Section Modulus calculation and optimization

Section modulus of hood

Aim:-

To find the section modulus of hood and optimization to improve overall section modulus.

Section modulus is a geometric property for a given cross section used in the design of beam or flexural members.other geometric properties used in design include area for tension and shear,radius of gyration for compression,and second moment of rea and ploar second moment area for stiffness.Any relationship betwween these properties is highly dependent on the shapes.

There are two types section modulus:-

1.elastic modulus 

2.Plastic section modulus

S = I/y

 Where, 

S = Section Modulus

I = Moment of Inertia

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

Calculation:

Before Optimization

our Hood which was already created and the section inertia analysis is also done on it.

We have to make sure that the curve obtained is a single/closed curve.

                                                        Figure1.1

MOI (max) = 8.928754301e+07 (mm^4)

MOI (min) = 3.196609661e+05 (mm^4)

Total distance =875.5680mm

Y = 875.5680 / 2

   = 437.784 mm

Therefore, S = 319660.966 mm^4/437.784 mm

                    S = 730.179 mm^3

CASE 2: After optimization

The hood inner panel’s curve is offset by 0.5mm outwards and section inertia analysis is done same as case 1 for a closed curve.

MOI (max) = 8.910657812e^07 mm^4

MOI (min) = 3.264954768e^05 mm^4

As per section modulus equation,

Total distance =875.5680mm

Y = 875.5680 / 2

   = 437.784 mm

Therefore, S = 326495.4768 mm^4 / 437.784 mm

                   S = 745.792 mm^3

 

Conclusion:

Hence when comparing case 1 & case 2,

1. The section modulus value of case 2 is higher than the case 1

2. As we increase the section area, the moment of inertia & section modulus increases which means strength and load Material also increase