Parking lot test

[Sadegh Dalfardi]

Hello

I gonna do parking lot test to ensure my dem based streams are correct or not? I produced my slopes in x and y direction by both priority flow (R package by Lura Condon) and by pftool commands. i want to know besides slope files ( in X and Y directions) and assign manning cofficient do i need pressure file also? I think i should define pressure 0 because in parking lot test needs to suppose terrain dry and assign permeability very low for producing overland flow soon and also needs to define heavy rainfal for timestep of 1 hour followed by 1 hour dry for enough time for producing streams and then getting stream as output file to check it. I have no idea about how to do that and what type of files i need to prepare and also what type for output. Is there any Idea or guide for doing that? If so it will make my day and will highly be appreciated.

Best

[Chen Yang]

Hi Sadegh,

 

Based on my understanding, the initial pressure doesn’t matter since the permeability is very low anyway. So you just set a constant water table depth (>0) with the hydrostatic condition as the initial condition is fine. For other setups, the test cases in section 3.2 in Condon and Maxwell (2019, computers & geosciences) should be good examples.

 

Thanks,

Chen

 

-- 

Chen Yang, Ph.D.

Associate Research Scholar

Department of Civil and Environmental Engineering

Princeton University

--
You received this message because you are subscribed to the Google Groups "ParFlow" group.
To unsubscribe from this group and stop receiving emails from it, send an email to parflow+u...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/parflow/92ba550f-5ba1-4929-966f-15652c636896n%40googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

[Sadegh Dalfardi]

Hi Chen

Thank you so much for your answer. I think we dont need any pressure file i said that because i saw a test case for producing run off by slope files and pressure file over one time step and probably i made a mastake about it. you mean we need to take a constant water table near the surface to make the basin be prone to run off sooner? can we also set the hydroulic conductivity or permeability very low to see the figure of streams and run off to check them? or maybe combination of all? in parflow manual dont explain about parking lot test or making an example. i can give it effort to find the best ways for getting output but i am not sure about which commands get the streams and run off paths to check it? for example pfsurfacerunoff and need to compute top of domain based on pfcomputetop. I will read the mentioned article i hope can afford that.

Thank you Dear Chen

Best

[Reed M. Maxwell]

There’s info in the ParFlow short course on how to set up a parking lot test.

 

Typically this is done with a 2D domain (nz=1) that is thin, has very low K (as Chen pointed out), zero initial pressure and a short rainfall pulse and recession.  You can see an example script for the Little Washita here. The slides that describe this are here.

 

Hope this helps

 

Reed

 

Reed M. Maxwell, Ph.D.
Professor

Department of Civil and Environmental Engineering

High Meadows Environmental Institute

Director, Integrated GroundWater Modeling Center

Princeton University

maxwell.princeton.edu

igwmc.princeton.edu

To view this discussion on the web visit https://groups.google.com/d/msgid/parflow/965ccfe3-8e20-4012-a147-2f4ac46c03dbn%40googlegroups.com.

[Sadegh Dalfardi]

Hi Dear Reed

Thank you so much for your answer. Yes your sending files will be helper. I will try it and also think it's necessary to highly appreciate your guides and helps and of course highly appreciated of Dear kind Chen too.

Best