Changes between Version 491 and Version 492 of doc/app/errmsg

Timestamp:

Mar 15, 2018 4:23:31 PM (7 years ago)

Author:

gronemeier

Comment:

--

doc/app/errmsg

@@ -242 +242 @@
 ||[=#PA0200 PA0200]   ||missing dz   || No value for [../inipar#dz dz] was given in the parameter file. ||
 ||[=#PA0201 PA0201]   ||dz=... <= 0.0   || The value given for [../inipar#dz dz] must be greater than 0.0. ||
-||[=#PA0202 PA0202]   ||grid anisotropy exceeds threshold given by only local horizontal reduction of near_wall mixing length l_wall starting from height level k = ... .   ||This is just a warning. It tells you that during the initialization of the near-wall mixing length {{{l_wall}}} which is important for the [/wiki/doc/tec/sgs turbulence closure] the grid-dependent mixing length {{{l_grid}}}='''''Δ''' = (Δx Δy Δz)^1/3^'' becomes relatively large. This might result in untrustworthy result. The reason for a large value of {{{l_grid}}} is the grid anisotropy. To avoid this message it is probable that you have to change your settings for [../inipar#dz_stretch_level dz_stretch_level] or [../inipar#dz_stretch_factor dz_stretch_factor].   ||  ||
+||[=#PA0202 PA0202]   ||grid anisotropy exceeds threshold given by only local horizontal reduction of near_wall mixing length l_wall starting from height level k = ... .   ||The grid-dependent mixing length {{{l_grid}}} ( ''= '''Δ''' = (Δx Δy Δz)^1/3^'' ) becomes larger than the near-wall mixing length {{{l_wall}}} starting from the reported height level {{{k}}}. Although PALM will not abort due to this warning, the chosen grid setup might lead to untrustworthy results. The reason for this is an unfavourable choise of grid anisotropy. To avoid this, make sure that the values of [../inipar#dx dx], [../inipar#dy dy], and [../inipar#dz dz] do not differ too much from each other. In case of grid stretching, the settings of [../inipar#dz_stretch_level dz_stretch_level] and/or [../inipar#dz_stretch_factor dz_stretch_factor] should be changed to ensure a smaller difference between {{{dz(k)}}} and {{{dx}}} and {{{dy}}} at the reported height level. ||
 ||[=#PA0203 PA0203]   ||inconsistent building parameters: bxl=... bxr=... bys=... byn=... nx=... ny=...    || The setup of the single building ([../inipar#topography topography] = '' 'single_building' '') yields a too narrow building or the building walls are positioned outside of the model domain. Please check the [../inipar#topo building parameters] in your parameter file. ||
 ||[=#PA0204 PA0204]   ||no street canyon width given   || If [../inipar#topography topography] = '' 'single_street_canyon' '' is given, also a canyon width must be given by either specifying [../inipar#canyon_width_x canyon_width_x] or [../inipar#canyon_width_y canyon_width_y] in the parameter file. ||