A holistic microclimate model

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apps:biomet_utci [2015/12/22 22:25] – enviadminapps:biomet_utci [2015/12/22 22:26] – enviadmin
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 As the UTCI calculation expects the wind given at the 10 m level, ENVI-met BioMet uses the calculated local wind speed in the model domain related to the pedestrian level (zlevel) and scales it up to the  10 m level equivalent using the logarithmic wind power profile  As the UTCI calculation expects the wind given at the 10 m level, ENVI-met BioMet uses the calculated local wind speed in the model domain related to the pedestrian level (zlevel) and scales it up to the  10 m level equivalent using the logarithmic wind power profile 
-$$Wind_{10m} := ln(10 / z0) / ln(zlevel / z0) * Wind_(zlevel)$$+$$Wind_{10m} := ln(10 / z0) / ln(zlevel / z0) * Wind_{zlevel}$$
  
 In other word, if you calculate UTCI at some point for zlevel= 1.6 m, all ENVI-met data such as air temperature or radiative temperature will be used from this level, except of the wind speed which will be extrapolated to the 10 m level value. In other word, if you calculate UTCI at some point for zlevel= 1.6 m, all ENVI-met data such as air temperature or radiative temperature will be used from this level, except of the wind speed which will be extrapolated to the 10 m level value.
  
-Obviously, that doesn't make much sense as the $z0$ roughness value is unkown for most sites, but ENVI-met provides detailed and calculated wind flow data for all levels. +Obviously, that doesn't make much sense as the $z0$ roughness value is unknown for most sites, but ENVI-met provides detailed and calculated wind flow data for all levels. 
  
 ==== Final Remarks ==== ==== Final Remarks ====
-We do not recommend to use UTCI in the regression-based version based on using 2m (1.6m) level wind speeds extrapolated to 10m. In a complex urban environment, wind speeds at pedestrian level are unique and cannot be related to some above-roof general quantity.  Instead, we propose the application of a pure phxsically-based approach such as PET. PET is a much more open platform and the final outcomes are more or less the same for all static indicators. +We do not recommend to use UTCI in the regression-based version based on using 2m (1.6m) level wind speeds extrapolated to 10m. In a complex urban environment, wind speeds at pedestrian level are unique and cannot be related to some above-roof general quantity.  Instead, we propose the application of a pure physically-based approach such as PET. PET is a much more open platform and the final outcomes are more or less the same for all static indicators.