Section Modulus calculation and optimization

    SECTION MODULUS OF AN HOOD

• Section modulus is a direct measure of strength of any  sectional area of an object about an reference axis(neutral axis).
• Strength is nothing but, capable of supporting greater loads, so higher the strength it has a high capable of supporting  greater loads.
• This strength can measured directly from Section modulus formula, and defined by below formula.
• Section modulus represented with a symbol of 'S'.

                                                                                        S=I/Y

      where 'I'moment of inertia

         'Y' is the distance from the reference line(neutral axis) to one of the extreme end of an object.

• Moment of inertia is nothing but offering resistance against of moment, bending or twisting, i.e if we applied any external load on the body, how much resistance its offering to tend to deform.
• So, higher the value of moment of inertia , have higher resistance to deform under certain load, hence we can say that moment of inertia directly proportional to the strength of the material , and strength of the material can be calculated with the help of section modulus.
• If we vary the  neutral axis towards positive or negative side the overall strength of the body will decrease , because when nuetral axis line lies on the middle of the section only have higher strength at particular point, so,  here 'Y'  value was inversely proportional to section modulus.

Thats why formula represented as above.

By using the same principle i going to calculate the strength of an hood panel.

Here the moment of inertia was calculated by using the NX-software obtained values are

I_MAX:-9.1701737X10⁷mm⁴

I_min:-2.6914323x10⁵mm⁴

Total length of 'Y' value was 879.86mm

So,at neutral axis we need 'Y' value:-c

1)Section modulus(S):-I/Y=9.1701737X10⁵mm⁴/439.412mm

                                         =3.471X10³mm³(Maximum strength).

2) Section modulus(S):-I/Y=3.18672x10³mm⁴/439.412mm

                                          =0.013x10³mm³(minimum strength).

So the strength of an hood varies from 0.013x10³mm³to 3.471X10³mm³

Now, one more trail is that, here the inner panel curve offsetting outside by 0.5mmi.e increasing in cross sectional area,the results shown below.

ined the values of

I_MAX:-8.4462X10⁵mm⁴

I_min:-3.61202x10³mm⁴

Total length of 'Y' value was 879.86mm

Y879.86

1)Section modulus(S):-I/Y=8.4462X10⁵mm⁴/439.412mm

                                                =1.922X10³mm³(Maximum strength).

2) Section modulus(S):-I/Y=3.61202x10³mm⁴/439.412mm

                                                =0.0822x10³mm³(minimum strength).

It shows the comparision the improve the strength of the hood design.