Section Modulus calculation and optimization
SECTION MODULUS:
Section modulus is the ratio of area moment of inertia about the neutral axis and to the distance of outermost fibre from the neutral axis.
Units: mm^3 or m^3
S = I / Y
Where,
S - Section modulus
I - Moment of inertia
Y - Distance from neutral axis to outremost fibre
AREA MOMENT OF INERTIA:
The area moment of inertia of a beam cross section area measured the beam ability to resist bending.
Where,
M - Bending movement
I - Area moment of inertia
E - Young modulus
σ - Bending stress
NEUTRAL AXIS:
Neutral axis is a layer in perticular cross section where there will be in either tension nor compression.
SECTION MODULUS:
CALCULATION:
CASE 1:
Here we are considered the inner panel section to section inertia analysis after doing we got the desired result shown in the above image
I(MAX) - 8.98150238e^07 [mm^4]
I(MIM) - 2.68949707e^05 [mm^4]
S = I / Y
I - I(MIM) Value is considered
Y - Total distance / 2
Y = 876.8053/2
= 438.402
S1 = 2.68949707e^05 / 438.402
S1 = 61.3477
CASE 2:
In order to increase the section modulus, cross sectional area has to be increased.
I(MAX) - 8.964856323e^07 [mm^4]
I(MIM) - 2.729225073e^05 [mm^4]
S = I / Y
I - I(MIM) Value is considered
Y - Total distance / 2
Y = 876.8053/2
= 438.402
S2 = 2.729225073e^05 / 438.402
S2 = 62.253
RESULT:
- After the calculation of the above cases the section modulus of S1 and S2 is differ.
- The section modulus value of CASE 2 is higher than the CASE 1. So-----S2 > S1
- As we increase the section area, the moment of inertia and section modulus increases which means strength and load material also increase which the moment of inertia is directly proportional to the strength of the material.