Section Modulus calculation and optimization

TITLE :- Section Modulus calculation and optimization

OBJECTIVE :- Use the Section from your Hood design and calculate the section modulus and also Come up with a new section that has improved the section modulus of the previous section and mention what change you made that has increased the strength.

INTRODUCTION

MOMENT OF INERTIA:- The area moment of inertia is a property of a two-dimensional plane shape which characterizes its deflection under loading. It is also known as the second moment of area or second moment of inertia. The area moment of inertia has dimensions of length to the fourth power. Area moment of inertia is usually denoted by the letter I.

SECTION MODULUS :- The ratio of moment of inertia of a section about neutral axis and the distance of extreme fiber from neutral axis.

YEILD MOMENT :- It is defined as the moment at which the entire cross section has reached its yield stress.

OBSERVATION

CASE 1:- Sectional analysis of my hood design.

I (max)= 4.986558743 e6 mm⁴

Y= distance between the neutral axis and the extreme end of the object =446.8 mm

S= I/Y

By calculation

S= 11.160605e3 mm³

Consider Stainless steel AISI 302 – cold-rolled – y = 520 MPa

Yield moment = S * Yield strength(Y)

= 11.160605e3 * 520e6

= 5803.2e9 Nmm

CASE 2:- Improved section

For increasing the section modulus the distance between the outer panel and inner panel is increased by 4 mm.

I (max)= 5.10315520 e6 mm⁴

Y= distance between the neutral axis and the extreme end of the object =446.8 mm

S= I/Y

By calculation

S= 11.421564 e3 mm³

Consider Stainless steel AISI 302 – cold-rolled – y = 520 MPa

Yield moment = S * Yield strength(Y)

= 11.421564 e3 * 520e6

= 5939.2e9 Nmm

Hence the section modulus and yield moment increases by increasing the distance between the outer panel and inner panel.

CONCLUSION

As the section modulus is directly proportional to the moment of inertia so if moment of intertial increases then section modulus will also increases. We can change the moment of inertia by changing the distance between the outer panel and inner panel. Value of I can also be changed by changing the embosses. Yield moment will also increases due to increase in section modulus.