Accession Number:

ADA254532

Title:

Diesel Injector Fouling Bench Test Methodology

Descriptive Note:

Interim rept. Feb 1986-Jun 1992

Corporate Author:

SOUTHWEST RESEARCH INST SAN ANTONIO TX BELVOIR FUELS AND LUBRICANTS RESEARCH FACILITY

Report Date:

1992-06-01

Pagination or Media Count:

98.0

Abstract:

Compared to conventional compression ignition CI engine operation with the fuel being delivered at approximately 149 deg C 300 deg F, adiabatic engine operation potentially may deliver the fuel at temperatures as high as 260 deg C 500 deg F. Hypergolic CI engine combustion systems now in theoretical design stages will deliver fuel at temperatures approaching 427 deg to 538 deg C 800 deg to 1000 deg F. The ability of a fuel to resist formation of deposits on internal injector system surfaces is a form of thermal oxidative stability for which test methodology will be required. The injector Fouling Bench Test IFBT methodology evaluated in this report will assist in defining fuel contribution to injector fouling and control of fuel thermal stability in procurement specifications. The major observations from this project have included Forty-hour cyclic IFB tests employing both Bosch APE 113 and Detroit Diesel DD N70 injectors are viable procedures for evaluating fuel effects on injector fouling. Cyclic operation appears to be superior to steady-state operation for both type injectors. Eighty-hour cyclic tests are more discriminating am 40-hour cyclic tests using the Bosch APE 113 injectors. JFTOT tests of fuels provide directional information on thermal stability-related deposits and filter plugging but show limited good correlation with IFBT DD N70 ratings, and none with IFBT Bosch APE 113 injector ratings. Deposition on injector pintles was more realistically rated by optical microscopy and Scanning Electron Microscopy SEM than conventional visual and bench rating methods. High-sulfur fuel readily caused sticking of Detroit Diesel injectors. Injector sticking is an important mode of injector fouling.

Subject Categories:

  • Jet and Gas Turbine Engines

Distribution Statement:

APPROVED FOR PUBLIC RELEASE