Known and resolved problems

This page provides a list of problems that have been discovered. They are grouped into known and resolved issues.

Table of Contents

 

Known: Wind field calculation for a terrain profile for the case ha < d0+z0

Problem:
2015-01-13

Applies to:
TALdia

Title:
Wind field calculation for a terrain profile for the case ha < d0+z0

Description:
Generally, the anemometer height ha should be set to a value larger d0+6*z0 such that specified value of the wind velocity does not fall inside the displacement layer, where the parameterisation of the meteorological boundary layer model relies on simple assumptions. For the case ha < d0+z0 it can occur that the weight factors av of the diagnostic procedure are not correctly calculated due to a mismatched temperature gradient that enters the Strouhal number, and the resulting flow field over the terrain profile is not calculated fully correctly. However, the case ha < d0+z0 should never occur if the parameter values are properly chosen.

Workaround:
Set the anemometer height ha if possible to a value larger d0+6*z0 but in any case to a value larger d0+z0.

Resolved:
-

 

Known: Low quality level can yield too low odor hour frequencies

Problem:
2004-10-04

Applies to:
AUSTAL2000 2.0.1 and higher

Title:
Low quality level can yield too low odor hour frequencies

Description:
If a dispersion calculation for an odorant is carried out with too low a quality level, giving rise to a high statistical uncertainty, the program yields odor hour frequencies that are systematically too low. This cannot be seen from the logged statistical uncertainty. The effect is smaller if nested grids are used because the larger mesh width reduces the statistical uncertainty. Thus, at larger source distances the frequency of odor hours is increased when increasing the mesh width. In contrast to concentration values, larger mesh widths can yield larger frequencies in the near field of sources. This effect has its origin in the definition of the odor hour.

Workaround:
1. The quality level should be sufficiently large, usually at least 0 or more. In case of doubts, a test run with a higher quality level should be performed to demonstrate that there is no substancial change in the results.
2. Nested grids should be applied under the careful consideration for which distance ranges the results of the individual grids are valid.

Note also the discussion in the Annex of the program description.

Resolved:
-

 

Resolved: Program error in a calculation with precipitation

Problem:
2014-04-02

Applies to:
TALdia 2.6.4

Title:
Program error in a calculation with precipitation

Description:
If TALdia is called via AUSTAL2000N or explicitly in a project with precipitation, the program aborts with an error message of the type "ri: parameter is unknown".

Workaround:
Comment the line "ri ?" in austal2000.txt, then call TALdia and afterwards uncomment the line before starting the dispersion calculation with AUSTAL2000N.

Resolved:
2014-09-03 (A2K 2.6.11, TALdia 2.6.5)

 

Resolved: German number format for the output (parameter "lc" = german and program call option "-Agerman")

Problem:
2013-01-11

Applies to:
AUSTAL2000 2.4 and 2.5

Title:
German number format for the output (parameter "lc" = german and program call option "-Agerman")

Description:
German number format (decimal comma instead of decimal point) can be requested for the output via parameter "lc" (value: german) or program call option "-Agerman". In a time series calculation, the program aborts in this case if it encounters a wind speed less than 0.75 m/s. The reason is an internal conversion of the minimum wind speed which is set in this case to 0.00 m/s instead of 0.70 m/s which later causes an error in the calculation of the friction velocity. In a AKS calculation, the same fault of the internal conversion may lead to a wrong handling of the anemometer position Xa, Ya, Ha.

Workaround:
Don't use parameter "lc" or program option "-Agerman" until this problem has been fixed.

Resolved:
2014-02-26 (version 2.6.9)

 

Resolved: Entry "cset" in the header of DMNA files on Windows systems

Problem:
2012-07-29

Applies to:
AUSTAL2000 2.4 and 2.5

Title:
Entry "cset" in the header of DMNA files on Windows systems

Description:
On Windows systems, AUSTAL2000 applies by default the language files A2K_en [at] latin1 [dot] nls and DIA_en [at] latin1 [dot] nls. This encoding (latin1/windows-1252) is used to save the text entries in the file header, in particular the units which contain non-ASCII characters. However, parameter "cset" in the file header contains as encoding information the value "UTF-8".

Workaround:
Ignore the information "cset" or change in the first line of file A2K_en [at] latin1 [dot] nls and DIA_en [at] latin1 [dot] nls the entry "nls/en/A2K_en" and "nls/en/DIA_en" to "nls/en/A2K_en@latin1" and "nls/en/DIA_en@latin1", respectively.

Resolved:
2014-02-26 (version 2.6.9)

 

Resolved: Several parallel calculations applying cooling tower plume rise (VDISP)

Problem:
2003-02-14

Applies to:
AUSTAL2000 1.0.1 and higher

Title:
Several parallel calculations applying cooling tower plume rise (VDISP)

Description:
In determining plume rise according to VDI 3784/2 (cooling tower), AUSTAL2000 invokes the external program VDISP; it works with the two files VDIIN.DAT and VDIOUT.DAT in the AUSTAL2000 home directory. If two or more AUSTAL2000 calculations are run in parallel, the access to these files may interfere, leading to wrong plume rise estimates.

Workaround:
Carry out only one AUSTAL2000 run at a time if VDISP is involved.

Resolved:
2014-02-26 (version 2.6.9)

 

Resolved: NOSTANDARD option PRFMOD and AKS

Problem:
2011-09-12

Applies to:
AUSTAL2000 2.5.0

Title:
NOSTANDARD option PRFMOD and AKS

Description:
NOSTANDARD option PRFMOD is not recognized if a dispersion class statistics (AKS) is applied.

Workaround:
Explicit setting of the modified boundary layer version with the NOSTANDARD option "Blm=4.6".

Resolved:
2011-09-12 (version 2.5.1)

 

Resolved: Grid localization of monitor points in nested grids

Problem:
2011-07-29

Applies to:
AUSTAL2000 to 2.4.7

Title:
Grid localization of monitor points in nested grids

Description:
The two outer cell rows of an inner grid should not be used for assessments.  Therefore monitor points located in these rows are localized in the next coarser grid. However, if the monitor point is exactly at the inner edge of the second outer row, it is localized by AUSTAL2000 in this inner grid.

Workaround:
If required, shift the monitor position by a small amount.

Resolved:
2011-08-03 (version 2.5.0)

 

Resolved: Project title (ti) with more than 140 characters

Problem:
2011-04-13

Applies to:
AUSTAL2000 to 2.4.7

Title:
Project title (ti) with more than 140 characters

Description:
A project title (parameter ti) with more than about 140 characters causes internal problems, in all cases known to us in a program abort at the end of the dispersion calculation.

Workaround:
Use project titles (ti) with less than 140 characters.

Resolved:
2011-08-03 (version 2.5.0)

 

Resolved: Specifications in the file header of time series with the statistical uncertainties at monitor points

Problem:
2009-04-17

Applies to:
AUSTAL2000 2.4.4 to 2.4.7

Title:
Specifications in the file header of time series with the statistical uncertainties at monitor points

Description:
For substances beside odourants the unit stated in the file header (parameter unit) should be "1" and not "%" because the time series contains the relative, i.e. dimensionless scatter. For odourants the unit "%" is correct as here the absolute scatter of the odour hour frequency is listed, and the latter is always given in percent; but here the format specification (parameter form) is not correct: it should read "sct%6.1f" instead of "dev%(*100)6.1f", the values listed further below are however correct.

Workaround:
Note these comments when evaluating the time series of statistical uncertainties.

Resolved:
2011-08-03 (version 2.5.0)