21. Snap/Lurch 6 Angular—add four time intervals
The model and its justification
Snap/Lurch 6 is the angular equivalent of Snap/Lurch 6, which
added four time intervals to the simulation. It calculates the speed of the rearward lurch from the bullet, the cloud, and the large fragments,
with 3-D motions of the cloud, the large fragments, and the body: It begins by
interposing three steps having to do with the times. (1) It first calculates vsnap
and uses it to calculate tsnap. (2) Then it calculates ttransit
and combines it with tsnap with tdelay
to calculate tlurch. (3) Then it uses tlurch
and dfrags to calculate vfrags.
At this point it returns to the former procedure and (4) solves for vbodyafter
and vcloud. To simplify matters a bit, it sets vfrags23
= vfrag1 and fkefrags23 = fkefrag1.
These time intervals leave the default solution
about the same, however: -1.39 and 386 ft s-1 for lurch and cloud,
respectively, versus -1.38 and 378 ft s-1 in Lurch 5 Angular. The
sensitivities and effects also remain similar.
(1) Equations for tsnap

(2) Equations for tlurch
(3) Equations for vfrags
(4) Simultaneous equations for vbodyafter and vcloud
fkefrags23 = fkefrag1

Default values of variables
|
mbullet = 161 gr |
vbullet = 1800 ft s-1 |
mfrag1 = 0.027 gr |
|
mbody = 85 lb |
vbulletafter = 200 ft s-1 |
mfrags23 = 0.01 gr |
|
mcloud = 0.3 lb |
Qfrag1 = 40° |
fkefrag1 = 1.25 |
|
mhead = 7 lb |
Qfrags23 = 70° |
fkefrags23 = fkefrag1 |
|
Q = 12° |
Qcl = 70° |
fkebody = 1.2 |
|
PE = 300 ft-lb |
tdelay = 0.002 s |
fxcl = 0.59 (calc.) |
|
dtransit = 4 in |
dsnap = 2.2 in |
dfrag1 = 6 ft |
vbodyafter = -1.39 ft s-1 vcloud = 386 ft s-1
|
Angular momentum |
Energy, ft-lb |
||
|
Before |
After |
Before |
After |
|
Ωbullet = 3.80 |
Ωbulletafter = 0.43 |
KEbullet = 1164 |
KEbulletafter = 14 |
|
|
Ωbodyafter = -4.09 |
|
KEbodyafter = 1 |
|
|
Ωcloud = 6.42 |
|
KEcloud = 697 |
|
|
Ωfrag1 = 0.89 |
|
KEfrag1 = 111 |
|
|
Ωfrags23 = 0.15 |
|
KEfrags23 = 41 |
|
|
|
|
PE = 300 |
Sensitivity analysis
Sensitivity analysis, Lurch 6 angular
(Standard conditions in boldface)
|
mbullet |
vlurch |
mbody |
vlurch |
mcloud |
vlurch |
mhead |
vlurch |
vbullet |
vlurch |
|
|
|
|
|
|
|
4.0 |
-1.378 |
|
|
|
156 |
-1.353 |
|
|
|
|
4.5 |
-1.385 |
1750 |
-1.306 |
|
157 |
-1.362 |
65 |
-1.821 |
|
|
5.0 |
-1.392 |
1760 |
-1.325 |
|
158 |
-1.370 |
70 |
-1.691 |
|
|
5.5 |
-1.399 |
1770 |
-1.343 |
|
159 |
-1.378 |
75 |
-1.578 |
0.1 |
-0.468 |
6.0 |
-1.404 |
1780 |
-1.360 |
|
160 |
-1.385 |
80 |
-1.479 |
0.2 |
-0.990 |
6.5 |
-1.405 |
1790 |
-1.376 |
|
161 |
-1.392 |
85 |
-1.392 |
0.3 |
-1.392 |
7.0 |
-1.392 |
1800 |
-1.392 |
|
162 |
-1.398 |
90 |
-1.314 |
0.4 |
-1.731 |
7.5 |
-1.336 |
1810 |
-1.407 |
|
163 |
-1.403 |
95 |
-1.245 |
0.5 |
-2.030 |
8.0 |
-1.097 |
1820 |
-1.421 |
|
164 |
-1.409 |
100 |
-1.182 |
0.6 |
-2.300 |
8.5 |
— |
1830 |
-1.435 |
|
165 |
-1.414 |
105 |
-1.126 |
0.7 |
-2.550 |
9.0 |
— |
1840 |
-1.449 |
|
166 |
-1.419 |
|
|
0.8 |
-2.782 |
9.5 |
— |
1850 |
-1.463 |
|
|
|
|
|
|
|
10.0 |
— |
|
|
|
Sensitivity = |
Sensitivity = |
Sensitivity = |
Sensitivity = |
Sensitivity = |
|||||
|
Range = 0.07 |
Range = 0.70 |
Range = 2.31 |
Range = 0.28 |
Range = 0.16 |
|||||
|
vbulletafter |
vlurch |
PE |
vlurch |
Q |
vlurch |
Qcl |
vlurch |
mfrag1 |
vlurch |
|
|
|
0 |
-1.819 |
|
|
|
|
|
|
|
|
|
50 |
-1.753 |
7 |
-1.378 |
20 |
-2.744 |
0.022 |
-1.367 |
|
0 |
-1.280 |
100 |
-1.685 |
8 |
-1.380 |
30 |
-2.568 |
0.023 |
-1.372 |
|
50 |
-1.315 |
150 |
-1.615 |
9 |
-1.383 |
40 |
-2.333 |
0.024 |
-1.377 |
|
100 |
-1.347 |
200 |
-1.543 |
10 |
-1.385 |
50 |
-2.050 |
0.025 |
-1.382 |
|
150 |
-1.373 |
250 |
-1.468 |
11 |
-1.388 |
60 |
-1.731 |
0.026 |
-1.387 |
|
200 |
-1.392 |
300 |
-1.392 |
12 |
-1.392 |
70 |
-1.392 |
0.027 |
-1.392 |
|
250 |
-1.398 |
350 |
-1.312 |
13 |
-1.395 |
80 |
-1.045 |
0.028 |
-1.396 |
|
300 |
-1.383 |
400 |
-1.229 |
14 |
-1.398 |
90 |
-0.704 |
0.029 |
-1.401 |
|
350 |
-1.321 |
450 |
-1.143 |
15 |
-1.402 |
100 |
-0.383 |
0.030 |
-1.406 |
|
400 |
-1.124 |
500 |
-1.053 |
16 |
-1.405 |
110 |
-0.092 |
0.031 |
-1.411 |
|
|
|
550 |
-0.958 |
17 |
-1.408 |
120 |
+0.161 |
0.032 |
-1.415 |
|
|
|
600 |
-0.857 |
|
|
|
|
|
|
|
Sensitivity = |
Sensitivity = |
Sensitivity = |
Sensitivity = |
Sensitivity = |
|||||
|
Range = 0.16 |
Range = 0.96 |
Range = 0.03 |
Range = 2.90 |
Range = 0.05 |
|||||
|
mfrags23 |
vlurch |
Qfrag1 |
vlurch |
Qfrags23 |
vlurch |
fkefrags |
vlurch |
fkebody |
vlurch |
|
0.005 |
-1.398 |
|
|
|
|
1.00 |
-1.439 |
|
|
|
0.006 |
-1.397 |
20 |
-1.460 |
50 |
-1.435 |
1.05 |
-1.429 |
1.00 |
-1.392 |
|
0.007 |
-1.396 |
25 |
-1.447 |
55 |
-1.425 |
1.10 |
-1.420 |
1.05 |
-1.392 |
|
0.008 |
-1.394 |
30 |
-1.431 |
60 |
-1.415 |
1.15 |
-1.410 |
1.10 |
-1.392 |
|
0.009 |
-1.393 |
35 |
-1.413 |
65 |
-1.403 |
1.20 |
-1.401 |
1.15 |
-1.392 |
|
0.010 |
-1.392 |
40 |
-1.392 |
70 |
-1.392 |
1.25 |
-1.392 |
1.20 |
-1.392 |
|
0.011 |
-1.390 |
45 |
-1.368 |
75 |
-1.379 |
1.30 |
-1.382 |
1.25 |
-1.392 |
|
0.012 |
-1.389 |
50 |
-1.343 |
80 |
-1.367 |
1.35 |
-1.373 |
1.30 |
-1.391 |
|
0.013 |
-1.387 |
55 |
-1.316 |
85 |
-1.354 |
1.40 |
-1.363 |
1.35 |
-1.391 |
|
0.015 |
-1.386 |
60 |
-1.287 |
90 |
-1.342 |
1.45 |
-1.353 |
1.40 |
-1.391 |
|
0.015 |
-1.384 |
|
|
|
|
1.50 |
-1.344 |
|
|
|
Sensitivity = |
Sensitivity = |
Sensitivity
= |
Sensitivity = |
Sensitivity = |
|||||
|
Range = 0.01 |
Range = 0.17 |
Range = 0.09 |
Range = 0.10 |
Range = 0.00 |
|||||
|
fI |
vlurch |
dtransit |
vlurch |
dsnap |
vlurch |
dfrag1 |
vlurch |
tdelay |
vlurch |
|
1.06 |
-1.457 |
|
|
|
|
|
|
|
|