Count particles that leaves through an outlet

sma079 · April 4, 2011, 04:48

Hi,

There is maybe a very simple solution to my problem but I am new at this and need some input to move on.

I am working on a cyclone separator case and want to obtain a grade efficiency curve by injecting mono sized particles and then count the particles that leaves the two outlets respectively. I only need to count one of them to obtain the balance.

Im using LES Lagrangian. I read in a post on this forum that I need to use boundary sampling to obtain this. I have chosen that model, but I don´t know how to post process it.

I dont find anything useful about it in the manual either.

I need this for my Master Thesis as I want to compare the results from experiments with simulations.

Please help me out here=)

Best

Svein

sma079 · April 4, 2011, 06:02

Can also mention that I use version 5.06.010

sma079 · April 4, 2011, 15:01

Anyone?

Im using a presentation grid to inject about 500 particles at a specific time, and after that no more particles are injected. I just want to know if there is an option to know how many of the injected particles that leaves through one of my outlets.

Best

Svein

Mazine · September 19, 2011, 10:14

Hi Svein,

I am working on sampling issues right now as well. I try to calculate the loss of particles (radioactive aerosols) during transportation in a air flow. I am injecting mono sized particles and then count the particles which get stuck to the wall.

I'm using Lagrangian Multiphase Model and want to use the boundary sampling to obtain the particle count, but I don´t know how to post process it.

I need this for my Bachelor Thesis as I want to compare the results from experiments with simulations. Can you provide me some information about how you did it during your thesis?

Best regards,

Matìas

RobertB · September 20, 2011, 07:43

I suggest you ask CD for the file format and/or a basic program that reads the files. Then you can do whatever you want with the data.

We do something similar with STAR and it allows you to get whatever properties/ data you want most easily.

siara817 · July 24, 2012, 08:55

I know it is so late to answer to this, but, it may work for others: you need to activate Track File model,which is located under the models of lagrangian phase. You need to do that before starting solution. After finishing solution, add the track file which is generated by going to Tools/TrackFiles. Then use the proper field function located in the Tools/Field functions/Track.

MartiJ · July 25, 2012, 05:30

I did something similar when counting exiting steam bubbles from another liquid. If I remember correctly, you can use "escape" condition for your Lagrangian particles at the outlet boundary and then create a report to read the flow or amount of solid particles hitting your outlet plane.

BR

kannstmasehn · May 24, 2013, 01:54

What are the settings for that report? I created a sum report and chose all parts. But what kind of scalar function do I need to report how much of the flow rate hits a wall?

govendad · July 21, 2015, 11:12

Hi All,

I am running a Euler/Lagrangian sim. I am using a part injector to inject 5.5kg/s of particles. I have the following questions:

How do I determine how many particles are being injected and how many are leaving at the outlet. I also have recirculation occurring so not all the particles injected will leave.

I have tried boundary sampling but this does not seem to work, maybe I am using it wrong.

Any advice will be appreciated.

Thank you.

govendad · July 21, 2015, 11:13

Quote:

Originally Posted by govendad

Hi All,

I am running a Euler/Lagrangian sim. I am using a part injector to inject 5.5kg/s of particles. I have the following questions:

How do I determine how many particles are being injected and how many are leaving at the outlet. I also have recirculation occurring so not all the particles injected will leave.

I have tried boundary sampling but this does not seem to work, maybe I am using it wrong.

Any advice will be appreciated.

Thank you.

Good day, Please advise on the request above.

Eike · July 29, 2015, 06:29

Counting particles is pretty easy using reporting and monitoring. I have a sim with one inlet and 6 outlets ...

I don't use a track file but of course you have to activate it @ Continua -> Physics -> Lagragian Multiphase -> Phase -> Models to get the particle tracks. You can deactivate it later if you don't like getting the track files @ your HDD.

To count particles @ whole system just setup an "Element Count" report. You can do it for all particles or for each phase. Parts = Lagrangian Phase(s)

To count particles @ outlets or inlets first setup an "Element Count" Report with Parts = Particle Tracks -> phase X @ boundary X

Now you put "Sum of Report: Element Count XYZ" into a "Maximum" Report. Plot this and you will get number of particles at the Y-axis and time at the X-axis. Can be exported as csv-file ...

Deranda · November 3, 2015, 08:32

Hi Community,

im working on a cyclone separator as well.

an i wann count the particles.

Quote:

To count particles @ whole system just setup an "Element Count" report. You can do it for all particles or for each phase. Parts = Lagrangian Phase(s)

To count particles @ outlets or inlets first setup an "Element Count" Report with Parts = Particle Tracks -> phase X @ boundary X

Now you put "Sum of Report: Element Count XYZ" into a "Maximum" Report.

It works in 9 out of 12 cases. Only god himself knows why it dont work in those 3 cases.
(these 12 cases originate from different particle sizes at the inlet, outlet and sump)

i monitor the element count as well and all element count reports are doing fine.
My problem has to refer to the field sum monitor, but i dont have any idea whats going wrong.

does anyone has an idea?

thanks for your help,
Nils

jeroendemto · September 27, 2018, 07:16

Quote:

Originally Posted by Eike

Counting particles is pretty easy using reporting and monitoring. I have a sim with one inlet and 6 outlets ...

I don't use a track file but of course you have to activate it @ Continua -> Physics -> Lagragian Multiphase -> Phase -> Models to get the particle tracks. You can deactivate it later if you don't like getting the track files @ your HDD.

To count particles @ whole system just setup an "Element Count" report. You can do it for all particles or for each phase. Parts = Lagrangian Phase(s)

To count particles @ outlets or inlets first setup an "Element Count" Report with Parts = Particle Tracks -> phase X @ boundary X

Now you put "Sum of Report: Element Count XYZ" into a "Maximum" Report. Plot this and you will get number of particles at the Y-axis and time at the X-axis. Can be exported as csv-file ...

Hey Eike,

thanks for your help, I just have a small question, what do you mean with Parts = Particle Tracks -> Phase X @ boundary X? If I choose parts I can go to the particle tracks and select the phase but not combined with a boundary. What am I missing?

Regards,
Jeroen

Deranda · September 27, 2018, 09:19

You have to activate Boundary Sampling, so the Software knows, that the chosen lagrangian phase should be tracked at a chosen boundary.

You can find this option under:
Physics - Lagrangian Multiphase - Lagrangian Phases - "MyLagrangianPhase" - Models - right click and choose Boundary Sampling

a new node appears where you can find the following settings:

1) Boundaries: The set of boundaries for which particle sampling is active.

2) Scalars: Selects a set of scalar field functions, with a Select Objects dialog, for recording on the boundary.

3) Selects a set of vector field functions, with a Select Objects dialog, for
recording on the boundary.

jeroendemto · September 27, 2018, 09:56

Thank you Deranda, the counting works now!

However, it gives the amount of particles per timestep. Do you know how I can set it up in such a way it will sum over all timesteps?

regards,
Jeroen

Deranda · September 27, 2018, 10:07

dont know, if it is still the same proceedure, but when I worked with particle tracks, I use field sum monitors.

From UserGuide:
"The Field Sum is the total of a field function value as the solution progresses, computed for each cell or boundary face in the selected parts."

From Steve Portal:
"To calculate the cumulative mass of particles having passed an interface, several post processing objects are required:
-A report to integrate mass flux over the interface of interest, giving a mass flow rate (mass/time)
-A field function to multiply this mass flow rate by the current time-step size (mass/time step)
-A Field Sum monitor to add up the mass over a specified time internal (mass)
Another report to access the field sum"

Deranda · September 27, 2018, 10:15

If I remember correctly, you have to choose the fieldfunction from the
fieldfunction -> tracks subtree (the field functions is named something like :"Track:Particle Diameter"
and the boundary for the field sum monitor should be Tracks:
Phase 1 @ Body: Boundary

jeroendemto · September 28, 2018, 04:17

The method to sum the particles is as follows:

-after making the element count for the particles make a field sum monitor with field function report: element count and parts: region -> outlet.

-make a maximum report with field function: Sum of Report: Element count and parts Region outlet

-then you can create a plot by right clicking the maximum report and click "Create monitor and plot from file"

April 4, 2011, 04:48	Count particles that leaves through an outlet	#1
sma079 New Member Svein-Arne Marthinussen Join Date: Apr 2011 Posts: 3 Rep Power: 15	Hi, There is maybe a very simple solution to my problem but I am new at this and need some input to move on. I am working on a cyclone separator case and want to obtain a grade efficiency curve by injecting mono sized particles and then count the particles that leaves the two outlets respectively. I only need to count one of them to obtain the balance. Im using LES Lagrangian. I read in a post on this forum that I need to use boundary sampling to obtain this. I have chosen that model, but I don´t know how to post process it. I dont find anything useful about it in the manual either. I need this for my Master Thesis as I want to compare the results from experiments with simulations. Please help me out here=) Best Svein yesaswi92 likes this.

July 25, 2012, 05:30		#7
MartiJ New Member Marti J Join Date: Jul 2010 Location: swe Posts: 14 Rep Power: 15	I did something similar when counting exiting steam bubbles from another liquid. If I remember correctly, you can use "escape" condition for your Lagrangian particles at the outlet boundary and then create a report to read the flow or amount of solid particles hitting your outlet plane. BR siara817 likes this.

July 21, 2015, 11:12	Particle Mass balance	#9
govendad New Member GERD Join Date: Jul 2015 Posts: 2 Rep Power: 0	Hi All, I am running a Euler/Lagrangian sim. I am using a part injector to inject 5.5kg/s of particles. I have the following questions: How do I determine how many particles are being injected and how many are leaving at the outlet. I also have recirculation occurring so not all the particles injected will leave. I have tried boundary sampling but this does not seem to work, maybe I am using it wrong. Any advice will be appreciated. Thank you.

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April 4, 2011, 06:02		#2
sma079 New Member Svein-Arne Marthinussen Join Date: Apr 2011 Posts: 3 Rep Power: 15	Can also mention that I use version 5.06.010

April 4, 2011, 15:01		#3
sma079 New Member Svein-Arne Marthinussen Join Date: Apr 2011 Posts: 3 Rep Power: 15	Anyone? Im using a presentation grid to inject about 500 particles at a specific time, and after that no more particles are injected. I just want to know if there is an option to know how many of the injected particles that leaves through one of my outlets. Best Svein

September 19, 2011, 10:14		#4
Mazine New Member Matìas G. Join Date: Sep 2011 Location: Switzerland Posts: 1 Rep Power: 0	Hi Svein, I am working on sampling issues right now as well. I try to calculate the loss of particles (radioactive aerosols) during transportation in a air flow. I am injecting mono sized particles and then count the particles which get stuck to the wall. I'm using Lagrangian Multiphase Model and want to use the boundary sampling to obtain the particle count, but I don´t know how to post process it. I need this for my Bachelor Thesis as I want to compare the results from experiments with simulations. Can you provide me some information about how you did it during your thesis? Best regards, Matìas

September 20, 2011, 07:43		#5
RobertB Senior Member Robert Join Date: Jun 2010 Posts: 117 Rep Power: 16	I suggest you ask CD for the file format and/or a basic program that reads the files. Then you can do whatever you want with the data. We do something similar with STAR and it allows you to get whatever properties/ data you want most easily.

July 24, 2012, 08:55		#6
siara817 Senior Member siamak rahimi ardkapan Join Date: Jul 2010 Location: Copenhagen, Denmark Posts: 220 Rep Power: 17	I know it is so late to answer to this, but, it may work for others: you need to activate Track File model,which is located under the models of lagrangian phase. You need to do that before starting solution. After finishing solution, add the track file which is generated by going to Tools/TrackFiles. Then use the proper field function located in the Tools/Field functions/Track.

May 24, 2013, 01:54		#8
kannstmasehn New Member Tobi Join Date: Mar 2013 Posts: 26 Rep Power: 13	What are the settings for that report? I created a sum report and chose all parts. But what kind of scalar function do I need to report how much of the flow rate hits a wall?

July 29, 2015, 06:29		#11
Eike Member Eike Join Date: Sep 2011 Posts: 40 Rep Power: 14	Counting particles is pretty easy using reporting and monitoring. I have a sim with one inlet and 6 outlets ... I don't use a track file but of course you have to activate it @ Continua -> Physics -> Lagragian Multiphase -> Phase -> Models to get the particle tracks. You can deactivate it later if you don't like getting the track files @ your HDD. To count particles @ whole system just setup an "Element Count" report. You can do it for all particles or for each phase. Parts = Lagrangian Phase(s) To count particles @ outlets or inlets first setup an "Element Count" Report with Parts = Particle Tracks -> phase X @ boundary X Now you put "Sum of Report: Element Count XYZ" into a "Maximum" Report. Plot this and you will get number of particles at the Y-axis and time at the X-axis. Can be exported as csv-file ...

September 27, 2018, 09:19		#14
Deranda Member Nils Join Date: Nov 2015 Posts: 59 Rep Power: 10	You have to activate Boundary Sampling, so the Software knows, that the chosen lagrangian phase should be tracked at a chosen boundary. You can find this option under: Physics - Lagrangian Multiphase - Lagrangian Phases - "MyLagrangianPhase" - Models - right click and choose Boundary Sampling a new node appears where you can find the following settings: 1) Boundaries: The set of boundaries for which particle sampling is active. 2) Scalars: Selects a set of scalar field functions, with a Select Objects dialog, for recording on the boundary. 3) Selects a set of vector field functions, with a Select Objects dialog, for recording on the boundary.

September 27, 2018, 09:56		#15
jeroendemto New Member Join Date: Sep 2018 Posts: 25 Rep Power: 7	Thank you Deranda, the counting works now! However, it gives the amount of particles per timestep. Do you know how I can set it up in such a way it will sum over all timesteps? regards, Jeroen

September 27, 2018, 10:07		#16
Deranda Member Nils Join Date: Nov 2015 Posts: 59 Rep Power: 10	dont know, if it is still the same proceedure, but when I worked with particle tracks, I use field sum monitors. From UserGuide: "The Field Sum is the total of a field function value as the solution progresses, computed for each cell or boundary face in the selected parts." From Steve Portal: "To calculate the cumulative mass of particles having passed an interface, several post processing objects are required: -A report to integrate mass flux over the interface of interest, giving a mass flow rate (mass/time) -A field function to multiply this mass flow rate by the current time-step size (mass/time step) -A Field Sum monitor to add up the mass over a specified time internal (mass) Another report to access the field sum"

September 27, 2018, 10:15		#17
Deranda Member Nils Join Date: Nov 2015 Posts: 59 Rep Power: 10	If I remember correctly, you have to choose the fieldfunction from the fieldfunction -> tracks subtree (the field functions is named something like :"Track:Particle Diameter" and the boundary for the field sum monitor should be Tracks: Phase 1 @ Body: Boundary

September 28, 2018, 04:17		#18
jeroendemto New Member Join Date: Sep 2018 Posts: 25 Rep Power: 7	The method to sum the particles is as follows: -after making the element count for the particles make a field sum monitor with field function report: element count and parts: region -> outlet. -make a maximum report with field function: Sum of Report: Element count and parts Region outlet -then you can create a plot by right clicking the maximum report and click "Create monitor and plot from file"