Section Modulus calculation and optimization

Section Modulus of HOOD DESIGN

section modulus theory is used to find the maximum strength of the job through its cross-sectional area with respect to the neutral axis of the job's cross-section.

Section modulus formula came from the Bending equation M/I = Sigma/Y = E/R and Section Modulus is S = I/Y.

where S = section Modulus, I = Moment of inertia of Body and Y = from Neutral axis to the one extreme end of object distance.

So for achieving the maximum Section Modulus, It is necessary that the Moment of Inertia (I) should be high and the neutral axis distance (Y) should be less. Where a moment of Inertia shows how to resist the bending and twisting moment and Neutral axis distance shows that which layer of material of the job is not under any stress before loading and after loading force on the job.

The moment of Inertia (I) is directly proportional to the Section modulus, It means if MOI (I) is high Section Modulus is high otherwise low. Similarly, the Neutral axis (Y) distance is inversely proportional Sectional modulus, It means if the neutral axis distance is low then the Section modulus is high otherwise low Section modulus value.

Section- Modulus of Hood cross sectional Area:

I extracted the property of Hood section by section Inertia analysis to calculate the Section Modulus and use it to make a higher resistance of shock and strain Hood during the accident.

From the above diagram, I got the minimum Moment of Inertia (I min) and Neutral axis (Y). Now from S= I(min)/Y, I will calculate the Section modulus for minimum strength.

S (min) = 22558.33/466.8085 (mm^4/mm)

S (min)= 48.324 mm^3 (we have to consider for designing)

For maximum strength Section modulus is

S (max) = 5.763436069 x 10^6/466.8085 (mm^4/mm)

S (max) = 12346.467 mm^3

The strength of Hood varies from 48.324 to 12346.467 mm^3

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New Section Modulus of Improve Hood Section:

I have increased the height of embossing where the Hinges are mounted and increased the 2 mm height of the centre rib so that MOI can be increased.

For designing purposes Minimum section modulus with minimum Moment of Inertia (MOI)

S (min) = 2.451871407 x 10^4 / 466.8148 (mm^4/mm)

S (min) = 52.568 (mm^3) (For Designing purpose)

S (max) = 5.8467065 x 10^6/466.8148 (mm^4/mm)

S (max) = 12524.68 (mm^3)

The strength of Hood varies from 52.568 to 12524.68 mm^3

Conclusion: Now the new modified Hood section is stronger than my old Hood section. Which can verify my vehicle safety criteria.