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Custom density of water - rho(time)
Posted Nov 25, 2017, 7:52 a.m. EST Fluid & Heat, Materials Version 3.5a 2 Replies
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Hello everyone,
I'm using Comsol 3.5a. Is it possible to define a time dependent density also at steady-state (chemical engineering module-->momentum transport-->laminar flow-->incompressible Navier-Stokes)? For example, if I define (in expressions--> subdomain expressions):
rho=(1+exp(-t/1[s]))[kg/m^3]
I'll expect that, at steady state (t=+infinity), Comsol'll give me rho=1.
Thank you so much for your time.
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Hello Federica,
In a steady-state analysis, t does not take the value + infinity. You could assign t=some large number by defining it as a parameter, but it would just be easier to simply replace your expression that depends on t with the value you want. BTW, rho for water should be close to 1000[kg/m^3]¸ not 1[kg/m^3].
Best,
Jeff
-------------------Jeff Hiller
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Thank you so much Jeff.