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Old   August 29, 2009, 07:08
Default Scalar Transport
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Dear all,

I'm interested to know why one would you a dimensionless scalar to model concentration. Could you clarify how if this could be used to represent dye in water for example? Given I only know the dye is completely of neutral buoyancy...

Thanks
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Old   August 29, 2009, 11:12
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My simulation involves a dye released from a point source at 0.01kgs^-1 within a room filled with air. Making it a specified scalar and hence dimensionless doesn't quite convince me, but I don't know the density of this dye. Any ideas?
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Old   August 30, 2009, 07:07
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I am not sure exactly what you are asking - but isn't a natural unit for dye concentration kg of dye/kg of mixture - so kg/kg and therefore dimensionless.
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Old   August 30, 2009, 09:23
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Quote:
Originally Posted by ghorrocks View Post
I am not sure exactly what you are asking - but isn't a natural unit for dye concentration kg of dye/kg of mixture - so kg/kg and therefore dimensionless.
Thanks ghorrocks. That seems good. Is there a way of calculating parts per million or some other volumetric concentration given that 0.01kgs^-1 are injected and there is always a constant volume within the vessel?
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