TUFLOW Version Backward Compatibility: Difference between revisions

 

=Backward Compatibility Change Register=

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| The new defaults will produce different results. For established models run using the 2005-05-XX builds, use <font color="blue"><tt>Defaults </tt></font> <font color="red"><tt>== </tt></font><tt> PRE 2006-06-AA</tt> to use the previous default settings. Each of the new default settings and their affects are discussed in the rows below.

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| The most pronounced effect of the shallower wet/dry depths is likely to occur in areas that are still filling at the flood peak, such as behind a levee that is only just overtopped. The shallower wet/dry depths provides a greater flow depth for a longer period over the levee.

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| May select slightly different cells along boundary/link lines. This may cause a difference where the line is along the top of levee, possibly creating a “hole” in embankment.

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| Can have a significant effect where the viscosity term is influential. This occurs where the friction term is less dominant (i.e. low Manning’s n and/or deeper water such as the lower, tidal, reaches of rivers).

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| Can have a significant affect in the vicinity of structures within a 1D network and for culvert networks. Does not affect 1D structures linked to a 2D domain or at the structure ends not connected to another 1D channel.

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| Usually negligible effect unless the model storage is predominantly within 1D closed sections (i.e. B, C and R channels). The 1D domain is likely to be more sensitive to instabilities due to the much smaller storage above the top of the closed sections, therefore, a smaller 1D timestep may be required and/or the Storage Above Structure Obvert (%) increased.

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| No effect as previously the model would have become “unstable” as the trigger for an instability was the top of the channel/node.

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| Usually only minor effects plus improved stability.

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| Minor influence.

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| Negligible influence plus improved stability. However, note the different treatment of energy losses once the bridge deck obvert/soffit is submerged if a BG or LC table is specified.

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| Only affects the presentation of results. Note, that Method A is no longer recommended or supported.

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Does not affect hydraulic calculations, however, if a Blank, B or W channel is now lowered/raised because the inverts are now used, this will affect results/stability - see note at end of Apply All Inverts).

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| Will affect results as ALL PARALLEL can be around 10% more “slippery” than CHANGE IN RESISTANCE. For calibrated or established models developed using build prior to Build 2006-06-AA , recommend setting to CHANGE IN RESISTANCE

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| Negligible effect.

 

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|'''Builds prior to 2006-06-XX'''

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