The role of UnifFrictCoef1D https://dlt-acc.firelay.cloud/en/c/message_boards/find_thread?p_l_id=4041874&threadId=4393497 2026-05-12T16:52:09Z 2026-05-12T16:52:09Z Jing Zhao https://dlt-acc.firelay.cloud/en/c/message_boards/find_message?p_l_id=4041874&messageId=4393557 2017-06-30T11:31:53Z 2017-06-30T11:31:53Z

Dear Ludmila,<br /><br />For your question, &#34;UnifFrictCoef1D&#34; is uniform friction coefficient on 1D links, and &#34;UnifFrictCoef&#34; is uniform friction coefficient on 2D links.<br /><br />Kind regards,<br />Jing Zhao<br /><br />Deltares

Jing Zhao 2017-06-30T11:31:53Z Ludmila Rechiman https://dlt-acc.firelay.cloud/en/c/message_boards/find_message?p_l_id=4041874&messageId=4393511 2017-06-23T20:32:03Z 2017-06-23T20:32:03Z

Hello Jing Zhao,<br /> thank you for your reply. In most of the parts of the mesh there is not 1D flow links. I would like to know the meaning of the UnifFrictCoed1D. Why is different from UnifFrictCoef?<br /><br />Thank you

Ludmila Rechiman 2017-06-23T20:32:03Z Jing Zhao https://dlt-acc.firelay.cloud/en/c/message_boards/find_message?p_l_id=4041874&messageId=4393509 2017-06-23T15:31:43Z 2017-06-23T15:31:43Z

Dear Ludmila:<br /><br />Thank you for your post. We have two questions for you:<br /><br />1. Does your network include 1D links? If so, how did you add 1D links?<br />2. Comparing with your first simulation which gives results in attachment 1, could you double check, in your second simulation, did you <strong>only</strong> changed &#34;UnifFrictCoef1D&#34; in the settings of MDU and external files?<br /><br />Looking forward to your reply. <br /><br />Kind regards,<br />Jing Zhao<br /><br />Deltares

Jing Zhao 2017-06-23T15:31:43Z Ludmila Rechiman https://dlt-acc.firelay.cloud/en/c/message_boards/find_message?p_l_id=4041874&messageId=4393496 2017-06-21T00:01:32Z 2017-06-21T00:01:32Z

Hello,<br /> I am new using dflowfm and I am exploring the Roughness role in a simulation of a delta. The .mdu file has two parameters: UnifFrictCoef and UnifFrictCoef1D. I have changed the Manning value from the GUI interface. Only the value UnifFricCoef is modified and give me the expected results (see attachment 1-). When I modified the value of UnifFrictCoef1D to be equal than UnifFrictCoef I get a funky behavior (see attachment 2-). I would like to know which is the role of UnifFrictCoef1D? The manual said that is &#39;&#39;Uniform friction coefficient in 1D links,&#34; but I do not understand. Perhaps you have a clear idea of the meaning.<br /><br />Thank you in advance

Ludmila Rechiman 2017-06-21T00:01:32Z