API EDEM

Kiran Purushothama Keshavan
Kiran Purushothama Keshavan Altair Community Member
edited April 5 in Community Q&A

Hi,

I ran this simulation, I see that the EDEM text file in the folder by name field_query_prefs has density and viscosity data. 
When I run the simulation for density of 1.225 from 1000 which is the default,the particles seem to have not been effected by the field.cgns.

When I change the density back to 1000, the simulation works fine, why does this happen?

Tagged:

Answers

  • jerrinjobs
    jerrinjobs
    Altair Employee
    edited April 4

    Hi Kiran

    After changing the preferences file, depending on where the preference file is read within the code, you may want to reload the API model after every change. The API will then register the new preference file information and run the custom model.

    Hope this helps.

    Thanks,
    Jerrin Job

  • Kiran Purushothama Keshavan
    Kiran Purushothama Keshavan Altair Community Member
    edited April 4

    Hi,

    Thanks for your reply, is the units of denisty kg/m^3? 
    1. What is the typeof viscosity we're using fromthe preference files? What are its units? Is it the same as the one shown in Options from EDEM?

    2. I do not understand how my field's orientation is in such an orientation (see picture for reference)
    Is there a way to reorient this or does it say my setup's orientation needs to be changed to suit the field'smorientation to see some meaningful results.

    Thanks,
    Kiran

  • jerrinjobs
    jerrinjobs
    Altair Employee
    edited April 4
    Kiran Purushothama Keshavan said:

    Hi,

    Thanks for your reply, is the units of denisty kg/m^3? 
    1. What is the typeof viscosity we're using fromthe preference files? What are its units? Is it the same as the one shown in Options from EDEM?

    2. I do not understand how my field's orientation is in such an orientation (see picture for reference)
    Is there a way to reorient this or does it say my setup's orientation needs to be changed to suit the field'smorientation to see some meaningful results.

    Thanks,
    Kiran

    Hi Kiran

    1. The units depend on how the API is written. 

    2. The field cannot be oriented within EDEM. You can orient your equipments according to the field if you'd like, or maybe change the orientation in the CFD tool where you generated the field, and generate a new field with correct orientation.

    Hope this helps.

    Thanks,
    Jerrin Job

  • Kiran Purushothama Keshavan
    Kiran Purushothama Keshavan Altair Community Member
    edited April 4

    Thanks for your reply, 
    I have just modified my API case file of the example 'Field Data Coupling'
    I have not changed the units, I've just changed the fluid density of 1000 (I'm assuming the units are in kg/m^3) to density of air 1.225 kg/m^3.

    When I change the density of fluid from 1000 to that of air, then the particle fluid interation is very minimal (I do not see the particles being carried away by the wind), but the steady state velocity field from Ansys CGNS is at 50m/s, physically for a domain length of 7 meters I should be able to see some changes in the particle position. Please comment if I can make changes which could help get results where the particle gets carried by the wind velocity.

    Thanks,
    Kiran

  • jerrinjobs
    jerrinjobs
    Altair Employee
    edited April 4
    Kiran Purushothama Keshavan said:

    Thanks for your reply, 
    I have just modified my API case file of the example 'Field Data Coupling'
    I have not changed the units, I've just changed the fluid density of 1000 (I'm assuming the units are in kg/m^3) to density of air 1.225 kg/m^3.

    When I change the density of fluid from 1000 to that of air, then the particle fluid interation is very minimal (I do not see the particles being carried away by the wind), but the steady state velocity field from Ansys CGNS is at 50m/s, physically for a domain length of 7 meters I should be able to see some changes in the particle position. Please comment if I can make changes which could help get results where the particle gets carried by the wind velocity.

    Thanks,
    Kiran

    Hi Kiran

    I am not sure how you have written your API. Please check if the equations are correct. I would also do a hand-calculation to see if the force that EDEM calculates equal the analytical value of the force. If they are, then EDEM is calculating the forces correctly, and indeed you will not see any movement. But if they are not equal, then you should check where in the code the equation is incorrect.

    Hope this helps.

    Thanks,
    Jerrin Job

  • Kiran Purushothama Keshavan
    Kiran Purushothama Keshavan Altair Community Member
    edited April 5

    I have done exactly as instructed in the tutorial but I just changed the density of the particle, the change in the simulation result is huge.

    Can you please help me with how I can get values for 'relativeVelocity.length()' ?

    Is there a manual that I can refer to understand the terms used in the API?

    What is particleVelocity? From the API code of the tutorial

     

  • jerrinjobs
    jerrinjobs
    Altair Employee
    edited April 5
    Kiran Purushothama Keshavan said:

    I have done exactly as instructed in the tutorial but I just changed the density of the particle, the change in the simulation result is huge.

    Can you please help me with how I can get values for 'relativeVelocity.length()' ?

    Is there a manual that I can refer to understand the terms used in the API?

    What is particleVelocity? From the API code of the tutorial

     

    Hi Kiran

    You can find the EDEM API Help at the following location:

    <EDEM_INSTALLATION_FOLDER>/src/Api/Help/index.html.

    The Help assumes that you have a basic understanding of C++.

    Hope this helps.

    Thanks,
    Jerrin Job

Categories