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About scott

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  1. Hi, Just wondering if anyone has overcome the issue of large file sizes in Crayfish? I've got a 4.5 Gb file that caused crayfish to crash. Appreciate any help. Cheers Scott
  2. scott

    Q Type Pits

    Apologies, the depth vs flow relationship got reformatted. See attached picture Cheers Scott
  3. scott

    Q Type Pits

    Hi Guys, Thanks for your advice, much appreciated. I have modelled the pits as suggested by tmashby and used the flags suggested by Bill and now have the model running and producing results. Upon inspection of the 2D results it appears to be acting the way I anticipate. I have attached 3 pictures: 1. Shows the model setup, I am blocking the house out with a z shape and have put pits and pipes into to drain the water that collects near the house (located in a small gully), the aim being to ensure floor level is protected (pits and pipes modelled with 50% blockage factor). (pic - house_drainage) 2. Shows the 2D results when there is no drainage (approx. average depth of ponding is 1m) (pic - no_drainage) 3. Shows the 2D results with the drainage (pic - with_drainage) However, upon inspection of the 1D results I was surprised to see very little/no flow through some of the pits even though there is enough depth to cause flow into the pits. The flow through the pits doesn't appear to match the depth/flow relationship I have specified for the majority of the pits. I have inspected the .eof file and found that the flow through the majority of the Q type pits is being reported as 'N' regime (at all time steps when there is flow in the pit), exercpt from manual below N Upstream controlled friction flow occurred in a Steep (S) channel with a Froude Number less than 0.5. N stands for normal flow, however, in this case the upstream controlled friction flow approach was adopted. This may occur during the transitioning of flow from downstream controlled to upstream controlled. If it occurs repetitively, the configuration of the channel should be reviewed. I have inspected the model setup and can't seem to find what would be causing this and haven't been able to identify anything. Does anyone have any suggestions? I am expecting the 2D results to look like they do but would like to see the 1D results validated in which case there should be more flow through the Q type pits. Does TUFLOW produce any results files to show the depth vs flow relationship during the run (there doesn't appear to be anything in the .eof? Below are the depth vs flow relationship , the first relationship for the 6 pits running north-south, and the second relationship for the pits running east-west at the northern end. Any advice would be appreciated. Depth Flow Depth Flow 0 0 0 0 0.013979 0.003131 0.01 0.002348 0.018128 0.005237 0.02 0.00664 0.021105 0.007006 0.03 0.012198 0.023509 0.008578 0.04 0.018781 0.02737 0.011354 0.05 0.026247 0.030488 0.013809 0.06 0.034502 0.033149 0.016046 0.07 0.043478 0.035494 0.018123 0.08 0.05312 0.037606 0.020075 0.09 0.063385 0.039538 0.021924 0.1 0.074237 0.041325 0.023677 0.12 0.116446 0.043002 0.025322 0.14 0.171862 0.046845 0.029061 0.16 0.234035 0.050326 0.032394 0.18 0.302297 0.053544 0.035421 0.2 0.376146 0.05656 0.038207 0.25 0.582799 0.062131 0.043224 0.3 0.817581 0.067236 0.04768 0.35 1.077453 0.07199 0.051714 0.4 1.311419 0.076465 0.055416 0.45 1.402596 0.080712 0.058849 0.5 1.488198 0.084767 0.062057 0.55 1.569136 0.092406 0.066629 0.6 1.6461 0.099536 0.069735 0.106261 0.072278 0.112651 0.074374 0.118758 0.076104 0.124621 0.077529 0.130273 0.078697 0.135737 0.079643 0.141034 0.080397 0.146179 0.080983 0.151189 0.081419 0.156073 0.081722 0.160843 0.081907 0.165508 0.081984 0.170074 0.081984 0.181106 0.081984 0.191654 0.081984
  4. scott

    Q Type Pits

    Hi, I am modelling some drainage improvements for a residential property within a larger catchment model. Grated cutoff drains are proposed to reduce runoff directed at the dwelling. I have created depth vs inflow curves and created Q type pits to model flow into these drains. Originally I tried connecting these pits to the 2D domain via SXS and SXG (conn_2D entry) but found neither selected the correct cells to match the proposed drain alignment. As can be seen in the attached plot my latest trial was using SX links to define the drain alignment and direct into the pits, but the results are not what is expected. It appears some water (very minor gets into the pipe) but the pit is bypassed and therefore the depth vs flow relationship is ignored. Has anyone else encountered this type of modelling? Or does anyone else have some additional ideas? Any help would be appreciated. Thanks
  5. Hi, I have discussed the approach of applying inflows from sub-catchment level (1d_bc regions) to all pits within the region with a number of other TUFLOW users and have found varying opinions regarding which pit types to include as connection from 1d to 2d ("SX" connections). Obviously Side Entry Pits allow for transfer of water from the pipe network to the surface but Junction Pits can also do the same (pit lids either blown off during large storm events or through pit lids having leaks/cracks). I thought I'd open it for some discussion and see what other thought regarding this. Cheers
  6. Hi, I am running a model to compare flows and depths in a channel pre and post flood mitigation works. The mitigation works direct more flow to this particular channel which is being modelled in 1D as an 'S' type channel. The 2D results clearly show that more flow arrives at the channel as expected, but upon inspection of the 1D results (TS output) it is a little less clearer. My question is how does TUFLOW calculate the maximum flow in a 1D channel element? Is it calculated at the upstream end, the downstream end or is an average flow calculated for the length? From my results it appears that it is either the upstream end or an average value. Any help would be appreciated. Cheers
  7. Thanks Bill and Parshin, problem solved! Part of the problem was due to the excessive number of characters. Cheers Scott
  8. Hi, I have been trying to make a copy of a TUFLOW model but it it doesn't appear to be quite doing what it should. The attached picture shows that the copy file was created, some of the text files are in there but the actual model files are not in there. Any suggestions? Anyone had the same problem? Cheers Scott
  9. scott

    Flow from 2D Cells

    Hi Phillip, Sorry for late reply. The model has since changed and as a result that flooding area is not of concern. However, I have attached the peak water levels points for you to have a look at, I'm still puzzled as to why that ponding would have occurred? Cheers Scott
  10. scott

    Flow from 2D Cells

    Thanks PHA the area is entirely same material type, road with smooth mannings roughness.
  11. scott

    Flow from 2D Cells

    Thanks Phillip, your interpretations are correct. I'm applying inflows as a 1d_bc layer with the hydrograph being split evenly across each of the 1d_pit and applied at the bottom of the pit. In this instance the pipe capacity is exceeded and overland flow results. I'm surprised to see the ponding given that there is no defined low point, there is a slight change in grade but still there is grade parallel and perpendicular to the alignment of the cells. Thanks
  12. scott

    Flow from 2D Cells

    Sorry, attached now.
  13. Hi, Attached is a screen shot showing a models 2D grid check and zpt check with a results layer overlayed (depth less than 50mm eliminated, and colour grading in 50mm intervals). I'm wondering why the model is calculating ponding in the middle of the page (darker blue with depth greater than 200mm)? Water is escaping the 1d_pit (green node at bottom right of the page). When looking at the heights in the zpt check file it is surprising to see that depth of ponding. I'm a bit rusty with how TUFLOW transfers water from cell to cell, so if someone could help explain this and why the ponding is occurring that would be great. Thanks
  14. Thanks Andy, I have tried the shallow depth stability factor without a lot of luck. I have tried the suggested range (0-10), the model becomes unstable at the same location. The only difference for the range of values being different mass errors and the time at which the model becomes unstable. Any other suggestions? Thanks Scott
  15. Hi, I think I am having trouble with the transition between 1D/2D boundaries in an open channel. In the attached files I was previously getting a similar problem as seen in the 2nd picture upstream of the bridge. I extended the width of the 1D area by a marginal amount and this helped solve the problem at this region, however, I am now getting the same problem upstream of the culvert. I have played around with width of the 1D region with little luck. Has anyone come across this problem? The model appears to be stable in the timestep procreeding the problem and therefore it doesn't appear to a problem with backwater effects (the water levels being reported at the problem area are in the order of 500m well above the DEM of 28m). Any suggestions would be appreciated. Cheers
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