CALCULATION AND OPTIMIZATION OF SECTION MODULUS OF A CAR HOOD
CALCULATION OF SECTION MODULUS OF HOOD
Objective:
To Create a section out of car hood and calculate the section modulus using Section Inertia Analysis command in NX CAD and optimize the section to improve the section modulus of the hood.
SECTION MODULUS:
It is used to calculate how much strength does a body of the component has and withstand impact force by considering a section of that component and analysing it. The section modulus is directy proportional to Moment of inertia and inversely proportional to the length neutral axis to the end of the component. It is denoted as 'S'
S = I/y
Where,
S = Section Modulus
I = Moment of Inertia
y = distance between the neutral axis and the extreme end of the object
CASE 1 (Considering the section having no offset):
So, By the above image, we get the values as shown:
I (max) = 5.61x10^6 mm^4
I (min) = 2.07x10^4 mm^4
The total length of the component is 932 mm, In order to get the value of Y,
Y = Total length / 2
Y = 932/2 = 466 mm
w.k.t. Section Modulus,
S = I/Y
NOW,
S (max) = I (max) / Y
S (max) = 5.61x10^6 / 466
S (max) = 12.03x10^3 mm^3
Similarly,
S (min) = I (min) / Y
S (min) = 44.4 mm^3
Hence the Section Modulus for both max and min are calculated.
S (max) = 12.03x10^3 mm^3
S (min) = 44.4 mm^3
CASE 2 (Offsetting the outer panel towards innner panel by 1.5 mm):
I (max) = 4.93x10^6 mm^4
I (min) = 1.82x10^4 mm^4
The total length of the component is 932 mm, In order to get the value of Y,
Y = Total length / 2
Y = 932/2 = 466 mm
w.k.t. Section Modulus,
S = I/Y
NOW,
S (max) = I (max) / Y
S (max) = 4.93x10^6 / 466
S (max) = 10.57x10^3 mm^3
Similarly,
S (min) = I (min) / Y
S (min) = 39.05 mm^3
Hence the Section Modulus for both max and min are calculated.
S (max) = 10.57x10^3 mm^3
S (min) = 39.05 mm^3
CONCLUSION:
Thus by varying the section of the component the Section modulus shows different results. It is simply proved that, Greater the section, greater will be the section modulus. Thus the section Inertia Analysis is analysed and calculated sucessfully.