ah ok well sounds fine as a solution, and i would like to know one more thing, if i want to make a study for layers with orientation angle then what type i must choose in the properties ? nonlinear elastic ?mep wrote:It is more the other way around; if the fibre orientation does not matter you can use isotropic properties. That is the assumption we are talking about. You have chopped strand mats which have a random orientation, but only in the x-y plane as sgth0mas pointed out. However, you pic the material properties which match a random orientated chopped strand mat. Those will be lower than what can be maximally achieved by UD but it will allow to build a much simpler simulation model because the material is assumed to be quasi isotropic. Obviously the final part will end up heavier but that’s the compromise taken for the simpler modelling and for safety.
ah i see, well this is a simulator cockpit where u sit it's just a simulator cockpit, now the second one i must do it a cockpit for an RC car which is 1/4 from the real one, let's say the real one is 1800mm in length, so mine should be 450mm in lengthsgth0mas wrote:Nonlinear elastic is technically correct, but it only benefits you if you load the material properties correctly to reflect the behavior over different strains. Clicking a button wont do too much wothout loading advanced properties. In FEA, especially non linear, you cant just use tensile strength, yield strength, modulus and density From one point. All of this data will be tabulated to detail the response at different strains, temperatures...etc.
If you are approximating this to be isotropic, i would also approximate non linear. The non linear is actually a less drastic approximation than isometric...especially if you have a lot of design margin.
This wont be taken to a race track correct?
here is a picture of how it looks like when i put non-linear elastic typesgth0mas wrote:Does your package allow for non-linear? Are you sure there arent other tabs?
Also, if you dont have the material properties, theres no sense in trying to solve a non linear.
What are the properties for the resin youre using (in psi please:))
i simply searched for the properties of E-Glass
well yesterday i was on the phone with one of my friends in his work he uses ansys for simulation, so he told me something about that curve, but what is it exactly, i mean is it just a relation between the stress and strain ? and where can i get it ? i tried some search on google but wasnt successful for e-glass fibersgth0mas wrote:as i use mostly ansys, im not sure why its not allowing more in solidworks. It may just be the package you have. Also, the tables and curves tab is where you would put the non-linear data related to the stress strain curves and such.
well this is what i found in my search from datasheets to other sources :Ssgth0mas wrote: Your tensile stregth is waaaaaayyyy too high...you cant use just fiber strength because its likely an order of magnitude greater than reality.
the problem is that we took some courses, about cercle de mohr and stress and strain, composite course, non-linear mechanics of structures, ... but we have some problems with that because we don't really know where to use thesesgth0mas wrote: Again, treat this as a linear isotropic but go with very conservative material properties if you cant find a close representation online or through testing. I dont think you have any other options. I mean almost resin only strength with a higher modulus. Thats your only choice as its the most conservative and you have actual values for that material. This is a good example of why FEA still requires someone well aware of what theyre doing with mechanics and materials.
And to throw in a disclaimer, this method would never be used in practice to design deliverable parts to a customer. I think youre simply going this route to satisfy academic requirements Correct?
thank you so much, i am in the Time zone UTC+2:00,sgth0mas wrote:Itll take me a bit to prepare a response for all that, but id be more than happy to help. What time country/timezone are you in...and when is your analysis due?
yesterday i was in a meeting with my tutor, i will have to make the composite analysis done totally next week max on tuesdaysgth0mas wrote:my last question was asking when you need to complete the solidworks analysis.
I will be tied up this weekend but can probably respond sunday evening or monday. Im in texas which i think is utc -6, im not sure if that changes with daylight savings time.
