A holistic microclimate model

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advanced_settings [2017/11/10 09:09]
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-====== Advanced Settings Panel ====== 
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-{{ ::​advanced_tab_small.jpg?​nolink |}} 
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-Different to all other panels, the Advanced Settings Panel is used to change the way ENVI-met works.\\ 
-Therefore you must be very careful when changing settings on this panel.\\ 
-We recommend to take notes, what has been changed in order to trace back the effects in your simulation. 
- 
-Normally the user must not change settings in this section. \\ 
-All settings have been tested and found to be the best working configuration for most of the typical simulation tasks.\\ 
-Look at this panel as a kind of service menu like on your TV set. However, it is known that people are very attracted by this kind of service panels, especially if they include red buttons. 
- 
-The next sections will tell you the meaning of the different settings on the Advanced Settings Panel. 
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-===== General and Compatibility Settings ===== 
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-=== Maximum Allowed Building Height (Default=100) === 
-Buildings above this height will be cut at the maximum height given here.\\ 
-The objective of this option is to keep Area Input File with the original building heights e.g. for skyscrapers and just cut them down in ENVI-met. 
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-=== Use small time steps for CO2 model (Default=No) === 
-Normally the CO2 system for the plant model can be handled like the other prognostic variables.\\ 
-It might be the case (e.g. if a huge amount of plants are in the area) that the CO2 model becomes unstable. 
-In this case, turn this option into "​Yes"​.\\ 
-In other cases, using small time steps will not change the model results, but increase the calculation time significantly. 
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-=== Use dynamic time steps (Default=Yes) === 
-The new option of dynamic time steps (see [[timesteps|[TIMESTEPS] Section]]) can be disabled here.\\ 
-For compatibility reasons only. 
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-=== Use longwave flux div in T-eqs (Default=Yes) === 
-Switches the longwave divergence term in the prognostic equation for air temperature off. For compatibility reasons only. \\ 
-(Simulations should not be made with different model versions!)\\ 
-For further information,​ look [[kb:​lwflux|here]]. 
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-===== Flow Model ===== 
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-=== Maximum of SOR Iterations === 
-Number of SOR Iterations in the flow solver. \\ 
-Should be kept like this but may be adjusted to a smaller number if using the continuous wind field calculation (see [[timing|[TIMING] Section]]). 
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-=== Maximum of Update Steps === 
-Number of iterations to find a stable wind field.\\ 
-May be adjusted to a larger number if flow problems occur.\\ 
-(See also [[kb:​flow|Knowledge Base: Flow Problems]]). 
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-===== Turbulence Model ===== 
-=== Use Buoyancy Term (Default=Yes) === 
-Allows to switch off the turbulence production through buoyancy forces.\\ 
-Might be helpful for certain low wind situations.\\ 
-**For a wind speed below 0.8 m/s, ENVI-met automatically turns //off// the buoyancy term.** 
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-=== Initial Relaxation (Default= 1.0) === 
-Sets the initial value of the [[relaxation]] coefficient.\\ 
-Reduce the value if problems with the TKE-e equation system occur constantly.\\ 
-See also [[kb:​turbulence|Knowledge Base Turbulence Model]]. 
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-=== Stationarity Criteria dK/dt (Default=0.010) === 
-Defines the threshold value of Km/dt below which further changes in the results are considered as numerical noise and the calculation is stopped to save time. 
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-=== Use Intelligent Troubleshooting === 
-Switches [[relaxation]] mechanism on or off.\\ 
-See also [[kb:​turbulence|Knowledge Base Turbulence Model]]. ​