Section Modulus calculation and optimization
The section modulus (S) is geometric property of the cross section used for designing beams and flexural members. It does not represent anything physically.
Formula of Section Modulus: It may be defined as the ratio of total moment resisted by the section to the stress in the extreme fiber which is equal to yield stress.
There fore
S = I/Y, Where
S = Section modulus (mm^3)
I = Moment of Inertia of the section about the bending axis. (mm^4)
Y = Distance between the neutral axis and extreme end of the object (mm)
- It gives an idea about how much of load the given structure can stand.
- If the section modulus increases strength or load bearing capacity of the part also increases.
Calculation:
CASE 1: Before Optimization
The Hood which was already created is imported and the section inertia analysis is done.
We have to make sure that the curve obtained is a single/closed curve.
MOI (max) = 4.732250 70e+03 (mm^4)
MOI (min) = 4.846200443+05 (mm^4)
As per the section modulus equation,
S = I/Y
I = MOI (min) value is considered
Y = Total distance /2, Total distance =487.6942mm
Y = 487.6942/ 2
= 243.84mm
Therefore, S = 4846.200443mm^4/243.84 mm
S = 198.74mm^3
Calculation:
CASE 2: After Optimization
The hood inner panel’s curve is offset by 0.5mm outwards and section inertia analysis is done same as case 1 for a closed curve.
MOI (max) = 4.720518025e+03 (mm^4)
MOI (min) = 5.163546247 (mm^4)
As per the section modulus equation,
S = I/Y
I = MOI (min) value is considered
Y = Total distance /2, Total distance =487.6942mm
Y = 487.6942/ 2
= 243.84mm
Therefore, S =5.163546247mm ^4/243.84 mm
S = 211.75mm^3
