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Residuals aren't converging

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Old   April 8, 2024, 10:15
Default Residuals aren't converging
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Brendan
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Hi ,
I am currently trying to run simulations on a fin and streamline tube heat exchanger with 2 million cells and I am facing an issue with the residuals not converging.

Boundary Conditions
1. K-Epsilon Model
2. Air and Hydrogen-liquid
3. Mass Flow Inlet
4. SIMPLE
5. 1e-08
6. Hybrid Initialization
7. 2000 iterations

If anyone can let me know what can I do for better residuals would be really helpful
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File Type: jpg residuals.jpg (59.9 KB, 7 views)
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Old   April 11, 2024, 09:34
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Gert-Jan
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1. I would ask the Fluent Forum
2. What is your Re-number? K-epsilon is for high Re numbers. Better use SST.
3. Your flow problem will have transient features. You'll never be able to obtain a steady state solution.
4. If you want a steady state solution, limit you geometry to a very thin gap that slices the obstacles in half.
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Old   April 11, 2024, 09:55
Default Boundary Condition
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I used a mass flow inlet with the following variables..

Air
1. Mass Flow = 11.25
2. Gauge Pressure = 105700
3. Temperature = 344K

Hydrogen
1. Mass Flow = 0.1022
2. Gauge Pressure = 1571000
3. Temperature = 24K
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Old   April 17, 2024, 03:45
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What do you want to say with this reply?
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