ee
seahrc
a
a speed test
‘ Sees SoNS
neon i lh ila
tl
spirometry
oe
eenensoned
mean averageof the values obtained at each station.
The values of the peak overpressure have been reduced to 1 KT
at sea level and plotted in Figure 4.1, elong with the reduced values
of succeeding shots and a standard 1.6-KT free-air curve.
oeno
Lnmeinmrngyn
e
Sante
i teasrseoannsdl
3.7 DYNAMIC PRESSURE MEASUREMENTS
During the present series of tests, a gage developed at Ballistic
Research Laboratories was. used to measure dynamic pressures. A
detailed description of the gage, its operation, and method of
-caltbration is presented in Appendix B. The definition of dynamic
j iA lessure in this case is the difference between the stagnation over: | Ruessure and the static or side-on pressure.
4
OS
No
;
Shot
- TABLE 3.7 - Dynamic Pressures
op
Station
Number | Humber
_
‘
3
6
Distance
from GZ (ft)
Ketual[A-Sealed
Static
Overpressure
: Total
Overpressure
Dynamic*
Preasure
Corrected
Dynamic Pressure
(pat)
(psi)
(pat)
(pat)
~rad.09
~, 6,500
333.02 i p> 205
1,280
1,616
7.48
43
8.60
5.20
1.12
0.77
1.10
0.76
4.15 f hie, 200
1,625
3.80
4.27
O47
0.47
9.20
8.50
LAP
r2ahibs
4
A photographic enlarge-
122.14
,800
1,734
15,396 NS
124,18
poe
124.21
124.23
€, «t A
7,600
;
697
352
564
_
3.75
20.0
0.50
29.2
122
319
32.5
23.5
197
0.50
135.0
56.0
37.6
23.5
14.2
20.3
12.8
124,24
7,900
22.4
34.5
124.25
8,501
19.0
27.8
8.8
8.2
124.26
8,992
16:8
23.7
6.9
6.5
*NOTE:
660]
3.25
oy
12.1
wa
The application of the pressure scaling factor produced no
significant changes in thege pressure values. Consequently the corrected
dynamic pressure values have been plotted against the appropriate reduced
distances in Figure 4.5,
ment of the initial portion of a wine
1 record is shown in Figure
5.8, The data from all shots on w
dynamic pressures were measured are listed in Table 3.7.
The vay s of dynamic pressures versus
distance from Shot 6 are plotted iayesof 3.7.
The peak dynemic
pressure values corrected for the compresBibility factor have been
reduced to i KT at sea level and plotted
theoretical. dynamic pressure curve based
Figure 4.5, along with a
a yield of 1.6 KT in free
air.
3.8
“3
oa
GROUND SURFACE ACCELERATION MEASUREMENTS
bony
g
During the past year research has been carried on by the
Explosion Kinetics Branch of the Ballistic Research
tories to
develop a simple accurate means of measuring ground a ee ration.
It was found feasible during UPSHOT-KNOTHOLE to use ti E ated class
disk of the BRL mechanical pressure-time gage for recording accclerations. With proper orientation the accelerameter elements will record
37