Section Modulus calculation and optimization
AIM
To Use the Section from Hood design and calculate the Section Modulus using the formula
S = I/y
Where,
S = Section Modulus
I = Moment of Inertia
y = distance between the neutral axis and the extreme end of the object
PROCEDURE:
The data are collected from taking the master section using the mid plane
Front crash Original:
Front crash 1.5mm offset:
Side Crash Original:
Side Crash 1.5mm offset:
SECTION VIEW PIC
SAMPLE CALCULATION
CASE1)FRONT CRASH ORIGINAL
Imin (in Meters)=1.925*10^6 m
Imax(in Meters)=7.27*10^8 m
Imin (in mm)=1925000 mm
Imax (in mm)=727000000 mm
Total Dist=878.972mm
Y=Total Dist./2 = 439.486 mm
S=I/Y
Smin=Imin/Y ; Smax=Imax/Y
Smin=1925000/439.486 => 4380.11677 mm
Smax=727000000/439.486 => 1654205.14mm
Savg=(4380.11677+1654205.14)/2 => 829292.628mm
CASE2)FRONT CRASH 1.5MM
Imin (in Meters)=2.224*10^6
Imax(in Meters)=8.192*10^8
Imin (in mm)=2224000
Imax (in mm)=819200000
Total Dist=878.972
Y=Total Dist./2 = 439.486
S=I/Y
Smin=Imin/Y ; Smax=Imax/Y
Smin= 2224000/439.486=> 5060.45699
Smax=819200000/439.486 =>1863995.67
Savg=(5060.45699+1863995.67)/2 =>934528.063
By Comparing both the cases
829292.628mm < 934528.063mm
CASE1)SIDE CRASH ORIGINAL
Imin (in Meters)=1.666*10^6 m
Imax(in Meters)=1.41*10^8 m
Imin (in mm)=1666000 mm
Imax (in mm)=141000000 mm
Total Dist=484.983mm
Y=Total Dist./2 =242.4915 mm
S=I/Y
Smin=Imin/Y ; Smax=Imax/Y
Smin=1666000/242.4915 => 6870.34391 mm
Smax=141000000/242.4915 => 581463.68mm
Savg=( 6870.34391+581463.68)/2 => 294167.012mm
CASE2)SIDE CRASH 1.5MM
Imin (in Meters)=1.885*10^6
Imax(in Meters)=1.585*10^8
Imin (in mm)=1885000
Imax (in mm)=158500000
Total Dist=484.983
Y=Total Dist./2 = 242.4915
S=I/Y
Smin=Imin/Y ; Smax=Imax/Y
Smin=1885000/242.4915=> 7773.46835
Smax=158500000/242.4915 =>653631.158
Savg=(7773.46835+653631.158)/2 =>330702.313
By Comparing both the cases
294167.012mm < 330702.313mm
CONCLUSION
So, here the difference can be seen in the moment of inertia and the change in the section modulus can be seen by the change in the design.