2026-09-20T18:06:26Zhttps://api.drum.lib.umd.edu/server/oai/requestoai:drum.lib.umd.edu:1903/247172022-03-12T08:29:20Zcom_1903_2263com_1903_1654com_1903_2col_1903_2795col_1903_3
Shreeve, Charles A. Jr.
Billig, Frederick Stucky
Digital Repository at the University of Maryland
University of Maryland (College Park, Md)
Mechanical Engineering
2019-08-20T15:56:53Z
2019-08-20T15:56:53Z
1964
https://doi.org/10.13016/1t2k-ogk5
ILLiad # 1220057
http://hdl.handle.net/1903/24717
Supersonic combustion of reactive aluminum alkyl fuels has
been experimentally demonstrated in two-dimensional ducted combustors
and adjacent to a flat plate. Fuel was injected from the combustor
walls through multiple orifices and ignited spontaneously. Stable
supersonic heat release was maintained as evidenced by schlieren and
direct motion pictures of the flow field and deduced from static and
pitot pressure measurements in the combustion zone.
The results of the ducted combustor tests were correlated with
elementary one-dimensional and pseudo-one-dimensional theoretical models
of the flow field. This agreement permitted a reason.able determination
of combustion efficiency to be made. In the ducted combustor tests a
favorable effect of preheating the fuel to approximately 250°F was
noted and a simple empirical factor was found which satisfactorily
correlated all of the data for the range of conditions tested.
A theoretical model of constant pressure heat release on a flat
plate in supersonic flow is postulated. Normal force coefficients and
specific impulse values are tabulated for a variety of flight Mach
numbers and altitudes. Additional refinements in this theoretical
model were required to adequately describe the experimental results.
In a test simulating Mach 5 flight at 66,000 feet altitude a side force
specific impulse of 1350 seconds was measured at equivalence ratio of
one. Combustion was only partially completed 12 inches downstream of
fuel injection. Based on the theoretical mode l an additional 12 inches
of combustor length and 36 inches of expansion length would be required
to obtain the estimated theoretical impulse of 5760 sec.
The interaction of a vaporizing liquid droplet with a supersonic
stream is considered. Additional refinements were made in the
existing theories on droplet trajectory to include the influences of a
separated zone and the normal component of velocity of the external
stream. Calculations of the trajectory and evaporation of the estimated
mean droplet size based on the modified technique were in general agreement
with the observed flame zone and deduced combustion efficiency.
en
A Study of Combustion in Supersonic Streams
Thesis
open.access