Section Modulus calculation and optimization

REPORT

AIM

To calculate the section modulus for the previeously designed hood and optimized hood. To come up with the new section that has improved section modulus of the previous section.

What is Section Modulus?

Section modulus is a geometric property of a cross-sectional shape that describes its ability to resist bending. It is a measure of the shape's ability to distribute and resist external loads that create bending moments.

More specifically, the section modulus is the ratio of the moment of inertia of the cross-sectional shape about a neutral axis (the axis that experiences no bending stress) to the distance from the neutral axis to the outermost edge of the shape. This distance is known as the "extreme fiber distance" or the "maximum distance from the neutral axis."

The section modulus is a key factor in the design of beams and other structural members. By selecting a shape with a sufficient section modulus, engineers can ensure that the member will be able to resist bending forces without excessive deflection or failure. The section modulus is also used in calculations of the maximum allowable stress and the maximum bending moment that a member can withstand before it fails.

Section modulus is the measure of the strength of any section with respect to neutral axis.

The strength is measured by the section modulus formula.

S=I/Y

Were

S: section modulus

I: moment of inertia 

     resistance offered to any load creating moment , bending or twisting.

Y : distance from neutral axis to any extreme end

BEFORE OPTIMISATION

Moment of inertia(max) = 1.551543301×10^7×mm^4

Moment of inertia(min) = 1.116074936×10^5×mm^4

Y=487.3964/2=243.6982 mm

S=I/Y

S=1.116074936×10^5/243.6982= 457.974222214 mm^3

 

AFTER OPTIMISATION

Moment of inertia(max) = 1.550729421×10^7×mm^4

Moment of inertia(min) = 1.281947214×10^5×mm^4

Y=487.3964/2=243.6982 mm

S=I/Y

S=1.281947214×10^5/243.6982= 526.038852154 mm^3

CONCLUSION:

• By comparing the values we can say that section modulus of the optimized hood is increased.
• If we increase the gap between the inner and outer panel of hood eventually section length will increase thus MOI will increase.
• MOI increases with the increase of section length.
• MOI increases with the increase of section area.