WEBVTT 00:21.280 --> 00:23.819 Hi , my name is Doctor Tahira Sheri 00:24.120 --> 00:26.430 Lack and I'm a research hydraulic 00:26.440 --> 00:28.489 engineer here at the coastal and 00:28.500 --> 00:30.722 hydraulics lab at the Engineer Research 00:30.722 --> 00:32.819 and Development Center . Today , I'm 00:32.830 --> 00:34.886 going to be talking to you about the 00:34.886 --> 00:37.869 particle tracking model or PTM . The 00:37.880 --> 00:41.110 particle tracking model or PTM is a 00:41.139 --> 00:43.479 Lagrangian particle tracker that models 00:43.490 --> 00:46.360 transport processes such as infection 00:46.470 --> 00:49.799 diffusion deposition , et cetera to 00:49.810 --> 00:53.229 determine constituent fate . Lagrangian 00:53.990 --> 00:56.229 means that the point of reference for 00:56.240 --> 00:58.990 transport is the particles themselves . 01:00.259 --> 01:02.650 The model numerically solves at every 01:02.659 --> 01:05.300 time step . The location of a particle 01:05.309 --> 01:07.510 with specified properties within a 01:07.519 --> 01:10.449 given hydrodynamic flow field . The 01:10.459 --> 01:13.349 current particle types are sediment 01:13.489 --> 01:16.879 contaminant passive or water particles 01:16.889 --> 01:19.010 as well as biological particles . 01:21.010 --> 01:23.750 In the figure you see James River , 01:23.760 --> 01:26.809 Virginia and a sediment transport study 01:26.819 --> 01:30.809 result . For the animation , 01:30.919 --> 01:32.830 we can see particles moving in 01:32.839 --> 01:35.779 suspension are colored blue and 01:35.790 --> 01:38.169 particles that have been deposited are 01:38.180 --> 01:40.940 colored orange . That information can 01:40.949 --> 01:43.260 then be translated through analysis 01:43.269 --> 01:45.790 through to information like suspended 01:45.800 --> 01:48.022 sediment concentration , which is shown 01:48.022 --> 01:52.010 below . PTM was developed 01:52.019 --> 01:54.830 to allow users to efficiently and 01:54.839 --> 01:57.610 effectively determine the far field 01:57.620 --> 01:59.940 fate of constituents in complex 01:59.949 --> 02:03.459 hydrodynamic systems . This means that 02:03.730 --> 02:06.510 when particles are being transported . 02:06.730 --> 02:09.350 The hydrodynamics is not actually a 02:09.360 --> 02:11.490 part of the calculation it has been 02:11.500 --> 02:14.149 previously calculated and is used as 02:14.160 --> 02:17.740 input for PTM . This makes for a very 02:17.750 --> 02:20.149 efficient system because of that 02:20.160 --> 02:23.250 uncoupled hydrodynamic flow field . You 02:23.259 --> 02:26.279 can model several different scenarios 02:26.289 --> 02:30.050 for the same hydrodynamics . Also , we 02:30.059 --> 02:32.419 can look at modeling multiple sediment 02:32.429 --> 02:35.649 types . We can look at uh 02:35.710 --> 02:39.039 models , modeling specific source types . 02:39.059 --> 02:41.179 So you whether you're looking at a 02:41.190 --> 02:43.410 dredging scenario or whether you're 02:43.419 --> 02:46.119 looking at an erosion scenario . All of 02:46.130 --> 02:49.830 that is specified by the user . In 02:49.839 --> 02:53.259 addition , utilizing the S MS interface 02:53.270 --> 02:56.160 surface water modeling system interface 02:56.169 --> 02:59.020 visualization becomes user friendly . 02:59.029 --> 03:01.251 As you can see , we're looking at larva 03:01.251 --> 03:03.585 fish transport at Galveston Bay , Texas , 03:03.990 --> 03:07.259 uh sediment pathways or any pathways 03:07.270 --> 03:09.600 for particles are easy to identify . 03:10.389 --> 03:12.809 And then also we have post processing 03:12.820 --> 03:15.199 as I mentioned before of items like 03:15.210 --> 03:17.800 concentration deposition and so forth . 03:19.589 --> 03:22.259 There are many applications to using 03:22.270 --> 03:25.259 the particle tracking model . Some of 03:25.270 --> 03:28.380 our primary applications are within the 03:28.389 --> 03:30.679 dredging operations support . 03:32.199 --> 03:34.410 We look at fate of resuspended mere 03:34.419 --> 03:37.110 material during dredging and placement 03:37.410 --> 03:39.369 as well as risks to critical 03:39.380 --> 03:42.339 environmental receptors like oysters 03:42.350 --> 03:46.279 and coral . We also look at contaminant 03:46.289 --> 03:48.820 transport analysis where the particles 03:48.830 --> 03:51.889 have properties of contaminants and 03:51.899 --> 03:54.100 resonance time analysis determining 03:54.110 --> 03:56.970 flushing from systems which might be 03:56.979 --> 03:59.090 impacted to structures that are added 03:59.100 --> 04:02.179 or that might be potentially added . We 04:02.190 --> 04:04.750 want to determine pathway transport 04:04.759 --> 04:07.800 analysis . This might be looking at 04:07.809 --> 04:09.990 sediment and where it might go 04:10.000 --> 04:12.111 depending on if we're concerned about 04:12.111 --> 04:16.059 beneficial use or risk . And finally 04:16.070 --> 04:18.290 looking at biological transport like 04:18.299 --> 04:21.540 larval recruitment analysis , this 04:21.549 --> 04:25.399 might be uh the impact for of potential 04:25.410 --> 04:27.920 structures to the transport of larval 04:27.929 --> 04:31.450 fish in the right side of the 04:31.459 --> 04:33.820 screen . You can see core risk 04:33.829 --> 04:36.940 assessment and this was due to dredging 04:37.079 --> 04:39.839 at Opera Harbor , Guam . The dredging 04:39.850 --> 04:42.559 operation potentially would have an 04:42.570 --> 04:46.480 impact on coral reefs in the area . And 04:46.489 --> 04:48.809 you can see in the coral density map 04:48.820 --> 04:51.410 that the coral is directly adjacent to 04:51.420 --> 04:55.309 the potential dredging area . And so 04:55.320 --> 04:58.269 utilizing PTM and modeling sediment 04:58.279 --> 05:00.309 transport due to dredging , we were 05:00.320 --> 05:03.309 able to determine things like sediment 05:03.320 --> 05:05.149 accumulation during a dredging 05:05.160 --> 05:08.049 operation as well as suspended sediment 05:08.059 --> 05:11.299 concentration and deposition rate . All 05:11.309 --> 05:14.399 of that included with information of 05:14.489 --> 05:17.589 effect allowed us to determine 05:17.600 --> 05:21.549 risk to the coral . And in the right 05:21.559 --> 05:24.130 hand side , you can see the risk damage 05:24.140 --> 05:26.410 plot that we were able to develop . 05:26.420 --> 05:28.380 Where in green , you see where the 05:28.390 --> 05:30.910 coral would be safe in yellow , where 05:30.920 --> 05:33.031 the coral might be in danger and then 05:33.031 --> 05:35.750 red where we understand that due to the 05:35.760 --> 05:37.982 dredging operation , the coral would be 05:37.982 --> 05:41.640 destroyed . Here are some frequently 05:41.649 --> 05:44.720 asked questions about PTM . So the 05:44.730 --> 05:46.952 first thing that people want to know is 05:46.952 --> 05:50.119 how can they get PTM ? Well , PTM is 05:50.130 --> 05:52.339 available free of charge for all army 05:52.350 --> 05:54.517 Corp employees . So that's good . It's 05:54.517 --> 05:56.406 within the surface water modeling 05:56.406 --> 05:58.183 system , which is available for 05:58.183 --> 06:00.940 everyone . However , for non army Corps 06:00.950 --> 06:03.117 employees , you'll actually have to go 06:03.117 --> 06:06.019 to a to get more information and to 06:06.029 --> 06:09.809 actually access the model next they 06:09.820 --> 06:13.600 want to know , do I have to use S MS 06:13.609 --> 06:17.510 to use PTM ? The S MS environment is 06:17.519 --> 06:19.709 very user friendly and I definitely 06:19.720 --> 06:22.970 recommend that for new users , but PTM 06:22.980 --> 06:25.980 does work outside of S MS . However , 06:25.989 --> 06:27.989 the data analysis tools that create 06:27.989 --> 06:30.679 deposition and concentration and other 06:30.690 --> 06:33.790 analysis are actually a part of S MS . 06:33.799 --> 06:35.966 And if you want to utilize them , then 06:35.966 --> 06:38.021 you're gonna have to utilize S MS or 06:38.021 --> 06:41.459 create your own tools . Next , people 06:41.470 --> 06:43.660 ask , how long does it take for the 06:43.670 --> 06:45.892 model to run ? That's a good question . 06:46.100 --> 06:48.390 Well , unfortunately , there's no short 06:48.399 --> 06:50.720 answer for this . It really depends on 06:50.730 --> 06:52.730 the number of particles created the 06:52.730 --> 06:54.897 length of the simulation and the speed 06:54.897 --> 06:58.109 of your machine . So generally , we can 06:58.119 --> 07:00.341 say that for a two week simulation with 07:00.341 --> 07:03.619 50,000 particles on the average PC , 07:03.760 --> 07:05.927 then it should take less than a day to 07:05.927 --> 07:08.093 run . But for some people , this might 07:08.093 --> 07:10.420 be three or four hours and for others , 07:10.429 --> 07:12.839 it might be six or seven hours . It 07:12.850 --> 07:15.910 really depends on your specific machine 07:15.920 --> 07:19.760 and some other criteria , how 07:19.769 --> 07:22.299 can I learn to use the model ? This is 07:22.309 --> 07:25.799 also a great question . Personal PTM 07:25.809 --> 07:28.350 workshops are available upon request , 07:28.359 --> 07:30.859 just contact us and we're ready and 07:30.869 --> 07:33.220 willing to help you . But if you don't 07:33.230 --> 07:36.839 want an actual workshop . You can get 07:36.850 --> 07:38.961 more information about PTM and how to 07:38.961 --> 07:42.119 use the model at the listed website . 07:42.869 --> 07:45.399 This information might be documentation 07:45.410 --> 07:48.399 on how the model has been used before . 07:48.410 --> 07:51.339 It might be information on test cases 07:51.350 --> 07:53.359 and things like that . All of that 07:53.369 --> 07:55.390 should be available for you at that 07:55.399 --> 07:58.049 site and you can utilize that as sort 07:58.059 --> 08:01.399 of a first line of understanding PTM , 08:04.829 --> 08:08.589 er discovering , developing and 08:08.600 --> 08:10.711 delivering new ways to make the world 08:10.711 --> 08:12.829 safer and better every day .