Hood - Section Modulus calculation and optimization

SECTION MODULUS CALCULATION AND OPTIMIZATION OF HOOD

Section modulus is used to measure strength of the Cross - sectional area of an object about reference axis (neutral axis). If the material having higher strength, it has a higher capable of supporting greater loads.

Strength can be directly proportional to the Section modulus. So, we increase the cross-sectional area it can be increases the strength of the material.

Section modulus is represented by,

S=I/Y

Where I – moment of inertia

Y – Distance from the reference line (neutral axis) to extreme end of an object.

• The moment of inertiais defined as the product of mass of section and the square of the distance between the reference axis and the centroid of the section. Moment of inertia is nothing but offering resistance against of moment, bending or twisting. 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, having the higher resistance to deform under certain load, hence we can say that moment of inertia is directly proportional to the strength of the material.
• When the neutral axis is lies on the middle of the hood, then it is having the higher strength, if we change the position of the neutral axis, it will affect the strength of hood.

Let, gets calculated the strength of the hood panel,

UNMODIFIED HOOD:

When you see the pictures, it will show the unmodified hood moment inertia. Using the NX Cad platform,

MOI (max) = 9.154975 X 10^⁷mm4

MOI (min) = 2.739473 X 10^⁵mm4

Total length of the Hood (Y)= 885.0452mm

So, Half of the length is (^Y/₂) = 442.5226mm

1. Section modulus (max) => S_{max =} I_max/_Y

= 9.154975 X 10^⁷/442.522

= 206.881X10^³mm³(Maximum Strength)

2. Section Modulus (min) => S_min = I_min/_Y

= 2.739473 X 10^⁵/442.522

= 0.619X10^³ mm³ (Minimum Strength)

So, the Strength of the Hood varies between 0.619X10^³mm³ to 206.881X10^³mm³.

MODIFIED HOOD:

Offsetting the hood inner panel in 0.5mm and Creating the Emposses on the Hood inner panel.

MOI (max) = 9.205210 X 10^⁷mm4

MOI (min) = 2.842379 X 10^⁵mm4

Total length of the Hood (Y)= 885.0452mm

So, Half of the length is (^Y/₂) = 442.5226mm

1. Section modulus (max) => S_{max =} I_max/_Y

= 9.205210 X 10^⁷/442.522

= 208.017X10^³mm³(Maximum Strength)

2. Section Modulus (min) => S_min = I_min/_Y

= 2.842379 X 10^⁵/442.522

= 0.642X10^³mm³ (Minimum Strength)

When I increase the Cross Section area of the hood, it increases the moment of inertia as well as Strength.

So, the Strength of the Hood varies between 0.642X10^³mm³ to 208.017X10^³mm³.

CONCLUSION:

When you get from the results you will know that, strength of the material is directly proportional to the Moment of inertia. Hence, we increase the cross -section area of the hood, it will increase the mass of the object as well as increase the strength of object. So, it will offer resistance against force acting on the Hood panel.