Page 10 - Combined_137_OCR

SPACE DIVISION CHRYSLER __
CORPORATION

Third, it is proposed that a survey of low speed wind tunnels be made to
develop candidate facilities. Cost is always a significant parameter in any program, so
all available tunnels will be investigated to insure that maximum benefits are derived from
dollars expended. Availability, particularly with government owned facilities, is often a
critical factor. This factor will be cleared early in the program. Tunnel operating
parameters (temperature, dynamic pressure, velocity, R^) will be obtained for each
facility. Test section size, physical and effective, will be ascertained. Also, tunnel
turbulence level and blockage ratio will be determined for each installation.

Much work has been done in developing solid and wake blockage correction
factors for low speed wind tunnels where wing and circular body combinations are being
tested (References 11, and 12). Formulas have been developed with parameters which
depend only on the shape being tested. Empirical values have then been formulated to
cover most any wing-body combination which might be found in airplanes. However, very
little data is available to know how to apply these correction factors when automobile shapes
are being investigated in the tunnel. Therefore, during this study, as well as while testing
at the tunnel (Phase HI), data will be generated which will allow proper correction factors
for solid and wake blockage to be applied to the wind tunnel data gathered on automobiles.

Utility of the tunnel will be of prime concern. It would be desirous that the
tunnel have conducted automobile tests in the past. The tunnel must be adaptable o a S
ground plane. For full scale testing, it would be desirous to have a dynamometer arrange­
ment in the test section. Sufficient instrumentation must be available to assure successful
test data. The data collection apparatus must be capable of providing the desired data
accuracy and yielding data in coefficient form, in a short period of time. All the above
information will be presented in tabular form in handbook fashion to aid in facility selection.

For increased data validity, it is desirable that experimental data be obtained
in more than one facility. For this reason several facilities may be selected in which tests
will be conducted. Additionally, to help resolve any scale effects, several different size
models may be investigated (i.e., full-scale, 3/8 scale). Before final selection of a facility
or facilities is made, personal inspection of the candidate tunnel(s) should be made and the
tests discussed with tunnel personnel to insure complete understanding on test items. CHO
proposes to perform these functions.

Throughout this first study phase, formulative ideas will be generated and
testing concepts visualized. Having established a close working arrangement with CEO
these ideas will be transformed into test criteria with guidance from stylists as to limits
and boundaries on configuration changes. By the conclusion of this phase, a firm foundation
for a testing schedule will have been made.

7