Investigation on the fuel injection quantity fluctuation of a common-rail fuel injection system using response surface methodology

Abstract

Variations in the parameters affect the injection characteristics of a common-rail injection system and leads to fluctuation in the fuel injection quantity. This paper is aimed at combining the numerical modelling and design of experiments to investigate the significant effects of the interactions between the common-rail injector parameters on the fluctuation in the fuel injection quantity using response surface methodology. A numerical model of a common-rail injector was developed. The model was validated by comparing simulation results with experimental measurements, which showed that it can accurately predict the fuel injection quantity of the system. The design of experiments was performed using a two-level five-factor D-optimal design. The factors studied were the pre-tension of the control valve spring, the diameter of the outlet orifice, the diameter of the inlet orifice, the needle lift and the diameter of the nozzle holes. A quadratic response surface model was suggested by means of partial least-squares regression analysis. The distribution of the standardized residuals, the relation between the predicted fluctuation and the observed fluctuation in the fuel injection quantity, the coefficient R² of determination and the adjusted coefficient $R_{adj}^{2}$ of determination for the response surface model were analysed, which demonstrated the significance of the model. Analysis of the F value and the p value for the model terms at the 95% confidence level revealed that the interactions between the control valve spring pre-tension and the nozzle hole diameter, between the outlet orifice diameter and the nozzle hole diameter, between the inlet orifice diameter and the nozzle hole diameter and between the needle lift and the nozzle hole diameter had significant effects on the fluctuation in the fuel injection quantity of the system. Furthermore, the significant effects of the interactions between these parameters were analysed in detail.

Keywords

Common-rail injection system fuel injection quantity fluctuation response surface methodology interactive effect

Get full access to this article

View all access options for this article.

References

Braun

Rabl

Mayer

. Emission reduction potential by means of high boost and injection pressure at low- and mid-load for a common rail diesel engine under high EGR rates. SAE paper 2013-01-2541, 2013.

Gupta

Zhang

Sun

. Modeling and control of a novel pressure regulation mechanism for common rail fuel injection systems. Appl Mathl Modelling 2011; 35: 3473–3483.

Nikzadfar

Shamekhi

. Investigating the relative contribution of operational parameters on performance and emissions of a common-rail diesel engine using neural network. Fuel 2014; 125: 116–128.

Salvador

Gimeno

Morena

. Using one-dimensional modeling to analyze the influence of the use of biodiesels on the dynamic behavior of solenoid-operated injectors in common rail systems: results of the simulations and discussion. Energy Conversion Managmt 2012; 54: 122–132.

Hirkude

Padalkar

. Performance optimization of CI engine fuelled with waste fried oil methyl ester–diesel blend using response surface methodology. Fuel 2014; 119: 266–273.

Saidur

Jahirul

Hasanuzzaman

. Analysis of exhaust emissions of natural gas engine by using response surface methodology. J Appl Sci 2008; 8: 3328–3339.

Dhole

Yarasu

Lata

. Mathematical modeling for the performance and emission parameters of dual fuel diesel engine using hydrogen as secondary fuel. Int J Hydrogen Energy 2014; 39: 12991–13001.

Perez

Boehman

. Performance of a single-cylinder diesel engine using oxygen-enriched intake air at simulated high-altitude conditions. Aerospace Sci Technol 2010; 14: 83–94.

Pandian

Sivapirakasam

Udayakumar

. Investigation on the effect of injection system parameters on performance and emission characteristics of a twin cylinder compression ignition direct injection engine fuelled with pongamia biodiesel–diesel blend using response surface methodology. Appl Energy 2011; 88: 2663–2676.

10.

Montgomery

Reitz

. Optimization of heavy-duty diesel engine operating parameters using a response surface method. SAE paper 2000-01-1962, 2000.

11.

Win

Gakkhar

Jain

. Investigation of diesel engine operating and injection system parameters for low noise, emissions, and fuel consumption using Taguchi methods. Proc IMechE Part D: J Automobile Engineering 2005; 219(10): 1237–1251.

12.

Lino

Maione

Rizzo

. Nonlinear modeling and control of a common rail injection system for diesel engines. Appl Mathl Modelling 2007; 31: 1770–1784.

13.

Han

Duan

Wang

. Experimental study on injection characteristics of fatty acid esters on a diesel engine common rail system. Fuel 2014; 123: 19–25.

14.

Payri

Salvador

Martí-Aldaraví

. Using one-dimensional modeling to analyze the influence of the use of biodiesels on the dynamic behavior of solenoid-operated injectors in common rail systems: detailed injection system model. Energy Conversion Managmt 2012; 54: 90–99.

15.

Chung

Sunwoo

. Modelling and injection rate estimation of common-rail injector for direct-injection diesel engines. Proc IMechE Part D: Automobile Engineering 2008; 222(6): 1089–1001.

16.

Coppo

Dongiovanni

. Experimental validation of a common-rail injector model in the whole operation field. Trans ASME, J Engng Gas Turbines Power 2007; 129: 596–608.

17.

Frédéric

Patrice

. Impact of physical properties of biodiesel on the injection process in a common-rail direct injection system. Energy Conversion Managmt 2009; 50: 2905–2912.

18.

Francisco

Alejandro

Jaime

. Complete modelling of a piezo actuator last-generation injector for diesel injection systems. Int J Engine Res 2014; 15: 3–19.

19.

Payri

Climent

Salador

. Diesel injection system modelling. Methodology and application for a first-generation common rail system. Proc IMechE Part D: Automobile Engineering 2004; 218(1): 81–91.

20.

Hernández

Sanz-Argent

Carot

. Modelling of the auto-ignition angle in diesel HCCI engines through D-optimal design. Fuel 2010; 89: 2561–2568.

21.

Myers

Montgomery

Anderson-Cook

. Response surface methodology: process and product optimization using designed experiments. 3rd edition. Hoboken, New Jersey: John Wiley, 2009, pp.1–10.

22.

Huang

Xie

. Optimization of nutrient component for diesel oil degradation by Acinetobacter beijerinckii ZRS. Mar Pollution Bull 2013; 76: 325–332.