Re: [Yade-users] [Question #699997]: Two phase flow engine
Question #67 on Yade changed: https://answers.launchpad.net/yade/+question/67 Description changed to: Hi every body I have to get the SWRC curve base on the experimental test (Pressure Plate ). It is vital to define surface tension which is physically equal to 0.0728 (N/m) for water, however I have seen in one of the examples (drainage-2PFV-Yuan_and_Chareyre_2017) that surface tension is equal to 10 (line 127). I've changed the number of surface tension, for example it was multiplied to 4 (0.0728*4) and then result became better since, the type of soil is fine-grained.Therefore I came up with these questions : 1) Why in above-mentioned example surface tension is equal to 10? Is it unit-less? 2) why when surface tension increased (0.0728*4 )sample drained slower? It means water content decreased slowly while, when surface tension is equal to 0.0728 water content drop sharply! -- You received this question notification because your team yade-users is an answer contact for Yade. ___ Mailing list: https://launchpad.net/~yade-users Post to : yade-users@lists.launchpad.net Unsubscribe : https://launchpad.net/~yade-users More help : https://help.launchpad.net/ListHelp
Re: [Yade-users] [Question #699932]: Modéliser un fluide hydraulique
Question #699932 on Yade changed: https://answers.launchpad.net/yade/+question/699932 Status: Answered => Open HANS MPOYO BWISHITA is still having a problem: Hello. I read you with great interest and above all [1]. since you said that it is possible to model hydraulic oil as in the case of a pump and a turbine. could you give me show me the modeling process and also how the script will be in the case of a pump (you can randomly choose an example representing a pump; and a turbine). the idea I have is to see how you managed to do the modeling and how the script will be presented. and thanks to this approach I will be able to adapt to my problematic, because it is quite complex. be sure if he understands you correctly this time and give me a favorable response. Le mar. 21 déc. 2021 à 13:25, Jan Stránský < question699...@answers.launchpad.net> a écrit : > Your question #699932 on Yade changed: > https://answers.launchpad.net/yade/+question/699932 > > Status: Open => Answered > > Jan Stránský proposed the following answer: > > Since you said that it is possible to model a hyrdaulic fluid in YADE; > > Definitely. > In an extreme case, it is possible to model a hydraulic fluid in pure > Python, so it is also possible in Yade. > Information of no value, but as described above, on the same quality level > as your question. > > To get an answer with value greater than zero, please provide (mch) > more information, e.g.: > - something about yourself, your background ... > - if/what you have tried already > - the scope of the task: > - university/industry > - one month short project/PhD topic ...) > - etc. etc. > > To improve the question, please describe what exactly means (got from the > OP): > - in YADE: why Yade? Why not dedicated software to "hydraulic fluid"? What > you expect from Yade compared to alternatives? > - a way: using existing features? implementing a new features? ... ? > - to model: any idea of a numerical method to be used? or just using it as > a black box? what scales, times, volumes...? What should be the output? ... > ? > - a hydraulic fluid: compressible/incompressible? what properties? under > what conditions? ... ? > - a hydraulic pump: any link, image, ... ? > - a hydraulic turbine: any link, image, ... ? > > > Please give me some possible solutions to my problem. > > Please, as you were asked many times already, first you describe > properly (i.e. with much more details) what your problem actually is. > Otherwise see below the proposed solution to your problem. > > > how can I do that > > Without more information, the best answer we can give is: > You choose a suitable numerical method(s) for your problem(s), implement > to Yade non-existent features if needed, and write a script doing what you > need. > > Cheers > Jan > > PS: as usually, please read [1] ... > > -- > If this answers your question, please go to the following page to let us > know that it is solved: > https://answers.launchpad.net/yade/+question/699932/+confirm?answer_id=4 > > If you still need help, you can reply to this email or go to the > following page to enter your feedback: > https://answers.launchpad.net/yade/+question/699932 > > You received this question notification because you asked the question. > -- You received this question notification because your team yade-users is an answer contact for Yade. ___ Mailing list: https://launchpad.net/~yade-users Post to : yade-users@lists.launchpad.net Unsubscribe : https://launchpad.net/~yade-users More help : https://help.launchpad.net/ListHelp
Re: [Yade-users] [Question #699998]: How to simulate small-strain triaxial compression test
Question #68 on Yade changed: https://answers.launchpad.net/yade/+question/68 Leonard posted a new comment: Hi, I came up with a way: using a small enough dt for the simulation. Do you have any other ideas? Cheers Leonard -- You received this question notification because your team yade-users is an answer contact for Yade. ___ Mailing list: https://launchpad.net/~yade-users Post to : yade-users@lists.launchpad.net Unsubscribe : https://launchpad.net/~yade-users More help : https://help.launchpad.net/ListHelp
Re: [Yade-users] [Question #699917]: "noFlowscenario.py" example not working
Question #699917 on Yade changed: https://answers.launchpad.net/yade/+question/699917 Status: Open => Answered Robert Caulk proposed the following answer: Thanks for the update, and thankyou for testing 18.04. I guess we have a bug in 20.04. I will work during New Year to fix that, and presumably 22.04. Happy holidays! Le ven. 24 déc. 2021 à 23:46, Zoheir Khademian < question699...@answers.launchpad.net> a écrit : > Question #699917 on Yade changed: > https://answers.launchpad.net/yade/+question/699917 > > Status: Needs information => Open > > Zoheir Khademian gave more information on the question: > Hi Robert and happy Christmas! > > >When do solid and fluid temps go to nan? > From the very beginning. I reduced the timestep but it was not the cause. > > >You should be testing yadedaily instead. I tested yadedaily too but got > the same results. > > >Is it possible for you to try with Ubuntu 18.04? > I finally got a chance to try noFlowScenario.py on Ubuntu 18.04 and was > able to successfully run it. > > I wish you a happy new year > > Zoheir > > -- > You received this question notification because your team yade-users is > an answer contact for Yade. > > ___ > Mailing list: https://launchpad.net/~yade-users > Post to : yade-users@lists.launchpad.net > Unsubscribe : https://launchpad.net/~yade-users > More help : https://help.launchpad.net/ListHelp > -- You received this question notification because your team yade-users is an answer contact for Yade. ___ Mailing list: https://launchpad.net/~yade-users Post to : yade-users@lists.launchpad.net Unsubscribe : https://launchpad.net/~yade-users More help : https://help.launchpad.net/ListHelp
[Yade-users] [Question #699998]: How to simulate small-strain triaxial compression test
New question #68 on Yade:
https://answers.launchpad.net/yade/+question/68
Hi,
I'd like to ask that how to simulate a drained triaxial compression test within
a small-strain level.
The goal of this simulation is to get the small strain stiffness G0.
A typical way is (1) generating a sand packing and isotropically load it to
target confining pressure, e.g., 100 kPa. (2) a small axial strain increment
deps1 is applied on the top wall, while the lateral stresses sigma2 and sigma3
keep constant. (3) the simulation finishes when the shear strain, gamma =
deps1-deps2, reaches 10e-6. (4) then G0 can be calculated by G0 =
dsigma1/(2*gamma)
What I have done is using the example code provided by Bruno[1]. I set the
loading rate to a very small value (1e-20), and the simulations finished in one
second. I thought this process is too quick to generate accurate results,
actually the lateral confining pressure changes (i.e., not constant). I know
this script works well for a classic triaxial compression test because usually
we look at a large strain level (like 20% of axial strain), thereby a small
amout of fluctuation on lateral stress is acceptable. But when we look at such
a small range and in such a short time, this will lead to inaccurate results.
So my question is how can we make the simulation of triaxial compression test
within a small-strain level.
Thanks,
Leonard
[1]https://gitlab.com/yade-dev/trunk/blob/master/examples/triax-tutorial/script-session1.py
The MWE is as follow if the question is not clearly described.
from yade import pack
nRead=readParamsFromTable(
num_spheres=1000,# number of spheres
compFricDegree = 30, # contact friction during the confining phase
key='_triax_base_', # put you simulation's name here
unknownOk=True
)
from yade.params import table
num_spheres=table.num_spheres# number of spheres
key=table.key
targetPorosity = 0.43 #the porosity we want for the packing
compFricDegree = table.compFricDegree # initial contact friction during the
confining phase (will be decreased during the REFD compaction process)
finalFricDegree = 30 # contact friction during the deviatoric loading
rate=-1e-20 # loading rate (strain rate)
damp=0.2 # damping coefficient
stabilityThreshold=0.01 # we test unbalancedForce against this value in
different loops (see below)
young=5e6 # contact stiffness
mn,mx=Vector3(0,0,0),Vector3(1,1,1) # corners of the initial packing
O.materials.append(FrictMat(young=young,poisson=0.5,frictionAngle=radians(compFricDegree),density=2600,label='spheres'))
O.materials.append(FrictMat(young=young,poisson=0.5,frictionAngle=0,density=0,label='walls'))
walls=aabbWalls([mn,mx],thickness=0,material='walls')
wallIds=O.bodies.append(walls)
sp=pack.SpherePack()
sp.makeCloud(mn,mx,-1,0.,num_spheres,False, 0.95,seed=1) #"seed" make the
"random" generation always the same
O.bodies.append([sphere(center,rad,material='spheres') for center,rad in sp])
triax=TriaxialStressController(
maxMultiplier=1.+2e4/young, # spheres growing factor (fast growth)
finalMaxMultiplier=1.+2e3/young, # spheres growing factor (slow growth)
thickness = 0,
stressMask = 7,
internalCompaction=True, # If true the confining pressure is generated
by growing particles
)
newton=NewtonIntegrator(damping=damp)
O.engines=[
ForceResetter(),
InsertionSortCollider([Bo1_Sphere_Aabb(),Bo1_Box_Aabb()]),
InteractionLoop(
[Ig2_Sphere_Sphere_ScGeom(),Ig2_Box_Sphere_ScGeom()],
[Ip2_FrictMat_FrictMat_FrictPhys()],
[Law2_ScGeom_FrictPhys_CundallStrack()]
),
GlobalStiffnessTimeStepper(active=1,timeStepUpdateInterval=100,timestepSafetyCoefficient=0.8),
triax,
TriaxialStateRecorder(iterPeriod=100,file='WallStresses'+table.key),
newton,
]
Gl1_Sphere.stripes=0
if nRead==0: yade.qt.Controller(), yade.qt.View()
triax.goal1=triax.goal2=triax.goal3=-10
while 1:
O.run(1000, True)
unb=unbalancedForce()
print 'unbalanced force:',unb,' mean stress: ',triax.meanStress
if unbtargetPorosity:
# we decrease friction value and apply it to all the bodies and contacts
compFricDegree = 0.95*compFricDegree
setContactFriction(radians(compFricDegree))
print "\r Friction: ",compFricDegree," porosity:",triax.porosity,
sys.stdout.flush()
O.run(500,1)
O.save('compactedState'+key+'.yade.gz')
print "###Compacted state saved ###"
triax.internalCompaction=False
setContactFriction(radians(finalFricDegree))
triax.stressMask = 5
triax.goal2=rate
triax.goal1=-10
triax.goal3=-10
newton.damping=0.1
print "gamma before deviatoric loading is", abs(triax.strain[1]-triax.strain[0])
print "click run to start small-strain deviatoric loading"
from yade import plot
def history():
plot.addData(e11=-triax.strain[0], e22=-triax.strain[1],
e33=-triax.strain[2],
