Research Papers: Internal Combustion Engines

New Methodology for the Identification of the Leakage Paths and Guidelines for the Design of Common Rail Injectors With Reduced Leakage

[+] Author and Article Information
A. Ferrari

Energy Department,
Politecnico di Torino,
Torino 10129, Italy
e-mail: alessandro.ferrari@polito.it

A. Mittica, P. Pizzo

Energy Department,
Politecnico di Torino,
Torino 10129, Italy

X. Wu, H. Zhou

Nanyue Fuel Injection Systems Co., Ltd.,
Hengyang 421007, China

1Corresponding author.

Contributed by the IC Engine Division of ASME for publication in the JOURNAL OF ENGINEERING FOR GAS TURBINES AND POWER. Manuscript received August 24, 2016; final manuscript received July 17, 2017; published online October 3, 2017. Assoc. Editor: Stani Bohac.

J. Eng. Gas Turbines Power 140(2), 022801 (Oct 03, 2017) (10 pages) Paper No: GTP-16-1421; doi: 10.1115/1.4037862 History: Received August 24, 2016; Revised July 17, 2017

The static leakage of a common rail (CR) injector is the flow-rate that is recirculated from the injector when the pilot-stage is not actuated. It is a critical issue in the development of modern CR injectors, because it can limit the maximum rail pressure level. An experimental methodology for splitting the static leakage between the contributions that pertain to the different leakage paths has been developed and applied to an innovative solenoid injector for the Brazilian, Russian, Indian, and Chinese (BRIC) market. The weak point of this injector was the excessively high static leakage compared to solenoid injectors for the European and U.S. markets. The static leakage splitting procedure allowed the sources of this leakage to be determined and a newly designed prototype was manufactured on the basis of the outcomes of this analysis. The new prototype featured a significant reduction (up to 54%) in the static leakage, compared to the original injector, and its leakage performance was almost the same as the typical one of Euro 5 solenoid injectors. Finally, a finite element method (FEM) analysis has been carried out on the improved BRIC injector. Guidelines are provided for a more refined design of some critical pieces of the component internal layout in order to further reduce its static leakage.

Copyright © 2018 by ASME
Your Session has timed out. Please sign back in to continue.


EUSME Centre, 2015, “ The Automotive Market in China,” Report Compiled in Partnership With the China-Britain Business Council, Beijing, China, Report No. 1.
SMI, 2013, “ China Diesel Engine Industry Report 2013–2016,” Sino Market Insight, Beijing, China Report No. MRS-699, p. 127.
Shen, X. , Yao, Z. , Zhang, Q. , Wagner, D. V. , Huo, H. , Zhang, Y. , Zheng, B. , and He, K. , 2015, “ Development of Database of Real-World Diesel Vehicle Emission Factors for China,” J. Environ. Sci., 31, pp. 209–220. [CrossRef]
Zhang, J. H. , and Chen, M. , 2015, “ Assessing the Impact of China's Vehicle Emission Standards on Diesel Engine Manufacturing,” J. Cleaner Prod., 107, pp. 177–184. [CrossRef]
Matsumoto, S. , Date, K. , Taguchi, T. , and Herrmann, O. E. , 2013, “ The New Denso Common Rail Diesel Solenoid Injector,” MTZ, 74(2), pp. 44–48.
Hermann, O. , Nagakawa, M. , Kenhard, M. , Schwab, H. , Miyaki, M. , Shinohara, Y. , Takeuchi, K. , and Uchiyama, K. , 2012, “ Ultra High Pressure and Enhanced Multiple Injection: Potentials for the Diesel Engine and Challenge for the Fuel Injection System,” Fuel Injection Systems for IC Engines, Woodhead Publishing, Cambridge, UK. [CrossRef]
Shinohara, Y. , Takeuchi, K. , Hermann, O. , and Laumen, H. J. , 2011, “ 3000 Bar Common Rail System,” MTZ, 72(1), pp. 4–8. [CrossRef]
Catania, A. E. , Ferrari, A. , Manno, M. , and Spessa, E. , 2008, “ Experimental Investigation of Dynamics Effects on Multiple-Injection Common Rail System Performance,” ASME J. Eng. Gas Turbines Power, 130(3), p. 032806. [CrossRef]
Batchelor, G. K. , 2000, An Introduction to Fluid Dynamics, Cambridge University Press, New York. [CrossRef]
Catania, A. E. , Ferrari, A. , and Spessa, E. , 2008, “ Temperature Variations in the Simulation of High-Pressure Injection-System Transient Flows Under Cavitation,” Int. J. Heat Mass Transfer, 51(7–8), pp. 2090–2107. [CrossRef]
Ferrari, A. , Paolicelli, F. , and Pizzo, P. , 2015, “ The New-Generation of Solenoid Injectors Equipped With Pressure-Balanced Pilot Valves for Energy Saving and Dynamic Response Improvement,” Appl. Energy, 151, pp. 367–376. [CrossRef]
Leonhard, R. , Warga, J. , Pauer, T. , Rückle, M. , and Schnell, M. , 2010, “ Solenoid Common-Rail Injector for 1800 Bar,” MTZ, 71(2), pp. 10–15. [CrossRef]
Zhang, Z. , and Hu, H. , 2013, “ Three-Point Method for Measuring the Geometric Error Components of Linear and Rotary Axes Based on Sequential Multilateration,” J. Mech. Sci. Technol., 27(9), pp. 2801–2811. [CrossRef]
Wang, J. D. , Guo, J. J. , Zhang, G. X. , Guo, B. A. , and Wang, H. J. , 2012, “ The Technical Method of Geometric Error Measurement for Multi-Axis NC Machine Tool by Laser Tracker,” Meas. Sci. Technol., 23(4), p. 045003. [CrossRef]
Hsu, Y. Y. , and Wang, S. S. , 2007, “ A New Compensation Method for Geometry Errors of Five-Axis Machine Tools,” Int. J. Mach. Tools Manuf., 47(2), pp. 352–360. [CrossRef]


Grahic Jump Location
Fig. 5

Static leakage splitting procedure: (a) prototype P1 for evaluation of Q7, (b) prototype P2 for evaluation of (Q6 + Q8), (c) prototype P3 for evaluation of Q5, (d) prototype P4 for evaluation of Q4, (e) prototype P5 for evaluation of Q3, and (f) prototype P6 for evaluation of Q2

Grahic Jump Location
Fig. 4

Internal layout of the innovative injector for the BRIC market

Grahic Jump Location
Fig. 3

Setup of the innovative injector for the BRIC market (circle symbol) and comparison with the ranges for typical Euro designs (dark zones). Rhomboid symbol refers to a Euro injector equipped with a pressure-balanced pilot valve.

Grahic Jump Location
Fig. 2

Static leakage as a function of pnom

Grahic Jump Location
Fig. 1

Experimental setup and KMM continuous flowmeter layout

Grahic Jump Location
Fig. 7

Torques acting on component B

Grahic Jump Location
Fig. 11

Analysis of design D2: (a) investigated layout (lower surfaces of A and B), (b) elastic displacements induced by Fax, and (c) elastic displacements induced by the fuel pressure

Grahic Jump Location
Fig. 12

Analysis of design D3: (a) investigated layout (lower and upper surface of A, lower surface of B), (b) elastic displacements induced by Fax, and (c) elastic displacements induced by the fuel pressure

Grahic Jump Location
Fig. 6

Protrusion of the injector pilot-stage feeding pipe

Grahic Jump Location
Fig. 8

Determination of the axial force due to the tightening torque

Grahic Jump Location
Fig. 9

Tightening and pressure forces acting on components A and B

Grahic Jump Location
Fig. 10

Analysis of design D1: (a) investigated layout (lower surfaces of A and B), (b) elastic displacements induced by Fax, and (c) elastic displacements induced by the fuel pressure

Grahic Jump Location
Fig. 13

Strained configurations due to Fax: (a) D1, (b) D2, and (c) D3



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