1D Bridges: Difference between revisions

The following section looks at bridges using the 1D component of TUFLOW. Reference should also be made to Section 5.7.2 of the <u>[https://downloads.tuflow.com/_archive/TUFLOW/Releases/2018-03/TUFLOW%20Manual.2018-03.pdf 2018 TUFLOW Manual]</u>. For information on bridges in the 2D domain see <u>[[TUFLOW_2D_Hydraulic_Structures | 2D Hydraulic Structures]]</u> and <u>[[Tutorial_M11#Part_2_-_1D_Open_Channel_with_1D_Bridges_and_Weir_inflow_.282D.29_and_Outflow_.281D.29Tutorial M04|Tutorial ModuleM04 11- Tuflow]]</u>. Example models using bridges in 1D and 2D are available in the [[TUFLOW Example Models#Structures|TUFLOW Example Model Dataset]].<br>

Adjustment of losses according to approach/departure velocities is the default from 1D channel to 1D bridge to 1D channel. However, for TUFLOW Builds prior to 2020-10-AA, if the BB bridge is linked directly to a 2D domain (typically via a SX link), there is no adjustment of entrance / exit losses on the sides connected to the 2D. This capability was introduced for 2D channel to 1D bridge to 2D channel in Build 2020-10-AA and onwards, and losses can be automatically adjusted based on the approach/departure 2D velocities across the SX connections by setting "<font color="blue"><tt>Structure Losses SX</tt></font> <font color="red"><tt>==</tt></font><tt> ADJUST</tt>" (see Section 6.2 of the <u>[https://downloads.tuflow.com/TUFLOW/Releases/2020-10/TUFLOW%20Release%20Notes.2020-10-AF.pdf 2020-10 Release Note]</u>). For B bridges the default is not to adjust losses (refer to the <u>[https://downloadsdocs.tuflow.com/_archiveclassic-hpc/TUFLOWmanual/Releaseslatest/2018-03/TUFLOW%20Manual.2018-03.pdf 2018 TUFLOW Manual]</u> for more information). In the case of 2D connections, refer to the links below for a discussion on the intricacies and challenges of taking into account contraction and expansion losses for 1D structures connected directly to 2D domains:

<li>Create a 1d_tab HW (height vs width) .csv file for each standard shape (iei.e. set up a database of the irregular shapes). For the height value you can start at a value of zero so that height becomes depth (this might making the .csv files easier). As the height increases the width changes to reflect the particular irregular shape you are modeling. In the example below, the width at the top of the arch (2.1m) is set to a small value of 0.001m as opposed to zero as the HW becomes NA past the top of the irregular shape. <br>

<li>Any number of 1d_tab lines can reference the same .csv file, iei.e. you don't need to have a unique .csv file for every 1d_tab line. <br>

<br><br><br><br><br><br><br><br><br><br>

<br><br><br><br><br><br><br><br><br>

|uplink=[[ TUFLOW_1D_Hydraulic_StructuresTUFLOW 1D Channels and Hydraulic Structures | Back to 1D Channels and Hydraulic Structures]]