Section Modulus calculation and optimization
For Hood Design
Section modules:
Section modulus is the ratio of bending to the farthest fiber from neutral axis, or it is the measure of the strength of the beam.
Ratio of Area Moment of Inertia to the Distance from the Neutral Axis to the Point where the Bending Normal Stress is determined.
Section modulus (S) = I/Y
I = Moment of inertia of structure.
Y = Distance between the neutral axis and the extreme end of the object.
Case 1:
For my hood design the moment of inertia values are,
Maximum moment of inertia = 5.202601348e+06[mm^4]
Minimum moment of inertia = -67003.836191235[mm^4]
e total distance of the hood Y = 898.1738mm
Distance between the neutral axis to the extreme end = (898.1738/2) =449.0869 mm
To find section modulus of HOOD section, we have to calculate
S=-67003.836191235 /449.0869
= -149.2001mm^3
CASE 2: After optimization
Maximum moment of inertia = 5.202601348e+06[mm^4]
Minimum moment of inertia = 1.928783398e+04[mm^4]
e total distance of the hood Y = 898.1738mm
Distance between the neutral axis to the extreme end = (898.1738/2) =449.0869 mm
To find section modulus of HOOD section, we have to calculate
S=19287.83398 /449.0869
=42.949 mm^3
Conclusion:
Hence when comparing case 1 & case 2,
- The section modulus value of case 2 is higher than the case 1
- As we increase the section area, the moment of inertia & section modulus increases which means strength and load material also increase