Section Modulus calculation and optimization
SECTION MODULUS CALCULATION
1 INTRODUCTION
SECTION MODULUS is the ratio of total moment resisted by the section to the stress in the extreme fiber. It gives an idea of how much load a structure can withstand if section modulus increases the moment of resistance increases, and hence its load-bearing capacity increases.
S=I/Y (1)
S = section modulus, I = moment of inertia, y = distance between the neutral axis and end of the object.
2 PROCEDURE TO CALCULATE SECTION MODULUS
- For the hood design, select the INTERSECTION CURVE command and take the cure in the o-y direction.
- Edit the sketch and, using the PROJECT CURVE command, project the intersection curve onto the sketch plane.
- Using the QUICK TRIM CURVE command, delete the inner curves of the outer and inner hood panel.
- Connect the blank spaces between the outer and inner panels to form a closed curve.
- In the analysis tab, select the SECTION INERTIA ANALYSIS command. The max. and min. MOI of the section is displayed.
- In the sketch plane, select the two furthest points and draw the reference lines perpendicular to it. Using the RAPID DIMENSIONING command, find the dimension.
- Half of the dimension is the ‘y.’
- Calculate the section modulus using Eq. 1.
- For the new section, offset the inner panel curve to 0.5 mm and follow the same procedure.
4 CONCLUSION
From the challenge, the calculation of section modulus for the different sections is studied using NX CAD. Tools like SECTION INERTIA is exposed.