Section modulus optimization of a hood

Aim: To calculate the section modulus and modify the section to improve overall section modulus.

Introduction:

The section modulus is a geometric property which determines how much load a structure can withstand without failure.

Mathematically section modulus is defined as ratio of Moment of Inertia to the distance of extreme fiber from neutral axis.

S= I/y

where

S: Section modulus

I: Moment of Inertia

y: Distance between neutral axis and extreme end of object

Calculation of section modulus:

1.For existing section:

As we can see the minimum Moment of inertia in this case is 3796.9mm^4

In our case the neutral fiber y= 238.3 mm

Thus,

S=I/y= 3796.9/238.3= 15.933 mm^3

2.For modified Section:

In this case we have increased the inner panel offset to 0.8mm from the hood outer panel.

After increasing the hood inner offset away from outer panel by 0.8mm we can see the Inertia value increases compared to the initial existing case.

Here I=4083.5mm^4

and y remains same i.e 238.3

Thus,

S=I/y= 4083.5/238.3= 17.135 mm^3

Conclusion:

We can see that value of S increases as the distance between hood outer and inner panel increases as S is directly proportional to Moment of inertia. Thus the section is sucessfully optimised for better section modulus value.