Changes between Version 42 and Version 43 of doc/tec/bc
- Timestamp:
- Nov 4, 2017 7:22:49 AM (7 years ago)
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doc/tec/bc
v42 v43 133 133 === Method 2: Newton iteration / lookup table === 134 134 135 Alternatively, the Obukhov length can be calculated by solving an implicit equation relating the ''L'' to the bulk Richardson number. This can be achieved either by a Newton iteration algorithm ({{{most_method = 'newton'}}}) or by using a lookup table ({{{most_method = 'lookup'}}}). Note that the latter is the new default in PALM as it is much faster than the Newton iteration method and the results are more precise compared to the circular method. However, it can only be used when the roughness lengths are homogeneously set on each processor.135 Alternatively, the Obukhov length can be calculated by solving an implicit equation relating the ''L'' to the bulk Richardson number. This can be achieved either by a Newton iteration algorithm ({{{most_method = 'newton'}}}) or by using a lookup table ({{{most_method = 'lookup'}}}). Note that the latter is faster than the Newton iteration method and the results of both methods are more precise compared to the circular method. However, it can only be used when the roughness lengths are homogeneously set on each processor. 136 136 137 137 Both methods require a different sequential order to derive the surface fluxes:
