Section Modulus calculation and optimization

                                                               SECTION MODULUS 

what is section modulus?. 

                       Section modulus is a geometric property for a given cross-section used in the design of flexural members.

and its defined as the ratio of area moment of inerti about the neutral axis and and the distance of outer most fiber from the neutral axis.

                                           Z = I/Y               [unit - mm3 or m3 ]

                  where,   Z = Section modulus.

                                I = Area moment of inertia.

                               y = Distance from neutral axis to the outer most fiber.

SECTION MODULUS FOR HOOD DESIGN

here we are analysing section modulus for front impact situaton.

                    so we need to create a section at the center of hood in perpendicular direction with the impact direction in order conduct section inertia analysis. 

                                 

after the intersection is made we we create a sketch and project the section in to the sketch and make it as closed curve.

after that we use the section inertia analysis for finding area moment of inertia.

we got area moment of inertia as

                                       max = 9.067 .mm4

                                       min = 2.69 .mm4

for the safety concern we always take the minimum value.

as we got the Aera MOI next we need the distance from the nautral axis to the outer most fiber( Y ).

we gat length of hood intersection from ita 2 extream points as 

                                                                                               = 879.9 which can take as = 880

 so for finding section modulus we know that

 Z = I/Y               [unit - mm3 or m3 ]

                  where,   Z = Section modulus.

                                I = Area moment of inertia.

                               y = Distance from neutral axis to the outer most fiber.

I = 2.69 .mm4

Y = 880/2 =440MM

    section moduldus Z = 2.69/440            

                                    = .00611                            

note:- when calculating Z i have doubt with in which unit i should take Y , here i take it in mm. and i will clear my doubt in live section tomorrow.

in order to improve the strength of the hoos we have meny ways such as increase the number of embosses, change the strecture of inner panle etc.

here we do  modify the curve section which pepict the we modified the design. so we offset the innerpanel intersection to 5mm outward which will increase the area moment of inertia.

since the section modulus is directly propotional to the area MOI, an increase in MOI can make improvement  in section modulus also.

after modified the 

                          I = 2.74

and y is constent = 440

               Z = 2.74/440

                  =0.0063

so we can see a slight improvement in section mosulus after we modifies the hood.