Center)

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