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-   -   Problem in Axial turbine stage NonEquilibrium Calculation (https://www.cfd-online.com/Forums/cfx/169555-problem-axial-turbine-stage-nonequilibrium-calculation.html)

bharath April 13, 2016 00:38

Problem in Axial turbine stage NonEquilibrium Calculation
 
Hi to all
I am doing simulation for Axial turbine (Steam turbine) Last Stage Blade Non Equilibrium calculation using IAPWS table.

1)For Droplet Condensation, I used MUSIG approach for different size particle diameters (1µ to 20 µ). While doing post processing, I found that steam(liquid) temperature (Tl) is more than steam (Vapor) temperature (Tv). Tl > Tv

2) However when using small droplets model Steam (liquid) temperature is less than Steam (Vapor) temperature. Tl < Tv and I think this is right.

Why Tl > Tv in MUSIG approach? Could any body help me regarding this issue.
Thanks in advance





bharath April 19, 2016 00:15

Hi,

After further study I found the reason for this.

At first in both models Tl>Tv.(i.e) steam (liquid) temperature is greater than Steam (gas) temperature. Previously, I noted it wrong.

Steam (gas) is in super cooled state (otherwise metastable region) Tl is greater than the Tv. This is possible in meta stable regions and nucleation barrier is stopping steam (gas) to convert into liquid.

Thank you all.


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