Applications of auxiliary air injectors to supersonic wind tunnels Page: 4 of 55
This report is part of the collection entitled: National Advisory Committee for Aeronautics Collection and was provided to Digital Library by the UNT Libraries Government Documents Department.
The following text was automatically extracted from the image on this page using optical character recognition software:
NACA RM A53I01
the auxiliary air injector presents some attractive features on the
basis of the incompatibility between conventional air-compressor charac-
teristics and supersonic-wind-tunnel requirements. If the air that
must be bypassed to prevent compressor surge is channeled to an auxil-
iary injector, an improvement in both starting and running characteris-
tics of the wind tunnel would be expected.
In this report a one-dimensional analysis of the auxiliary-injector
principle is presented, together with some experimental results. Exam-
ples are given that demonstrate the improvement in operating character-
istics of both intermittent- and continuous-operation wind tunnels from
the standpoint of compression-ratio reduction.
& a sonic velocity, ft/sec
A cross-sectional area, sq ft
C any constant
cp specific heat at constant pressure, ft2/sec2Or
K stagnation pressure ratio, P-
injector mass flow
m mass-flow ratio, injector mass flow
test-section mass flow
M Mach number
P power, ft-lb/sec
p static pressure, b/sq ft abs
Q flow quantity, based on compressor intake conditions, cu ft/min
r compression ratio
rf correction factor,
R perfect-gas constant, ft2/sece/oF
Here’s what’s next.
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.
Spiegel, Joseph M.; Hofstetter, Robert U. & Kuehn, Donald M. Applications of auxiliary air injectors to supersonic wind tunnels, report, November 25, 1953; (https://digital.library.unt.edu/ark:/67531/metadc60515/m1/4/: accessed March 19, 2019), University of North Texas Libraries, Digital Library, https://digital.library.unt.edu; crediting UNT Libraries Government Documents Department.