Section Modulus calculation and optimization

SECTION MODULUS AND OPTIMIZATION

AIM:

The main objective of this challenge is to understand and learn the basic tools and advance tools used in NX cad and calculation as well as the section modulus and optimization for the car hood design.

SECTION MODULUS:

-Section modulus is a geometric property for a given cross-section used in the design of beams or flexural members. It is also referred to as the Polar Modulus or the Torsional Sectional Modulus.

-Other geometric properties used in design include area for tension and shear, radius of gyration for compression, and moment of inertia and polar moment of inertia for stiffness.

-Any relationship between these properties is highly dependent on the shape in question. Equations for the section moduli of common shapes are given below.

There are two types of section modulus:

1.The elastic section modulus and

2.The plastic section modulus.

FORMULA:

S=I/Y

Here,

S = Section modulus

I= Moment of Inertia (Unit mm 4)

Y= Distance from Neutral axis to the extreme end (unit mm)

The Unit of a “section modulus” is (mm3).

section modulus of various cross section are given below in thefollowing table,

SECTION MODULUS CALCULATIONS:

DISTANCE :

CASE:1

Section modulus is calculated by taking the intersection,

Moment of inertia (max) =5.925680320*10^4 mm^4

Moment of inertia (min) = 3.453731814 mm^4

Y = distance/2 =876.8460 / 2 = 438.423 mm

S(max) = I-max / y = 5.925680320*10^4 /438.423

S(max)=135.179*10^3 mm^3

S(min) = I-min / y = 3.453731814 /438.423

S(min)=0.0078*10^3 mm^3

In this case, the strength of the hood varies from 135.179*10^3 mm^3 to 0.0078*10^3 mm^3.

CASE:2

Section modulus is calculated by taking the intersection,

Moment of inertia (max) =8.937101890*10^4 mm^4

Moment of inertia (min) =4.482461916*10^3 mm^4

Y = distance/2 =876.8460 / 2 = 438.423 mm

S(max) = I-max / y = 8.937101890*10^4 /438.423

S(max)=203.846*10^3 mm^3

S(min) = I-min / y = 4.482461916*10^3 /438.423

S(min)=10.2240*10^3 mm^3

In this case, the strength of the hood varies from 203.846*10^3 mm^3 to 10.2240*10^3 mm^3.