0
Research Papers: Internal Combustion Engines

Understanding the Acoustic Oscillations Observed in the Injection Rate of a Common-Rail Direct Injection Diesel Injector

[+] Author and Article Information
Julien Manin

Sandia National Laboratories,
Combustion Research Facility,
7011 East Avenue,
Livermore, CA 94551
e-mail: jmanin@sandia.gov

Alan Kastengren

Argonne National Laboratory,
Center for Transportation Research,
9700 South Cass Avenue,
Building 362,
Argonne, IL 60439

Raul Payri

CMT–Motores Térmicos,
Universitat Politecnica de Valencia,
Camino de Vera s/n,
46022 Valencia, Spain

1Corresponding author.

Contributed by the IC Engine Division of ASME for publication in the JOURNAL OF ENGINEERING FOR GAS TURBINES AND POWER. Manuscript received July 9, 2012; final manuscript received July 13, 2012; published online October 11, 2012. Editor: Dilip R. Ballal.

This material is declared a work of the U.S. Government and is not subject to copyright protection in the United States. Approved for public release; distribution is unlimited.

J. Eng. Gas Turbines Power 134(12), 122801 (Oct 11, 2012) (10 pages) doi:10.1115/1.4007276 History: Received July 09, 2012; Revised July 13, 2012

Measuring the rate of injection of a common-rail injector is one of the first steps for diesel engine development. The injected quantity as a function of time is of prime interest for engine research and modeling activities, as it drives spray development and mixing, which, in current diesel engines, control combustion. On the other hand, the widely used long-tube method provides results that are neither straightforward nor fully understood. This study, performed on a 0.09-mm axially drilled single-hole nozzle, is part of the Engine Combustion Network (ECN) and aims at analyzing the acoustic oscillations observed in the rate of injection signal and measuring their impact on the real injection process and on the results recorded by the experimental devices. Several tests have been carried out for this study, including rate of injection and momentum, X-ray phase-contrast of the injector, and needle motion or injector displacement. The acoustic analysis revealed that these fluctuations found their origin in the sac of the injector and that they were the results of an interaction between the fluid in the chamber (generally gases) or in the nozzle sac and the liquid fuel to be injected. It has been observed that the relatively high oscillations recorded by the long-tube method were mainly caused by a displacement of the injector itself while injecting. In addition, the results showed that these acoustic features are also present in the spray, which means that the oscillations make it out of the injector, and that this temporal variation must be reflected in the actual rate of injection.

FIGURES IN THIS ARTICLE
<>
Copyright © 2012 by ASME
Your Session has timed out. Please sign back in to continue.

References

Musculus, M., 2009, “Entrainment Waves in Decelerating Transient Turbulent Jets,” J. Fluid Mech., 638, pp. 117–140. [CrossRef]
Payri, R., Garcia, J., Salvador, F., and Gimeno, J., 2005, “Using Spray Momentum Flux Measurements to Understand the Influence of Diesel Nozzle Geometry on Spray Characteristics,” Fuel, 84(5), pp. 551–561. [CrossRef]
Bosch, W., 1966, “Fuel Rate Indicator Is a New Measuring Instrument for Display of the Characteristics of Individual Injection,” SAE Paper No. 660749. [CrossRef]
Payri, R., Salvador, F., Gimeno, J., and Garcia, A., 2012, “Flow Regime Effects Over Non-Cavitating Diesel Injection Nozzles,” Proc. Inst. Mech. Eng., Part D (J. Automob. Eng.), 226(1), pp. 133–144. [CrossRef]
Payri, R., Climent, H., Salvador, F., and Favennec, A.-G., 2004, “Diesel Injection System Modelling. Methodology and Application for a First Generation Common Rail System,” Proc. Inst. Mech. Eng., Part D (J. Automob. Eng.), 218(1), pp. 81–91. [CrossRef]
Pickett, L., Genzale, C., Bruneaux, G., Malbec, L., Hermant, L., Christiansen, C., and Schramm, J., 2010, “Comparison of Diesel Spray Combustion in Different High-Temperature, High-Pressure Facilities,” SAE Int. J. Engines, 3(2), pp. 156–181. [CrossRef]
Kastengren, A., Manin, J., Pickett, L., Bazin, T., Powell, C., and Payri, R., 2012, “Engine Combustion Network (ECN): Measurements of Nozzle Diameter and Hydraulic Behavior of Diesel Sprays,” Atomization Sprays (submitted).
Potz, D., Chirst, W., and Dittus, B., 2000, “Diesel Nozzle: The Determining Interface Between Injection System and Combustion Chamber,” THIESEL 2000 Conference on Thermo and Fluid-Dynamic Processes in Diesel Engines, Valencia, Spain, September 13–15.
Lichtarowicz, A. K., Duggins, R. K., and Markland, E., 1965, “Discharge Coefficients for Incompressible Non-Cavitating Flow Through Long Orifices,” J. Mech. Eng. Sci., 7(2), pp. 210–219. [CrossRef]
Macian, V., Bermudez, V., Payri, R., and Gimeno, J., 2003, “New Technique for Determination of Internal Geometry of a Diesel Nozzle With the Use of Silicone Methodology,” Exp. Tech., 27(2), pp. 39–43. [CrossRef]
Payri, R., Salvador, F., Gimeno, J., and Bracho, G., 2008, “A New Methodology for Correcting the Signal Cumulative Phenomenon on Injection Rate Measurements,” Exp. Tech., 32(1), pp. 46–49. [CrossRef]
Kastengren, A., Tilocco, Z., and Powell, P., 2011, “Initial Evaluation of Engine Combustion Network Injectors With X-Ray Diagnostics,” ILASS-Americas 2011, Ventura, CA, May 15–18.
Kastengren, A., Powell, C., Wang, Y., Im, K., and Wang, J., 2009, “X-Ray Radiography Measurements of Diesel Spray Structure at Engine-Like Ambient Density,” Atomization Sprays, 19(11), pp. 1031–1044. [CrossRef]
Payri, R., Tormos, B., Salvador, F., and Plazas, A.-H., 2005, “Using One-Dimensional Modelling to Analyse the Influence of Diesel Nozzle Geometry in the Injection Rate Characteristics,” Int. J. Veh. Des., 39(1), pp. 58–78. [CrossRef]
Payri, R., Salvador, F., Gimeno, J., and Bracho, G., 2010, “The Effect of Temperature and Pressure on Thermodynamic Properties of Diesel and Biodiesel Fuels,” Fuel, 90, pp. 1172–1180. [CrossRef]
Payri, R., Salvador, F., Gimeno, J., and de la Morena, J., 2009, “Study of Cavitation Phenomena Based on a Technique for Visualizing Bubbles in a Liquid Pressurized Chamber,” Int. J. Heat Fluid Flow, 30, pp. 768–777. [CrossRef]
Crane, L., Birch, S., and McCormack, P., 1964, “The Effect of Mechanical Vibration on the Break-Up of a Cylindrical Water Jet in Air,” Br. J. Appl. Phys., 15, p. 743. [CrossRef]
Powell, C., Kastengren, A., Liu, Z., and Fezzaa, K., 2011, “The Effects of Diesel Injector Needle Motion on Spray Structure,” ASME J. Eng. Gas Turbines Power, 133, p. 012802. [CrossRef]

Figures

Grahic Jump Location
Fig. 1

Equivalent hole diameter along the orifice of the injector

Grahic Jump Location
Fig. 2

Mass flow and momentum flux as a function of time for the “Spray A” injection case

Grahic Jump Location
Fig. 3

Discharge coefficient as a function of Reynolds number for two discharge pressures

Grahic Jump Location
Fig. 4

Area coefficient as a function of Reynolds number for two discharge pressures

Grahic Jump Location
Fig. 5

Sketch of the experimental arrangement to record injector acceleration

Grahic Jump Location
Fig. 6

Phase-contrast imaging experimental arrangement to record needle motion

Grahic Jump Location
Fig. 7

Measured injection pressure (MPa), acceleration (m/s2 ), mass flow rate (g/s), and momentum flux (N) for two injection durations. The difference in time between control volume closure and EOI is also indicated. pinj = 150 MPa; pb = 20 bar.

Grahic Jump Location
Fig. 8

Normalized spectral density of ROI, momentum, acceleration, and line pressure at “Spray A”

Grahic Jump Location
Fig. 9

X-ray beam absorption to show injector oscillations during “Spray A” injection

Grahic Jump Location
Fig. 10

Needle position and speed in the axial direction as a function of time for the “Spray A” case

Grahic Jump Location
Fig. 11

Normalized spectral density of the acceleration, injector oscillations, and needle speed for “Spray A”

Grahic Jump Location
Fig. 12

Schematic of the injector showing the internal fuel tubing and the mechanism to action the needle

Grahic Jump Location
Fig. 13

Normalized spectral density of the ROI, momentum, and acceleration for the large oscillations period during a 4-ms-long injection

Grahic Jump Location
Fig. 14

Projected fuel density in the spray (0.1 mm from exit) as a function of time for “Spray A” injection. The dashed lines represent a period of the main oscillations.

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In