An availability analysis of dual-fuel engines at part loads: The effects of pilot fuel quantity on availability terms

Abstract

It is well known that dual-fuel engines at part load inevitably suffer from lower thermal efficiency and higher emission of carbon monoxide and unburned fuel. A quasi-two-zone combustion model has been developed for studying the second-law analysis of a dual-fuel (diesel-gas) engine operating under part load conditions. This quasi-two-zone combustion model is able to establish the development of combustion process with time and associated important operating parameters, such as pressure, temperature, heat release rate, and species concentration. The present study is an attempt to investigate the combustion phenomenon from the second law point of view at part load and increasing pilot fuel quantity is considered to improve the above-mentioned problems. By employing different quantities of pilot fuel, it is found that increasing the pilot fuel quantity increases the work availability and reduces chemical availability of unburned fuels. Also, the results indicate that, compared to the baseline dual-fuel engine, increasing the pilot fuel quantity in about 12 per cent results in an increase of 23 per cent in availability destruction and 29 per cent in the second law efficiency. This enhancement is due to a better combustion progress and increased indicated work when a high amount of pilot fuel quantity is employed.

Keywords

availability analysis quasi-two-zone combustion model chemical kinetics dual-fuel engine second-law efficiency pilot fuel

Get full access to this article

View all access options for this article.

References

Pirouzpanah

Khoshbakhti Saray

, ‘Enhancement of the combustion process in dual-fuel engines at part loads using exhaust gas recirculation’ Proc. IMechE, Part D: J. Automobile Engineering 221 D7 (2007): 877–888. DOI: 10.1243/09544070JAUTO389.

Alkidas

A. C.

, ‘The application of availability and energy balances to a diesel engine’ Trans ASME, J. Eng. Gas Turbines Power 110 (1988): 462–469.

Moran

M. J.

, Availability analysis: A guide to efficient energy use (NJ: Prentice-Hall 1982).

Rakopoulos

C. D.

Michos

C. N.

Giakoumis

E. G.

, ‘Availability analysis of a syngas fueled spark ignition engine using a multi-zone combustion model’ Energy 33 (2008): 1378–1398.

Caton

J. A.

, ‘A review of investigations using the second-law of thermodynamics to study internal-combustion engines’ (2001): SAE paper 2000–01–1081.

Rakopoulos

C. D.

Giakoumis

E. G.

, ‘Simulation and exergy analysis of transient diesel engine operation’ Energy 22 (1997): 875–885.

Caton

J. A.

, ‘On the destruction of availability (exergy) due to combustion processes—with specific application to internal combustion engines’ Energy 25 (2000): 1097–1117.

Rakopoulos

C. D.

Giakoumis

E. G.

, ‘Development of cumulative and availability rate balances in a multi-cylinder turbocharged IDI diesel engine’ Energy Convers. Manage. 38 (1997): 347–369.

Kyritsis

D. C.

Rakopoulos

C. D.

, ‘Parametric study of the availability balance in an internal combustion engine cylinder’ (2001): SAE paper 2001-01-1263.

10.

Van Gerpen

J. H.

Shapiro

H. N.

, ‘Second-law analysis of diesel engine combustion’ Trans ASME, J Eng. Gas Turbines Power 112 (1990): 129–137.

11.

Rakopoulos

C. D.

Kyritsis

D. C.

, ‘Comparative second-law analysis of internal combustion engine operation for methane, methanol and dodecane fuels’ Energy 26 (2001): 705–722.

12.

Rakopoulos

C. D.

Kyritsis

D. C.

, ‘The influence of cylinder wall temperature profile on the second-law diesel engine transient response’ Appl. Therm. Eng. 25 (2005): 1779–1795.

13.

Rakopoulos

C. D.

Kyritsis

D. C.

, ‘Hydrogen enrichment effects on the second-law analysis of natural and landfill gas in engine cylinders’ Hydrog. Energy 31 (2006): 1384–1393.

14.

Chavannavar

P. S.

Caton

J. A.

, ‘Destruction of availability (exergy) due to combustion processes: A parametric study’ Proc. IMechE, Part A: J. Power Energy 220 A7 (2006): 655–669. DOI: 10.1243/09576509JPE267.

15.

Rakopoulos

C. D.

Michos

C. N.

, ‘Development and validation of a multi-zone combustion model for performance and nitric oxide formation in syngas fueled spark ignition engine’ Energy Convers. Manage. 49 (2008): 2924–2938.

16.

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 Convers. Manage. 42 (2001): 1477–1498.

17.

Miyamoto

Chikahisa

Murayama

Sawyer

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

18.

Annand

W. J. D.

, ‘Heat transfer in the cylinders of reciprocating internal combustion engine’ Proc. Inst. Mech. Engrs. 177 (1963): 973–980.

19.

, Applied thermodynamics: Availability method and energy conversion (New York: McGraw-Hill 1995).

20.

Rakopoulos

C. D.

Giakoumis

E. G.

, ‘Second-law analyses applied to internal combustion engines operation’ Prog. Energy Combust. Sci. 32 (2006): 2–47.

21.

Pirouzpanah

Mirsalim

S. M.

Jeyhooni

Afghahi

, ‘Reduction of pollutant emissions of OM-355 diesel engine to Euro2 by converting to dual-fuel engine (diesel + gas)’ In Proceedings of the First Conference on Conversion automotive fuel to CNG, Tehran, Iran, 19–20 June 2003, pp. 84–94.