naca-report-429
- Version
- 173 Downloads
- 1.46 MB File Size
- 1 File Count
- August 26, 2016 Create Date
- August 26, 2016 Last Updated
National Advisory Committee for Aeronautics, Report - The NACA Apparatus for Studying the Formation and Combustion of Fuel Sprays and the Results from Preliminary Tests
This report describes the apparatus as designed and
constructed at the Langley Memorial Aeronautical Iab-
oratory, for studying the formation and combustion of
fuel sprays under conditions closely simulating those oc-
curring in a highnspeed compression-ignition engine.
The apparatus consists of a single-cylinder modified test
engine, a fuelinjection system so designed that a single
charge of fuel can be injected into the combustion chamber
of the engine, an electric driving motor, and a high-speed
photographic apparatus. The cylinder head of the engine
has a vertical-disk form of combustion chamber whose
sides are glass windows. When the fuel is injected into
the combustion chamber, motion pictures at the rate of
2,000 per second are taken of the spray formation by
means of spark discharges. When combustion takes
place the light of the combustion is recorded on the same
photographic film as the spray photographs.
The report includes the results of some tests to determine
the effect of air temperature, airflow, and nozzle design
on the spray formation. The results show that the com—
pression temperature has little effect on the penetration of
the fuel spray but does affect the dispersion, that air
velocities of about 800 feet per second are necessary to
destroy the core of the spray, and that the eject of air
flow on the spray is controlled to a certain erctent by the
design of the injection nozzle. The results on the com-
bustion of the spray show that when ignition does not
take place until after spray cut-01f the ignition may start
almost simultaneously throughout the combustion chamber
or at difl'erent points throughout the chamber. When
ignition takes place before spray cut—01f the combustion
starts around the edge of the spray and then spreads
throughout the chamber.
During the past five years the National Advisory
Committee for Aeronautics has published considerable
information on the formation of fuel sprays for high—
speed compression-ignition engines. The majority of
the investigations reported have dealt with the effects
on the fuel spray of the injection—nozzle design, of the
injection system, and of the density of the air into which
the fuel has been sprayed.
File | Action |
---|---|
naca-report-429 The NACA Apparatus for Studying the Formation and Combustion of Fuel Sprays and the Results from Preliminary Tests.pdf | Download |
Comment On This Post