Enhancement of the combustion process in dual-fuel engines at part loads using exhaust gas recirculation

Abstract

Dual-fuel engines at part loads inevitably suffer from lower thermal efficiency and higher carbon monoxide and unburned fuel emission. The present work was carried out to investigate the combustion characteristics of a dual-fuel (diesel-gas) engine at part loads, using a single-zone combustion model with detailed chemical kinetics for combustion of natural gas fuel. The authors have developed software in which the pilot fuel is considered as a subsidiary zone and a heat source derived from two superimposedWiebe combustion functions to account for its contribution to ignition of the gaseous fuel and the rest of the total released energy. The chemical kinetics mechanism consists of 112 reactions with 34 species. This quasi-two-zone combustion model is able to establish the development of the combustion process with time and the associated important operating parameters, such as pressure, temperature, heat release rate (HRR), and species concentration. Therefore, this paper describes an attempt to investigate the combustion phenomenon at part loads and using hot exhaust gas recirculation (EGR) to improve the above-mentioned drawbacks and problems. By employing this technique, it is found that lower percentages of EGR and allowance for its thermal and radical effects have a positive influence on performance and emission parameters of dual-fuel engines at part loads. Predicted values show good agreement with corresponding experimental values under special engine operating conditions (quarter-load, 1400 r/min). Implications are discussed in detail.

Keywords

quasi-two-zone combustion model chemical kinetics natural gas dual-fuel engines exhaust gas recirculation

Get full access to this article

View all access options for this article.

References

Karim

G. A.

Liu

A predictive model for knock in dual fuel engines. Trans. SAE, 1992, SAE paper 921550.

Liu

Karim

G. A.

A predictive model for the combustion process in dual fuel engines. SAE paper 952435, 1995.

Pirouzpanah

Khoshbakhti Saray

Reduction of emissions in an automotive direct injection diesel engine dual-fuelled with natural gas by using variable exhaust gas recirculation. Proc. Instn Mech. Engrs, Part D: J. Automobile Engineering, 2003, 217, 719–725.

Daisho

Yaeo

Koseki

Kihara

Saito

Quiros

E. N.

Combustion and exhaust emission in a direct injection diesel engine dual fueled with natural gas. SAE paper 950465, 1995.

Karim

G. A.

Yan

Z. D.

Modeling of auto-ignition and knock in a compression ignition engine of the dual fuel type. IMechE Conference paper, 1991, C430/035, pp. 141–148.

Pirouzpanah

Kashani

B. O.

Prediction of major pollutants emission in direct-injection dual-fuel diesel and natural gas engines. SAE paper 1999–01-0841, 1999.

Abd Alla

G. H.

Soliman

H. A.

Badr

O. A.

Abd Rabbo

M. F.

Combustion quasi-two-zone predictive model for dual fuel engines. Energy Conversion and Managmt, 2001, 42, 1477–1498.

Abd Alla

G. H.

Soliman

H. A.

Badr

O. A.

Abd Rabbo

M. F.

A computational investigation of the effect of exhaust gas recirculation on the performance of a dual fuel engine. SAE paper 2000–01-2040, 2000.

Hountalas

D. T.

Papagiannakis

R. G.

Development of a simulation model for direct injection dual fuel diesel-natural gas engines. SAE paper 2000–01-0286, 2000.

10.

Hountalas

D. T.

Papagiannakis

R. G.

A simulation model for the combustion process of natural gas engines with pilot diesel fuel as an ignition source. SAE paper 2001–01-1245, 2001.

11.

Hountalas

D. T.

Papagiannakis

R. G.

Theoretical and experimental investigation of a direct injection dual fuel diesel - natural gas engine. SAE paper 2002–01-0868, 2002.

12.

Papagiannakis

R. G.

Hountalas

D. T.

Experimental investigation concerning the effect of natural gas percentage on performance and emissions of a DI dual fuel diesel engine. Appl. Thermal Engng, 2003, 23, 353–365.

13.

Hountalas

D. T.

Papagiannakis

R. G.

Combustion and exhaust emission characteristics of a dual fuel compression ignition engine operated with pilot diesel fuel and natural gas. Energy Conversion and Managmt, 2004, 45, 2971–2987.

14.

Liu

Karim

G. A.

Simulation of combustion processes in gas-fuelled diesel engines. Proc. Instn Mech. Engrs, Part A: J. Power and Energy, 1997, 211, 159–169.

15.

Mansour

Bounif

Aris

Gaillard

Gas—diesel (dual-fuel) modeling in diesel engine environment. Int. J. Therm. Sci., 2001, 40, 409–424.

16.

Pirouzpanah

Jafarmadar

Quasi-dimensional combustion model for predicting combustion and emission of dual fuel diesel engines. J. Fac. Engng, Univ. Tabriz, 2005, 31, 1–13.

17.

Kusaka

Okamoto

Daisho

Kihara

Saito

Combustion and exhaust gas emission characteristics of a diesel engine dual-fueled with natural gas. JSAE Rev., 2000, 21, 489–496.

18.

Mbarawa

Milton

B. E.

Casey

R. T.

Experiments and modelling of natural gas combustion ignited by a pilot diesel fuel spray. Int. J. Therm. Sci., 2001, 40, 927–936.

19.

Kusaka

Tsuzuki

K.-I.

Daisho

A numerical study on combustion and exhaust gas emissions characteristics of a dual fuel natural gas engine using a multi-dimensional model combined with detailed kinetics. SAE paper 2002–01-1750, 2002.

20.

Kusaka

Ito

Mizushima

Daisho

A numerical study on combustion and exhaust gas emissions formation processes of a dual fuel natural gas engine using a multi-dimensional model combined with detailed chemical kinetics. SAE paper 2003–01-1939, 2003.

21.

Singh

Kong

S. C.

Reitz

R. D.

Krishnan

S. R.

Midkiff

K. C.

Modeling and experiments of dual-fuel engine combustion and emissions. SAE paper 2004–01-0092, 2004.

22.

Karim

G. A.

Combustion in gas fueled compression: Ignition engines of the dual fuel type. J. Engng for Gas Turbines and Power, 2003, 125, 827–836.

23.

Miyamoto

Chikahisa

Murayama

Sawyer

Description and analysis of diesel engine rate of combustion and performance using Wiebe's functions. SAE paper 850107, 1985.

24.

Annand

W. J. D.

Heat transfer in the cylinders of reciprocating internal combustion engine. Proc. Instn Mech. Engrs, 1963, 177, 973–980.

25.

Pirouzpanah

Reduction of pollutants emissions of OM-355 diesel engine to Euro2 by converting to dual-fuel engine (diesel + gas). In Proceedings of 1st Conference on Conversion of Automotive Fuel to CNG, Tehran, Iran, 19–20 June 2003, pp. 84–94.