Section Modulus calculation and optimization

SECTION MODULUS:

Section Modulus is a geometric property used to calculate the Bending stresses in a structural member. Mathematically, It is defined as the ratio of the moment of inertia of a section about its centroidal axis and to the distance of the extreme layer from the neutral axis.

S = I/y

Where,

I = Moment of Inertia(m⁴)

y = distance from NA to extreme layer(m)

BENDING Stress:

When a beam is loaded with external loads all the sections will experience a bending moment. The bending moment at a section tends to bend or deflect the beam and the internal stresses resist its bending. The resistance, offered by the internal stresses to the bending, is called bending stress.

Calculation Of Section Modulus In HOOD:

Procedure:

• Take the intersection of curve wrt plane and the Hood Design
• fill the incomple sections with the help of curve commands
• measure the sectional interia using the section Interia analysis command in analysis section
• To Compare the our Hood Design with the another section i have created the another sketch with the lesser crossectional area so that the sectional interia might reduce
• after Creating the sketch the same Section Interia Command is used to analysis.
• and the Comaparision is made below.

CASE 1: SECTION MODULUS ANALYSIS OF THE HOOD DESIGN MADE BY MYSELF:

The Sectional moment of interia is below.

The Maximum Value = 8.25048 x 10^5`mm^4

The minimum Value = 5.44847 x 10^3 mm^4

Y = 473.7199/2 = 236.85995

S = (5.44847 x 10^3) / 236.85995 = 23.00 mm^3.

CASE 2: SECTION CREATED FOR COMPARISON:

The Maximum Value = 8.29675 x 10^5`mm^4

The minimum Value = 2.86807 x 10^3 mm^4

Y = 473.7199/2 = 236.85995

S = (2.86807 x 10^3) / 236.85995 = 12.10 mm^3.

Conclusion:

• From the Above Case study its clear that the Section Modulus and the moment of interia are directly proportional
• once we increase the crossectional area the moment of interia increses and vice versa so these two are directly proportional
• If the Section Modulus increses the strength of the section increses
• Thus its conclude that the Greater the thickness Greater the Strength.