Hello everyone
I am using USDLFD subroutine in FORTRAN to model a component with 2 materials and smooth transition btwn both.
I based my work on the functionally graded structure and volume fraction. I used a sigmoid law in order to have a continous transition btw both materials.
I subdivided...
Ok and I make the link with material properties in the input file with dependencies right?
*Material, name=MAT
*Depvar
1,
*Elastic, dependencies=1
210000., 0.45, , 1.
1e+06, 0.45, , 10.
*User Defined Field
By a way it controls the interpolations in an element?
Thk you for your advice.
For the USDFLD program I came across a subroutine written by Emilio Martinez-Paneda for parameter transition between integration points. Here is the program:
SUBROUTINE USDFLD(FIELD,STATEV,PNEWDT,DIRECT,T,CELENT,
1...
Hello the community,
I want to make a simple example of FGM (functionally graded materials) finite element model but with continuous variation in elements. Not by modeling each layer with a different property buy by displaying the continuous transition between MAT A and MAT B in an element. See...
Hello,
I want to model the mechanical behavior of a printed component with multi material subjected to static load. The thing is I do not know how to model the materials data in my fe model.
I attached a picture of an example of multi material printed element.
I use ALTAIR HYPERMESH to...
Hello everyone,
I recently bought a 3D printer at home and I discover the joy to create parts with complex geometry for the day life. So I was wondering what could be the application in aircraft design. In fact this technology is 30 years old and if I don't say anything wrong there is just few...
Hello everyone,
I was wondering what is the effect of ribs position on a wing on the aerodynamic behavior and especially on the aeroelastic behavior. Does the position of ribs can change the dynamic behavior for a flutter phenomena for example.
I am not an expert in aircraft design so I do...
In order to have a positive input signal.
I agree with you, I first put 90 deg but my input signal was negative and I had to apply a -1 factor to my shock in order to have the same input than the one in ABAQUS. I then tried 270 deg and I have a positive signal without adding my -1 factor.
By...
Of course I agree it is important in this kind of analysis my point was about the origin of the difference between results.
Well in fact I am not sure it is the source of my problem here. I just run a sine sweep frequency on both codes and I obtained the same curve for the acceleration vs...
The analysis is based on the same FEM model (made in Hypermesh and exported in .inp for ABAQUS and .dat for NASTRAN) so I have the same number of nodes, elements, materials.
I made a previous modal analysis and I obtained the same frequencies, modes and effective masses with both codes.
Yes...
Hello everyone,
I made the same analysis in NASTRAN and ABAQUS in order to compare their performance and results.
It's a modal dynamic analysis (half sine shock), the shock is 0.011 s long and my analysis time is 0.22 s in order to see the behavior of the structure after the shock.
In...
Hey everybody
I want to make a modal dynamic analysis and I have to define the damping coeff of my structure. I am new to ABAQUS and I used to make analysis on NASTRAN.
Is the definition of this coeff is the same in both codes?
Thk in advance!
Hello everyone,
I want to calculate the response of a structure under a shock in NASTRAN.
I am using SOL 112 and the SPC/SPCD method: create SPC in my modal analysis input file (with restart lines), make a restart in my shock response file and using SPCD to apply my loading (TLOAD2).
The...
Hum I don't know if there is a way to find those docs on the internet or not...
They are well done and easier to understand than the manual.
Hope you'll find another way...i'll look after too
Dear all,
I have to compare ABAQUS and NASTRAN on sine sweep frequency analysis, I made my two input files (.inp for ABQ and .dat for NSTRN).
For NASTRAN I first made a modal analysis on a separate .dat input file and I defined my boundaries (SPC) in this file. I made a restart procedure in...
Dear all,
I want to perform a sine sweep analysis on an assembly and I wanted to be sure that the *STEADY STATE DYNAMIC was the good method for this. Can anyone tell me that's good?
I have another question, I want to make a restart from a modal anaylsis but every time wy analysis failed, it is...