Development of a Component Head Injury Criteria (HIC ... - FAA

1 2
3
4 6
5
Figure 31. Simulation Sequence for Impact Angle of 53 Degrees With ETHAFOAM Panel
for the NHCT
Table 9. Simulation Results of Panel Stiffness and Impact Angle for the NHCT
Stiffness (lb/in)
Impact Angle 50 100 150 200 300 400 500 600
HIC
31
(deg) HIC window
40 HIC
(deg) HIC window
53 HIC
(deg) HIC window
283
[Δt=15ms]
159
[Δt=15ms]
48
[Δt=15ms]
714
[Δt=15ms]
525
[Δt=15ms]
164
[Δt=15ms]
1040
[Δt=13ms]
850
[Δt=15ms]
347
[Δt=15ms]
1280
[Δt=11ms]
1152
[Δt=13ms]
536
[Δt=15ms]
1771
[Δt=15ms]
1589
[Δt=10ms]
884
[Δt=15ms]
2181
[Δt=8ms]
2020
[Δt=15ms]
1191
[Δt=13ms]
2774
[Δt=6ms]
2390
[Δt=7.0ms]
1488
[Δt=11ms]
3154
[Δt=6ms]
2733
[Δt=7.0ms]
1776
[Δt=10ms]
From the results of the parametric studies listed in tables 8 and 9, the HIC is inversely
proportional to the impact angle. This correlation is depicted in the following section.
6.4 CORRELATION OF MADYMO MODELS FOR FSST AND NHCT.
Correlation for impact angles of 31, 40, and 53 degrees was performed for the NHCT and FSST
MADYMO models.
6.4.1 Panel Stiffness and HIC at an Impact Angle of 31 Degrees.
Figure 32 shows the relationship between the panel stiffness and HIC value for the NHCT and
the FSST at an impact angle of 31 degrees. The HIC values for the NHCT and the FSST were
calculated using the coefficients derived in MADYMO (equations 1 and 2).
where: K = Stiffness of the panel (lb/in.)
HIC NHCT = 5.54 K (1)
HIC FSST = 5.22 K (2)
22