Section Modulus calculation and optimization

SECTION MODULUS CALCULATION AND OPTIMIZATION

OBJECTIVE:

To calculate the section modulus of the hood design using section inertia analysis from NX CAD.

MOMENT OF INERTIA:

Moment of Inertia is a quantity expressed by the body that resists the angular acceleration, which is the sum of the product of the mass of every particle with its square distance from the axis of rotation.

AREA MOMENT OF INERTIA:

It is nothing but the resistance of a cross-section towards bending.

SECTION MODULUS:

Section modulus is the ratio of the area moment of inertia about the neutral axis to the distance of the outermost fiber from the neutral axis.

Section Modulus:

S = I/Z

I = area moment of inertia

Z = Distance from the neutral axis to the outermost fiber.

S = Section Modulus.

SECTION INERTIA ANALYSIS:

SECTION 1:

The cross-section of the hood design has been considered for the frontal crash impact, and the section inertia analysis has been done using NX CAD.

Here, the minimum moment of inertia is taken into consideration, and the section modulus is calculated as follows:

I_min= 2.809239299e+05[mm⁴]

Z = 438mm (Half of the length of hood)

S = 641.378mm³

SECTION 2:

The cross-section of the hood design has been modified by increasing the depth of the hood's inner panel by 0.5mm for the frontal crash impact, and the section inertia analysis has been done using NX CAD.

Here, the minimum moment of inertia is taken into consideration, and the section modulus is calculated as follows:

Imin= 2.858088351e+05[mm4]

Z = 438mm (Half of the length of hood)

S = 652.531mm3

CONCLUSION:

Therefore, it is evident that the area moment of inertia improves when there is a change in the section of the hood design. The higher the section modulus, the higher the resistance towards bending.