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Old   January 17, 2006, 13:14
Default molecular properties
  #1
yann
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I tried to have the water density changing with both temperature and pressure, and so took the user database values. However, it says "insufficient dimmension for the molecular viscosity array". I solved the problem NCMAXV into NCMAX and all the others datas to be able to run the analysis. However, after I did it, the ouput given in a transient mode is absolutely wrong!! The density of water remains constant and equal to 1.2kg/m3 !!! What can I do? Is the user database wrong? It however looks right when we edit it!! Thank you in advance in you have a hint. Yann
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Old   January 18, 2006, 06:36
Default Re: molecular properties
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Mork
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Just a guess: Have you changed the cell material after defining a new material? Do you use liquid water or water vapour? How do you calculate the density?
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Old   January 18, 2006, 08:21
Default Re: molecular properties
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yann
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Dear Mork, that is effectively the first question to as, but yes, the cells are defined as liquid, and I am using liquid water. I am using the option: select material from database, then water(l), and then I tried to use "use internal properties calculation" which tells that the dimension array for viscosity is insufficient. What can I do? Create my own database? I also tried to use isobaric properties, defining the datum pressure as 997kg/m3, but the density doens't vary neither. Regards, Yann
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Old   January 18, 2006, 09:11
Default Re: molecular properties
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Richard
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When you have changed your set up, do you re-write the .geom file (to get a new parm.inc) and re-write the .prob file?
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Old   January 18, 2006, 12:52
Default molecular properties
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yann
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Thanks Richard,but yes I did rewrote both of them. Redards, Yann

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Old   January 18, 2006, 19:17
Default Re: molecular properties
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William Blake
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Are you using VOF? In that case you can only have constant densities for both fluids.

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Old   January 19, 2006, 05:33
Default Re: molecular properties
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yann
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Dear all, I resigned from my first idea to have the internal value for the water density. These value seem to be wrong...? I simply used the isobaric density for the water which is however less far convinient for the model I have to make. Anyway, thank you all for you help, and if ever someone knows the clue... Yann
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