Challenge

Section Modulus calculation and optimization

OBJECTIVE:

To Calculate the section modulus for the previously designed hood and optimized hood.
To Come up with the new section that has improved section modulus of the previous section.

MATERIAL OF THE HOOD:

SECTION MODULUS:

Section modulus is the geometric property of a given cross-section used in the design of flexural members. Section modulus depends only on the cross-section shape of the beam or structure.
For symmetric sections, the value of section modulus is the same for both above and below of centroid of the cross-section. An asymmetric section has two values for the top and bottom of the centroid, the maximum section modulus (Smax) and minimum section modulus (Smin).

There are two types of section modulus:

Significance of Section Modulus:

Section modulus is an important factor for designing beams and flexural members.
Higher the section modulus, higher will be the resistance to bending.
Easier to calculate strength and stresses in beams.
If two beams are made of the same material and the section modulus of two beams are being compared and vice versa, the beam with larger section modulus will be tougher and more capable to withstand larger loads.

We know that stress (σ) in a beam or structure is given by

σ=M⋅yIσ=M⋅yI...................(1)

Where I = Moment of Inertia

Y = distance between the neutral axis and the extreme end of the object

M = the moment about the neutral axis

Section Modulus is given by

S=IyS=Iy.......................(2)

From equations (1) and (2),

σ=MSσ=MS........................(3)

Thus from equation (3), it can be said that higher the section modulus, higher will be the resistance to bending.

# DESIGN 1: Section Modulus of Initial Hood Design

From the above analysis, following minimum and maximum moment of inertia are obtained

Imax = 9.105986649e+07 mm4

Imin = 3.019641841e+05 mm4

y = 438.5 mm

Smax = Imax / y = 9.105986649 / 438.5 = 0.0207662181277081 mm3

Smin = Imin / y = 3.019641841 / 438.5 = 0.0068862983831243 mm3

# CONCLUSION:

By comparing the values we can say that section modulus of the optimized hood (#Design 2) is increased by 1 %.
MOI increases with the increase of section area.
MOI increases with the increase of section length.
If we increase the gap between the inner and outer panel of hood eventually section length will increase thus MOI will increase.

Ship work like this
in your own course.