Learning Forum

[Neel Shah]

Hi there, 

I'm attempting to sample trajectories via the following window. Once I choose the "start" option, the window goes grey as if it is running, but nothing is shown in the console window while this is happening. 

 

As the screenshot above shows, I've let this run for over 2 hours with no progress or nothing shown in the console window. I'm unsure what I may be doing wrong; any help would be much appreciated. 

Many thanks,

Neel

[Rob]

If you click into the console window and press Enter a couple of times what happens? Have you run any iterations or otherwise triggered the particle tracks to update? 

[Neel Shah]

Hi Rob,

I've tried this in the console window, and there are no real updates. I can only see the following:

I'm currently running a DPM iteration. I've got particles visualised, but I'm unable to gain results from this sample trajectories window. There are no updates or anything that happens when I click start. 

 

[Rob]

OK, so we now know the solver is updating the tracks. Next question, are any of the tracks passing the inlet_uv surface?

[Saima Bukhat Khan]

I also have the same problem, I am reading the sample first from boundaries say outlet, than selecting the injection and click start and stop a file is saved, after that in histogram selecting sample as "outlet" my variable "diameter, weight as mass and histogram shows nothing. 

Attaching screen shot: Can you please the solution for this problem. 

[Rob]

Assuming the outlet is set as the only escape boundary, how many "escaped" fates are reported in the TUI?

[Saima Bukhat Khan]

The particles till last simulation were like this:

number tracked = 811911, escaped = 438, evaporated = 447, shed = 4

[Rob]

OK, that's a good start. If you open the .out file in a text editor what do you see? I'm not sure what the planes do if you also select a boundary, so if the file is empty, deselect the plane and try again. 

[Saima Bukhat Khan]

So I have tried by just selecting the outlet boundary, without selecting plane and start it and than stop, and than histogram and again it shows these line, without histogram. The file for the sample is written in .dpm format and than it shows this values in consule as well 

for diameter

total number = 1e-20

mean = 0

min = 1e+10

max = -1e+10

sum = 0

standard deviation = 0

 

[Rob]

That's the Summary. The file ought to look similar to a DPM injection file with information on what particle ID passed the surface at what speed and time. 

[Saima Bukhat Khan]

You are talking about this file than this is also empty:

[Rob]

Which means no particles passed through the surface. Have you done a particle update between turning on the report and checking the file? 

[Saima Bukhat Khan]

I don't understand the question, I am creating the smaple file for histogram by selecting the above shown in screenshot above and the file which is written is shown as well. Am i missing any step why no particles are written here when my particles are tracked, escaped as well from boundary. To calculate the sample I am pressing start option and than stop and than loading the file. Please let me know what's going wrong here?

[Rob]

Start, run a DPM update, or some iterations/timesteps and then stop. Otherwise if no particles cross the surface whilst it's recording the file will be empty. 

[Saima Bukhat Khan]

For how long the DPM update should be run? right now i m starting and stoping after few seconds. 

[Rob]

Long enough that particles from the injection are passing through the surface.