Dear iRIC experts
may I have some suggestions from you about my simulation result (Picture was attached). I was satisfied with flood propagation at the upstream part of the river, but at the downstream of the river (green line is the river), it was very terrible, there is no any flow through the downstream river. so I think because of my DEM (12.5m resolution) is not very good, but I can not judge, because I am a new iRIC user. also I wondering it might be caused by other factors. your suggestion will be very useful for my research, thank you very much.
khanvixay
コメント
Hello,
I think your DEM is rough for the purpose of your calculation.
I seggest that you try Increasing discharge or using fine DEM(5m resolution etc).
Regards,
Thank you very much for your kind suggestion. as i check my study area there is only DEM 12.5m is the highest resolution ( 14°44’31.52″N. 106°29’10.98″E ), could you please tell me where i can download more DEM high resolution or i have to purchase ?. if i have to purchase DEM 5m or 2.5m where i can purchase ?. thank you very much.
khanvixay
Because riverbed topography under the water surface is not included in the DEM measured by LIDAR, it is necessary to combine the bathymetry date and DEM if you want to simulate the river flow accurately. If you do not have bathymetry data, accurate simulation is difficult. What is the size of the calculation grid? If you reduce the grid size, the simulation may improve a little.
Thank you very much inoue-t for very good suggestion. for my calculation grid is dj 257m x di257m (W 18000. nj 70. ni 200) (create grid from polygonal line and width). when i reduce the calculation grid dj 12.5 m x di13 m but when i do map geographic data to grid attributes is not completed (not responding) even left it do map geographic data for 48 hours.
now i separate my research area to two parts and my calculation grid is dj 13m x di13.5m (W 30000. nj 2300. ni 1800) (create grid from polygonal line and width) when i do map geographic data to grid attributes is not completed (not responding) also, from now i left it do map geographic 24 hours and still not complete.
so i would like to know the reason why is not complete?. i would like to know the limitation of grid creation of the model as well.
thank you very much for your kind helping
introduce my name is fekis from indonesia
what is the difference between the upwind scheme and the CIP Method
Hello, thank you for using iRIC.
> so i would like to know the reason why is not complete?.
I guess that some part of area where you are generating a grid has no DEM data.
In such cases, attribute mapping is slow.
Please download the file below. I guess the situation with you is something like this.
https://www.dropbox.com/s/xt7gizc5o08pyes/sample1.ipro?dl=0
To make it fast, you can add points with high elevation, so that whole area has elevation data.
The following is the sample data that I’ve added several points. With this data, attribute mapping is much faster.
https://www.dropbox.com/s/f5w0psod1ynfrqt/sample2.ipro?dl=0
You can know how to add points from the following URL.
https://iric-gui-user-manual.readthedocs.io/en/latest/04/04/03_pointset_data.html#add-new-point-a
After adding points, please remember to remesh TIN before generating grid.
https://iric-gui-user-manual.readthedocs.io/en/latest/04/04/03_pointset_data.html#remesh-tins-t
You can check if the DEM data covers the whole area, by switching
[Display Setting] from [Points} to [Surface].
https://iric-gui-user-manual.readthedocs.io/en/latest/04/04/03_pointset_data.html#display-setting-s
Thanks,
thank you very much Keisuke san, you told me very detail and my slow mapping might be solve, you are right some part of grid outside of DEM.