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| kb:turbulence [2013/05/12 17:51] – external edit 127.0.0.1 | kb:turbulence [2022/04/04 19:24] – [Turbulence Model in ENVI-met] enviadmin | ||
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| As the result of the TKE-ε equation Km (via Ke and directly) is used as input data for the next calculation cycle, there is a non-linear feedback loop between the turbulent exchange coefficient and the TKE-ε equation. Once Km begins to be unstable, the TKE-ε equation system will get unstable too, producing even more unstable Km's in the next loop.\\ | As the result of the TKE-ε equation Km (via Ke and directly) is used as input data for the next calculation cycle, there is a non-linear feedback loop between the turbulent exchange coefficient and the TKE-ε equation. Once Km begins to be unstable, the TKE-ε equation system will get unstable too, producing even more unstable Km's in the next loop.\\ | ||
| - | To avoid numerical problems, several mechanisms have been introduced in ENVI-met making the turbulence model more reliable: | ||
| - | |||
| - | * [[Two-Step Calculation Loops (Initialisation)]] | ||
| - | * [[Intelligent Troubleshooting via Relaxation]] | ||
| - | * [[Range Limiting]] | ||
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| - | In previous ENVI-met versions, it was suggested to calculate the turbulence field using the " | ||
| - | Today, we do not suggest to use the " | ||
| - | Recent computers are strong enough to use the " | ||
| - | **As the old update method was a huge source of error and frustration, | ||
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