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Heat and Mass Transfer UDF

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Old   August 8, 2005, 16:51
Default Heat and Mass Transfer UDF
  #1
Srinivas Parimi
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Hello all,

I hope you are all familiar with the heat and mass trasfer example provided in the Fluent advanced tutorials.

The UDF in it has a calculation of mass flow rate.

if(cell mixture temp. >= sat. temp.)

mass flow rate of liquid = -0.1*liquid VOF*liquid density* normalized liquid temp. from saturation temp.

I am kind of confused here to understand a few things...

1) Is the unit of VOF of that of volume? 2) what is the 0.1 in this equation mean?

Thanks in advance,

Srinivas Parimi
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Old   August 11, 2005, 22:08
Default Re: Heat and Mass Transfer UDF
  #2
Joey
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The unit of VOF is not volume, it is just a parameter without unit.

The parameter of "0.1" is time relaxation and has a unit of "1/s"

This formula comes from Wenhe Lee(1975) who is Chinese like me.
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Old   August 12, 2005, 00:33
Default Re: Heat and Mass Transfer UDF
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Srinivas Parimi
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Hello Joey,

Thank you for your response. If VOF has no units and 0.1 has units of 1/time, the dimensions dont add up on each sides of the equation. There is a volume term still missing.

Thanks in advance,

Srinivas Parimi
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Old   August 22, 2005, 13:49
Default Re: Heat and Mass Transfer UDF
  #4
Assefa Ayalew
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tutorials on conduction
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