Skip to main content
SpringerLink
Log in

An analytical study on the performance analysis of a unit-injector system of a diesel engine

  • Published:
KSME International Journal Aims and scope Submit manuscript

Abstract

A numerical algorithm is developed to analyze the performance of a Unit-injector (UI) System for a diesel engine. The fundamental theory of the algorithm is based on the continuity equation of fluid dynamics. The loss factors that should be seriously regarded on the continuity equation are the compressibility effect of liquid fuel, the wall friction loss in high-pressure fuel lines of the system, the kinetic energy loss of fuel in the system, and the leakage of fuel out of the control volume. For an evaluation of the developed simulation algorithm, the calculation results are compared with the experimental outputs provided by the Technical Research Center of Doowon Precision Industry Co. (DPICO); the maximum pressure in the plunger chamber (P p) and total amount of fuel injected into a cylinder per cycle (Qf) at each operational condition. The result shows that the average error rate (%)of P p andQ f are 2.90% and 4.87%, respectively, in the specified operational conditions. Hence, it can be concluded that the analytical simulation algorithm developed in this study can be reasonably applied to the performance prediction of newly designed UI system.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

Abbreviations

A:

Cross-sectional area

C:

Discharge coefficient

D:

Effective diameter

d:

Diameter

f:

Friction factor

hp :

Plunger piston lift

Kf :

Bulk Modulus of fuel

L:

Length

mf :

Mass flow rate of fuel

N:

Rotational speed of plunger cam

n:

Number of hole

P:

Pressure

t:

Time

V:

Volume

Vo :

Injection velocity

β:

Compressibility factor of fuel

pf :

Density of fuel

δ:

Diameter ratio of nozzle inlet to outlet

ζ:

Effective diameter ratio

sp, in. out :

Spill line, inlet, outlet

N, pp:

Injection nozzle, plunger piston

S:

Solenoid valve

0:

Orifice

01, 02, 03, 04:

Model number

sv:

Solenoid valve seat

1, 2:

High-pressure line number

inj,bulk,leak,fric:

Injected, compressed, leaked, friction loss

cyl, p, s, fp :

Engine cylinder, plunger chamber, solenoid chamber, fuel pump

1, 2,m f, total:

High-pressure line 1, 2, injected fuel, total volume of injection system

References

  • ASME Fluid Meters Research Committee, 1981,the ISO-ASME Orifice Coefficient Equation, Mech. Engr., pp. 44–45.

  • Heywood, J. B., 1988,Internal Combustion Engine Fundamentals, McGraw-Hill Book Company, pp. 491–566.

  • Ichihashi, I., Takaishi, T., Tosa, T. and Yoshinori N.,Studies on Fundamental Characteristics Comparison of Unit Injector and PumpLine-Nozzle Injection Systems, Mitsubishi Heavy Industries, Ltd.,

  • Irving Granet, P. E., 1996,Fluid Mechanics, 4th Edition, Prentice Hall, pp. 320–329.

  • Kim, C. H., 1995, “Modelling of Mixed Gas Generation Processes in a Fuel Injection System of an S.I. Engine.” Ph. D. Thesis. The University of New South Wales

  • Kim, C. H., 2001, “Cycle Simulation for the Performance Prediction of a High Pressure Unit Injection System of a Diesel Engine,”KSAE Journal, Vol. 9, No. 1, pp. 63–74.

    Google Scholar 

  • Kouremenos, D. A., Hountalas, D. T. and Kour-emenos, A. D., 1999, “Development and Validation of a Detailed Fuel Injection System Simulation Model for Diesel Engines,”Intl. Congress and Exposition of SAE, 1999-01-0527, pp. 215–222.

  • Lee, J. K., et al, 1997, “Development of Electronic Unit Injector for Diesel Engines,”Technical Report, Korean Ministry of Commerce, Industry and Energy, pp. 54–103.

  • Pulkrabek, W. W., 1997,Engineering Fundamentals of the Internal Combustion Engine, Prentice Hall International Inc., pp. 165–205.

  • Rose, J. W. and Cooper, J. R, 1977,Technical Data on fuel, Proceedings of 7th The British National Committee World Energy Conference, pp. 147–291.

  • Table Curve 2D v5.0 Trial Fit Program, 2001. White, F. M., 1994,Fluid Mechanics, 3rd Edition, McGraw-Hil Book Company, pp. 314–326.

Download references

Author information

Authors and Affiliations

  1. A/Professor, Department of Automotive Engineering, Seoul National University of Technology, 139-743, Seoul, Korea

    Chul- Ho Kim

  2. Graduate Student, Department of Automotive Engineering, Seoul National University of Technology, 139-743, Seoul, Korea

    Jong- Soo Lee

Authors
  1. Chul- Ho Kim
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Jong- Soo Lee
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Chul- Ho Kim.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Kim, C.H., Lee, J.S. An analytical study on the performance analysis of a unit-injector system of a diesel engine. KSME International Journal 17, 146–156 (2003). https://doi.org/10.1007/BF02984296

Download citation

  • Received:

  • Revised:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF02984296

Key Words

Search

Navigation