Direct heat loss to combustion chamber walls in a direct-injection diesel engine: Evaluation of direct heat loss to piston and cylinder head

Abstract

The purpose of this study is to clarify the state of the heat loss in a direct-injection diesel engine. Originally developed thin-film thermocouples (TFTs) are embedded into the combustion chamber walls for accurate measurement of instantaneous surface temperature from which instantaneous heat flux is evaluated through the heat conduction equation. Measured points are arrayed on the cavity bottom, the cavity side wall, the piston top, and the cylinder head. The TFTs are designed and fabricated so that disturbance of the temperature field is minimized when they are embedded into the combustion chamber walls. As a result, it is observed that the behaviour of instantaneous temperature and heat flux depends on the radius of the measured point. Measured points located radially inwards seem to be influenced by the combustion flame considerably more than those located outwards because the flame is presumed to stay in and around the cavity which occupies a region around the central axis of the piston. On the other hand, the heat loss ratio, namely the ratio of lost heat to the heat supplied by the fuel, is larger than in a gasoline engine.

Keywords

diesel engine thermal efficiency thin-film thermocouple instantaneous surface temperature instantaneous heat flux

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References

Hara

Oguri

Periodic heat transfer in internal combustion engines: Measurement of piston temperature of spark-induced engine (in Japanese with English summary)

Trans. Jap. Soc. Mech. Engrs, 1958, 24(148), 991–998.

Overbye

V. D.

Bennethum

J. E.

Uyehara

O. A.

Myers

P. S.

Unsteady heat transfer in engines

SAE Trans., 1961, 461–494.

LeFeuvre

Myers

P. S.

Uyehara

O. A.

Experimental instantaneous heat fluxes in a diesel engine and their correlation. SAE paper 690464, 1969, pp. 1–21.

Hohenberg

G. F.

Advanced approaches for heat transfer calculations. SAE paper 790825, 1979, pp. 61–69.

Enomoto

Ohya

Ishii

Enomoto

Kitahara

Study on analysis of instantaneous heat flux flowing into the combustion chamber wall of an internal combustion engine: Examination in the case of consideration of heat storage term and the temperature dependency of the thermocouple's thermophysical properties

Int. J. Jap. Soc. Mech. Engrs, Ser. II, 1992, 35(4), 608–615.

Yamada

Emi

Ishii

Suzuki

Kimura

Enomoto

Heat loss to the combustion chamber wall with deposit in D.I. diesel engine: Variation of instantaneous heat flux on piston surface with deposit

Jap. Soc. Automot. Engrs Rev., 2002, 23, 415–421.

Yoshida

Harigaya

Nishida

Heat flow on the each combustion chamber walls of pre-combustion chamber type diesel engine: Heat flow on the piston surface (in Japanese)

Trans. Jap. Soc. Mech. Engrs, 1979, 45(391), 416–425.

Enomoto

Furuhama

Study on thin film thermocouple for measuring instantaneous temperature on surface of combustion chamber wall in internal combustion engine

Bull. Jap. Soc. Mech. Engrs, 1985, 28(235), 108–116.

Enomoto

Furuhama

Study on thin film thermocouple for measuring instantaneous temperature on surface of combustion chamber wall in internal combustion engine: Study on thin film thermocouples embedded in combustion chamber wall

Bull. Jap. Soc. Mech. Engrs, 1986, 29(256), 3434–3441.

10.

Enomoto

Furuhama

Minakami

Heat loss to combustion chamber wall of 4-stroke gasoline engine: Heat loss to piston cylinder

Bull. Jap. Soc. Mech. Engrs, 1985, 28(238), 647–655.

11.

Enomoto

Furuhama

Heat loss to combustion chamber wall of 4-stroke gasoline engine: Heat loss into cylinder head, intake and exhaust valves

Bull. Jap. Soc. Mech. Engrs, 1986, 29(253), 2196–2203.

12.

Enomoto

Furuhama

Heat transfer to wall of ceramic combustion chamber of internal combustion engine

Bull. Jap. Soc. Mech. Engrs, 1986, 29(250), 1211–1217.

13.

Furuhama

Enomoto

Heat transfer into ceramic combustion wall of internal combustion engines. SAE paper 870153, 1987, pp. 109–124.

14.

Kimura

Matsui

Koike

Enomoto

Study of heat rejection mechanism of a direct-injection diesel engine: Characteristics of local heat flux (in Japanese with English summary)

Trans. Jap. Soc. Mech. Engrs, 1997, 63(613), 3187–3193.

15.

Kimura

Matsui

Koike

Enomoto

Study of heat rejection mechanism of a direct-injection diesel engine: Effects of combustion control item on heat flux (in Japanese with English summary)

Trans. Jap. Soc. Mech. Engrs, 1997, 63(613), 3194–3199.

16.

Uchimi

Taya

Hagihara

Kimura

Enomoto

Heat loss to combustion chamber wall in a D.I. diesel engine: Tendency of heat loss to piston surface

Jap. Soc. Automot. Engrs Rev., 2000, 21, 133–135.

17.

Adachi

Hagihara

Nagano

Ishii

Enomoto

Study on improvement of accuracy in analysis of instantaneous heat flux flowing into ceramic combustion chamber wall surface: Examination in the conversion method from thermo electromotive force to temperature (in Japanese with English summary)

Proc. Jap. Soc. Mech. Engrs, Ser. III, 1997, 97(1), 41–42.