Section Modulus calculation and optimization

Defination Section modules:

Section modulus is the ratio of bending to the farthest fiber from neutral axis, or it is the measure of the strength of the beam.

Ratio of Area Moment of Inertia to the Distance from the Neutral Axis to the Point where the Bending Normal Stress is determined.

Section modulus (S) = I/Y

I = Moment of inertia of structure.

Y = Distance between the neutral axis and the extreme end of the object.

Case 1 :

For my hood design the moment of inertia values are,

Maximum moment of inertia = 9.023298170e+07[mm^4]

Minimum moment of inertia = 2.772171586e+06[mm^4]

The total distance of the hood Y = 880.8mm

Distance between the neutral axis to the extreme end = (880.8/2) = 440.4mm

To find section modulus of HOOD section, we have to calculate

S= 2.7721/440.4

= 0.00629mm^3

Case 2:

In order to increase the resistance to bending of HOOD, I have make an improvement in section modulus of HOOD by giving 2 emboses seen clearly in below images.

Maximum moment of inertia = 9.405535558e+07[mm^4]

Minimum moment of inertia = 3.1097779094e+05[mm^4]

Y remains same

To find section modulus of new HOOD section, we have to calculate

S = 3.10977/440.4

= 0.00706mm^3

From the above calculations, I got an improvement in section modulus for about 0.000771 mm³

so that I also made an improvement in resistance to bending of my HOOD design.