Using the Z-model for Delft3D flowUsing the Z-model for Delft3D flowhttps://oss.deltares.nl/c/message_boards/find_thread?p_l_id=1806675&threadId=2710442021-03-01T23:37:25Z2021-03-01T23:37:25ZRE: Using the Z-model for Delft3D flowQinghua Yehttps://oss.deltares.nl/c/message_boards/find_message?p_l_id=1806675&messageId=2723592013-05-02T08:41:56Z2013-05-02T08:41:56ZHi Shawn,<br /><br />For z model in present version of Delft3D, the cutting cell algorithm is already included to deal with the irregularities of horizontal boundary. If you choose Flooding scheme for horizontal advection, it is on.<br /><br />As to the layer thickness, it depends on your focus.<br /><br />As to your claim that 10 layers z-model gives out worse results than sigma model, I can imagine. Since in sigma model, you have 10 layers everywhere in the computational domain, but in z layer model, you probably don't have 10 layers everywhere. The layer thickness in z layer is roughly computed as (ztop-zbot)/10. The ztop should be as high as the possible highest water surface level. Thus usually the layer thickness in z-layer model is thicker than sigma layers. So you get lower vertical resolution in z-layer model if you set the same layer number as the sigma-layer model. In summary, you need more layers for z-layer model to get the same resolution in general.<br /><br />Hope this will help a bit.<br /><br />QinghuaQinghua Ye2013-05-02T08:41:56ZUsing the Z-model for Delft3D flowShawn Simhttps://oss.deltares.nl/c/message_boards/find_message?p_l_id=1806675&messageId=2710432013-04-29T08:23:34Z2013-04-29T08:23:34ZHi all,<br /><br />I would like to use the Z-model on my computational domian. I have tried using it for a 10 layer model, however the results I obtained are much poorer than what I obtained using the sigma model. <br /><br />I can briefly describe my domain. 14 m (x-dir), 4 m (y-dir), dx = 0.005 m , dy = 2 m, water depth = 0.35m. <br />The coastal topography that comprise composite slopes is as folows, offshore 0 to 6m (no bottom contour),--> 6 to 6.17 m (slope of 1(V):0.68(H)) --->6.17 to 7.67 m (slope of 1:15)---> 7.67 to 14 m (slope of 1:30)<br /><br />I am trying to find out the maximum inundation distance under solitary waves of different wave heights and compare it with experimental results.<br /><br />So here are some of my questions:<br /><br />1) Is it advisable to use the 'cut cell' option and if so, how should I go about doing it?<br />2) What is a recommeded number of layers that I should use? and should all layers have the same thickness? I have seen test cases with equal thickness and unequal thickness used.Shawn Sim2013-04-29T08:23:34Z