...For a fillet weld, the required conditions are as follows:
1) equivalent stress < tensile ultimate strength / (beta_w * gama_M2)
2) normal stress prependicular to the weld throat < 0.9 * tensile ultimate strength / gama_M2
where,
beta_w : correlation factor function of the grade of the...
Hello,
In your case (linear static response of an elastic structure), the accuracy of the results obtained by a FE analysis depends mainly
of the data (boundary conditions, loading, material properties).
That means most of it you have listed as 'correct'.
If the data are 'correct', you can...
Hello,
The aim is to introduce kinematic constraints between dofs (contact, rigid body, hing joint, equality, ...).
U* = U + 1/2*p*phi^2 + k*lambda*phi
where,
k is a scale factor and phi is the kinematic constraint.
We consider 2 one-dimensional rods.
1 ____ 2 3 ____ 4
Node 4 is fixed...
Hello,
Your FEA code allows to connect shell to solid elements with the constraint relation called RSSCON.
Another basic solution is to write the kinematic constraints between the dofs of the facets of the solid elements on both sides of the shells and the rotational dofs of the shells. The...
Hello Greg,
The initial question of this post was to explain the practical usage of mode shapes.
That's why I propose the Modal Assurance Criteria which uses mode shapes to compare two models.
MAC is an possible and useful (in my experience too) usage of the mode shapes.
Regards,
Torpen.
Hello,
You can calculate the Modal Assurance Criteria (MAC) between two sets of modes. This can be used to compare the vibration modes of a condensed model (superelement)
with those of the original whole model.
Regards,
Torpen.
Hello,
you can find example solutions of Poisson's equation in 1-d and 2-d at the following link :
http://farside.ph.utexas.edu/teaching/329/lectures/node60.html
Regards,
Torpen
Hello,
We consider a fluid as a mixture of perfect gases.
The inputs are Z, Cp, Cv and gamma.
These parameters are defined as follows:
Cp = Cv+Z*R
gamma = Cp/Cv
Cp/R = gamma*Z/(gamma-1)
gamma = 1/(1-Z*R/Cp)
They vary at each point of the flow.
The equations of state are written as:
p/rho =...
...energy = translational energy + rotational energy
+ vibrational energy + electronical energy
Internal energy is equal to n*(0.5*R*T) where n is the number of dofs of the molecule.
For temperatures below 2000 K, there is 3 dofs in translation and 2 in rotation
and hence 5...
Hello,
The beginnings of your answer can be found in the following empirical formula :
k_wet = k_dry + w * k_wet
where,
w (kg/m3): water content
k_wet (W.m2/kg/K): proportional factor
Some values are given below :
k_wet w
expanded polystyrene...
Hello,
If you cannot set the initial temperatures of these bodies in Mechanica and then just allow the heat to flow (it seems to me very strange that it is not possible), you can apply (for example) a convective heat flux on the nylon with a very low heat transfer coefficient.
And perform your...
Hello,
A 3D structure has 6 rigid body modes whatever the finite element type. You can perform a free-free modal analysis and check the first eigenmodes to verify what cbrn said.
Regards,
Torpen
Hello,
The lumped capacitance method supposes negligible gradients at any instant during time (spatially uniform temperature). With the Fourier’s law this condition is impossible unless the thermal conductivity is infinite.
However this condition is approximately satisfied if the resistance to...
Hello,
A specimen in aluminum alloy (6000 series) is maintained at a temperature of the order 400 °C for a few seconds.
What are the values of the yield strength and of the Young's modulus at this temperature level.
I have basic data for static stress values until 350 °C (temperature applied...
Hello,
I hope this link will help you :
http://comp.uark.edu/~jjrencis/femur/Learning-Modules/The-Basic-Finite-Element-Equation/sdof2.html
Soft Spring
For such a spring the incremental force f required to produce additional incremental deformation u decreases as spring deformation increases...
...by cycle approach.
The whole stress field near to a crack tip can be characterised by a parameter K called stress intensity factor (SIF) :
K = Y * sigma * (PI * a)^1/2
The factor Y is the compliance-function. It is the change in stiffness as the crack grows.
For a central crack in an...
Hello,
Frederic Cugnon from the Liege University has written a doctoral thesis about the automatization of computation with p-version finite elements method.
In particular the chapter 2 compares h-version FEM versus p-version FEM.
It is written in french but the first pages of the chapter 2...
