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- | ====== Advanced Settings Panel ====== | ||
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- | {{ :: | ||
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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. | ||
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- | 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. | ||
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- | 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 " | ||
- | 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, | ||
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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: | ||
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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: | ||
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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: | ||