Section Modulus calculation and optimization

Section Modulus calculation and optimization

Section modulus :- Section modulus is a geometric property for a given cross-section used in the design of beams or any component with flexural properties. Other geometric properties used in the design include an area for tension and shear, the radius of gyration for compression, and moment of inertia and polar moment of inertia for stiffness.

Types of section modulus

• elastic section modulus
• plastic section modulus

Formulas for calculating section modulus are

For Elastic Section modulus

S = I/y

S - Elastic modulus

I - Area moment of inertia

Y - Distance between the center axis and the endpoint of the component.

2. For Plastic Section modulus

Zp = AcYc + AtYt

Z – Plastic modulus.

Ac or At – Areas of cross-sections.

Yc or Yt – Distance from the local centroids of the two areas.

For calculating Section modulus for my hood design, I will be using the Elastic section modulus formulae because it is the general formula for all section modulus calculations.

section from the hood

Calculating Section Modulus of the sketch by using ' Section Inertia Modulus' command

considering the minimum moment of inertia (MOI)

MOI(min):-1.438493745x 10⁴mm⁴

Y = 878.6mm/2

=439.3mm

From the above values, we can calculate section modulus of hood

S= I/Y

=1.438493745x 10⁴mm⁴ /439.3mm

=32.77mm^3

Modified sketch

Section is modified to improve the section modulus which interms refers to the improved strength

considering the minimum moment of inertia (MOI)

MOI(min):-1.503695065x 10⁴mm⁴

Y = 878.6mm/2

=439.3mm

From the above values, we can calculate section modulus of hood

S= I/Y

=1.503695065x 10⁴mm⁴ /439.3mm

=34.22mm^3

To improve the section modulus, the hood outer panel is offset by 1mm and the embosses on the inner of the inner panel is redeuced by 1mm.

CONCLUSION:- By modifing the section of hood, the section modulus of the hood is increased by 5%. which refers to the increase in strength.