A Comparison of Ignition Characteristics of Diesel Fuels as Determined in Engines and in a Constant-Volume Bomb Page: 2 of 11
This report is part of the collection entitled: National Advisory Committee for Aeronautics Collection and was provided to UNT Digital Library by the UNT Libraries Government Documents Department.
Extracted Text
The following text was automatically extracted from the image on this page using optical character recognition software:
' 3 1176 01425 7068
NATIONAL ADVISORY COMMITTEE FOR AERONAUTICS
TECHNICAL NOTE NO. 710
A COMPARISON OF IGNITION CHARACTERISTICS 0F DIESEL FUELS
AS DETERMINED IN ENGINES AND IN A CONSTANT-VOLUME BOMB
By Robert F. Selden
SUMMARY
Ignition-lag data have been obtained for seven fuels
injected into heated, compressed air under conditions
simulating those in a compression-ignition engine. The
results of the bomb tests have been compared with similar
engine data, and the differences between the two sets of
results are explained in terms of the response of each
fuel to variations in air density and temperature.
INTRODUCTION
Earlier tests with the N.A.G.A. high-temperature
bomb (reference 1) have shown that the ignition lag at
the highest bomb temperature is roughly twice that for
the same fuel in an N.A.O.A. high-speed Diesel engine hav-
ing a comparable air density at top center. The minimum
engine ignition lags reported by Schweitzer (reference 2)
are in substantial agreement with those obtained vith the
bomb.
It has been reported (reference 3) that the C.F.R.
engine fuel ratings are in substantially the same order
when either the critical-compression-ratio (0.C.R.) or
the ignition-delay method is used. The fact that the
0.C.R. method involves longer ignition lags than the de-
lay method indicates that the bomb would also give com- .
parable ratings provided that the greater air turbulence
in the engine was not an influential factor. On this
basis, tests were made in the bomb with fuels of differ-
ent ignition qualities, or different cetane numbers, to
determine the limitations of this apparatus for rating
Fuels. The test conditions included bomb temperatures of
8700 and 1,1550 F. and air densities of 0.59, 0.89, and
1.18 pounds per cubic foot.
Upcoming Pages
Here’s what’s next.
Search Inside
This report can be searched. Note: Results may vary based on the legibility of text within the document.
Tools / Downloads
Get a copy of this page or view the extracted text.
Citing and Sharing
Basic information for referencing this web page. We also provide extended guidance on usage rights, references, copying or embedding.
Reference the current page of this Report.
Selden, Robert F. A Comparison of Ignition Characteristics of Diesel Fuels as Determined in Engines and in a Constant-Volume Bomb, report, June 1939; (https://digital.library.unt.edu/ark:/67531/metadc54444/m1/2/: accessed April 18, 2024), University of North Texas Libraries, UNT Digital Library, https://digital.library.unt.edu; crediting UNT Libraries Government Documents Department.