dsearch definition in /INTER/TYPE2 tied interface

Andrea_20669
Andrea_20669 Altair Community Member
edited May 2022 in Community Q&A

Good Morning,

I am modeling an interface between SPH and solid hexa elements face segments. There are two region of the same component that I want to model with these two different meshes. In my case, since Ignore ≠ 1000, dsearch should be used but it is not clear to me how I should compute it.

When I define the interface /INTER/TYPE2. I am using:

-Ignore=1

-Spotflag=4

-Level=0

-Isearch=0

-Idel2=1

-dsearch=?

Thanks in advance for your suggestions!

Best Answer

  • Prasad Reddi_20512
    Prasad Reddi_20512 Altair Community Member
    edited May 2022 Answer ✓

    Hi Andrew,

    Is the distance between those 2 parts is varying while the simulation is going on? If not, you can measure the distance manually while modelling only and can use that value + tolerance in dsearch. Once you define the TYPE2 contact, you can check the TIE status in Hypermesh.

    Go to Tools -> Model Checker -> RadiossBlock. Then you will land in ModelChecker browser. You can run the modelchecker by clicking on the Green Circle with a tick mark inside (similar or same one as show in the picture)

    Once the run check is completed, then you can see one observation related to "Un-Tied nodes in interface type2", under this, you can see the TIE contact that you defined. Now, select that TIE contact and right click. You can see a button "Review", once you check this, you can now see any nodes which are TIED (in GREEN color) and UNTIED (in RED color). 

    Looking at this observation, you can now vary the value in dsearch option and follow the above process to see TIED & UNTIED nodes.

    Hope this will be useful.

    image

    Cheers,

    Prasad.

Answers

  • Prasad Reddi_20512
    Prasad Reddi_20512 Altair Community Member
    edited May 2022 Answer ✓

    Hi Andrew,

    Is the distance between those 2 parts is varying while the simulation is going on? If not, you can measure the distance manually while modelling only and can use that value + tolerance in dsearch. Once you define the TYPE2 contact, you can check the TIE status in Hypermesh.

    Go to Tools -> Model Checker -> RadiossBlock. Then you will land in ModelChecker browser. You can run the modelchecker by clicking on the Green Circle with a tick mark inside (similar or same one as show in the picture)

    Once the run check is completed, then you can see one observation related to "Un-Tied nodes in interface type2", under this, you can see the TIE contact that you defined. Now, select that TIE contact and right click. You can see a button "Review", once you check this, you can now see any nodes which are TIED (in GREEN color) and UNTIED (in RED color). 

    Looking at this observation, you can now vary the value in dsearch option and follow the above process to see TIED & UNTIED nodes.

    Hope this will be useful.

    image

    Cheers,

    Prasad.

  • Andrea_20669
    Andrea_20669 Altair Community Member
    edited May 2022

    Hi Andrew,

    Is the distance between those 2 parts is varying while the simulation is going on? If not, you can measure the distance manually while modelling only and can use that value + tolerance in dsearch. Once you define the TYPE2 contact, you can check the TIE status in Hypermesh.

    Go to Tools -> Model Checker -> RadiossBlock. Then you will land in ModelChecker browser. You can run the modelchecker by clicking on the Green Circle with a tick mark inside (similar or same one as show in the picture)

    Once the run check is completed, then you can see one observation related to "Un-Tied nodes in interface type2", under this, you can see the TIE contact that you defined. Now, select that TIE contact and right click. You can see a button "Review", once you check this, you can now see any nodes which are TIED (in GREEN color) and UNTIED (in RED color). 

    Looking at this observation, you can now vary the value in dsearch option and follow the above process to see TIED & UNTIED nodes.

    Hope this will be useful.

    image

    Cheers,

    Prasad.

    Thank you Prasad for your answer. I can see the nodes that are tied, how do I know if these have to be reduced in number or incremented?

  • Prasad Reddi_20512
    Prasad Reddi_20512 Altair Community Member
    edited May 2022

    Thank you Prasad for your answer. I can see the nodes that are tied, how do I know if these have to be reduced in number or incremented?

    It all depends on the area of tie that you would like to have. As per the below picture, you can choose dsearch = x,y,z depending upon the level of TIE that you would like to have between Part1 & Part2. Hence, you need to look for your requirement and choose a value for dsearch. Remember that once TIE CONSTRAINTS are established, it will be retained that status till the end of the simulation or any breakage of the parts happen, whichever is earlier. Hope this explanation helps.

    image

  • Andrea_20669
    Andrea_20669 Altair Community Member
    edited May 2022

    It all depends on the area of tie that you would like to have. As per the below picture, you can choose dsearch = x,y,z depending upon the level of TIE that you would like to have between Part1 & Part2. Hence, you need to look for your requirement and choose a value for dsearch. Remember that once TIE CONSTRAINTS are established, it will be retained that status till the end of the simulation or any breakage of the parts happen, whichever is earlier. Hope this explanation helps.

    image

    Ok, thank you again. I than think that if a breakage is not expected in this interface it is better to use as few nodes as possible in the secondary nodes group, hence dsearch is as small as possible? For instance, by looking at your drawing I would choose x. Is this reasoning correct?

  • Prasad Reddi_20512
    Prasad Reddi_20512 Altair Community Member
    edited May 2022

    Ok, thank you again. I than think that if a breakage is not expected in this interface it is better to use as few nodes as possible in the secondary nodes group, hence dsearch is as small as possible? For instance, by looking at your drawing I would choose x. Is this reasoning correct?

    You are welcome!

    Initially, it is required to calculate and fix the surface area (like x or y or z from the above picture) to TIE and use the value at which dsearch (distance between Part1 (Master)  & Part2 (Slave) surface area) falls accordingly.

  • Andrea_20669
    Andrea_20669 Altair Community Member
    edited May 2022

    You are welcome!

    Initially, it is required to calculate and fix the surface area (like x or y or z from the above picture) to TIE and use the value at which dsearch (distance between Part1 (Master)  & Part2 (Slave) surface area) falls accordingly.

    Thank you, Prasad!