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alinematollahi October 5, 2010 07:01

non-newtonian model
 
Hi
I'm going to a non-Newtonian models for blood do I use the models caro and casson. When the models for the following phrases (in cfx expression language)and I'll solve the problem, not a correct answer that it review the resulting graphs can be realized. When the models in the software I use, firstly when entering model casson
and begin to solve it is removed from the solver and Gives the following message. Do phrases are correctly expressed? And how do I use casson model?</SPAN></SPAN></SPAN>
casson model in CEL:(sqrt(tawy/abs(min(uppers,max(sstrnr,lowers))))+sqrt(miuc))^2
tawy:6.7253e-04[kg m^-1 s^-2]
miuc:0.008[kg m^-1 s^-1]
uppers:300[s^-1]
lowers:0.00001[s^-1]
caro model in CEL:miubin+((miuzero-miubin)*(1+(a*((min(uppers,max(sstrnr,lowers))) ^2)))^n)
miubin:0.007888[kg m^-1 s^-1]
miuzero:0.12805[kg m^-1 s^-1]
uppers:300[s^-1]
lowers:0.00001[s^-1]
error in casson (Models in software):
Details of error:-
----------------
Error detected by routine DELDIR
CDRNAM = get_VISCDYN
CRESLT = NONE

Current Directory : /FLOW/SOLUTION/TSTEP0/CLOOP0/ZN1/VERTICES/GLOBAL/MINIMUM

Details of error:-
----------------
Error detected by routine MAKDAT
CDANAM = LVAR CDTYPE = INTR ISIZE = 77
CRESLT = OLD

Current Directory : /FLOW/ALGORITHM/ZN1/SYSTEM/VARIABLES

thank you very much

michael_owen October 6, 2010 17:57

Quote:

Originally Posted by alinematollahi (Post 277866)
Hi
I'm going to a non-Newtonian models for blood do I use the models caro and casson. When the models for the following phrases (in cfx expression language)and I'll solve the problem, not a correct answer that it review the resulting graphs can be realized. When the models in the software I use, firstly when entering model casson and begin to solve it is removed from the solver and Gives the following message. Do phrases are correctly expressed? And how do I use casson model?</SPAN></SPAN></SPAN>
casson model in CEL:(sqrt(tawy/abs(min(uppers,max(sstrnr,lowers))))+sqrt(miuc))^2
tawy:6.7253e-04[kg m^-1 s^-2]
miuc:0.008[kg m^-1 s^-1]
uppers:300[s^-1]
lowers:0.00001[s^-1]
caro model in CEL:miubin+((miuzero-miubin)*(1+(a*((min(uppers,max(sstrnr,lowers))) ^2)))^n)
miubin:0.007888[kg m^-1 s^-1]
miuzero:0.12805[kg m^-1 s^-1]
uppers:300[s^-1]
lowers:0.00001[s^-1]
error in casson (Models in software):
Details of error:-
----------------
Error detected by routine DELDIR
CDRNAM = get_VISCDYN
CRESLT = NONE

Current Directory : /FLOW/SOLUTION/TSTEP0/CLOOP0/ZN1/VERTICES/GLOBAL/MINIMUM
Details of error:-
----------------
Error detected by routine MAKDAT
CDANAM = LVAR CDTYPE = INTR ISIZE = 77
CRESLT = OLD

Current Directory : /FLOW/ALGORITHM/ZN1/SYSTEM/VARIABLES
thank you very much

This is a bug. I have run into it. When you attempt to use one of the built in non-Newtonian viscosity models, it is not calculating the Dynamic Viscosity. You will have to create the model from CEL and just enter in the Dynamic Viscosity field in the material definition. I had to do this for the Cross model. Luckily all of the equations for the various models are well documented, so they are easy to recreate.

alinematollahi October 19, 2010 06:09

thank you michael_owen
Please you are right. But when casson model in its software that I use the numbers assigned to give error messages
tawy:6.7253e-04[kg m^-1 s^-2]
miuc:0.008[kg m^-1 s^-1]
uppers:300[s^-1]
lowers:0.00001[s^-1]

error in casson (Models in software):
Details of error:-
----------------
Error detected by routine DELDIR
CDRNAM = get_VISCDYN
CRESLT = NONE

Current Directory : /FLOW/SOLUTION/TSTEP0/CLOOP0/ZN1/VERTICES/GLOBAL/MINIMUM
Details of error:-
----------------
Error detected by routine MAKDAT
CDANAM = LVAR CDTYPE = INTR ISIZE = 77
CRESLT = OLD

Current Directory : /FLOW/ALGORITHM/ZN1/SYSTEM/VARIABLES
thank you very much

alinematollahi October 19, 2010 06:09

non-newtonian fluid-casson model
 
thank you michael_owen
Please you are right. But when casson model in its software that I use the numbers assigned to give error messages
tawy:6.7253e-04[kg m^-1 s^-2]
miuc:0.008[kg m^-1 s^-1]
uppers:300[s^-1]
lowers:0.00001[s^-1]

error in casson (Models in software):
Details of error:-
----------------
Error detected by routine DELDIR
CDRNAM = get_VISCDYN
CRESLT = NONE

Current Directory : /FLOW/SOLUTION/TSTEP0/CLOOP0/ZN1/VERTICES/GLOBAL/MINIMUM
Details of error:-
----------------
Error detected by routine MAKDAT
CDANAM = LVAR CDTYPE = INTR ISIZE = 77
CRESLT = OLD

Current Directory : /FLOW/ALGORITHM/ZN1/SYSTEM/VARIABLES
thank you very much

berelian90 October 19, 2010 07:39

Dear Mr. nematollahi,
are you from iran?
i have used ansys cfx 12 for modeling an artery bifurcation in fsi
and i will be so grateful if you help me.
this is my email address:
zahra_farashah@yahoo.com


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