Regarding previous turning operation and checking of parameter in ANSYS 2020 R1 file


After your suggestions I am stating new discussion here,

Respected sir @peteroznewman

Thank you for your wonderful suggestion on 'PTC Mathcad Prime',

1)Sir actually we are trying to shift the tool 0.7mm towards the workpiece so that we don't have to give the depth of cut (that is the x -component ) , but we could not make it . So if possible can you shift the tool 0.7mm and send us back the file by making the changes . 

Sir these is my final file with appropriate boundary condition 

That is depth of cut =0.7 mm 

Feed = 0.4 mm per revolution 

Rpm = 350 

Workpiece dia = 23 mm 

End time = 1.364 as per your previous calculation 

Similarly cutting velocity = as per your calculation

Angular velocity = as per your calculation

Since we need to have 50 revolution which means 50*360 = 18000 ( please check that it is right ) 

NOTE: Please check my Remote displacement all data and also check global coordinate along with all the selection of faces which i have selected in below ansys 2020 R1.

So sir please take a look at my file and let me know if i have made any mistake soo that i can finally start with my simulation as soon as possible 

https://drive.google.com/file/d/1wCKeaeudjwGROy7uAYgOVcsqCFu_hjDQ/view?usp=drive_web

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Comments

  • MAMIN219MAMIN219 Member
    edited October 6

    @peteroznewman Thank You sir for your reply

    Sir, Have you opened my file which is ANSYS 2020 R1.

    Are there any mistake to choosing any data and selection of faces/ geometry and all of my calculations

    Please check my Remote displacement all data and also check global coordinate along with all the selection of faces which I have selected in my previous Discussion

    Please give your valuable feedback on my previous query so that I can put my simulation


    Thank you

    Mihir Amin

  • It is a mistake to select the whole workpiece body for the remote displacement, just use the back face.

    It is a mistake to select the whole tool body for the displacement, because that prevents deformation in the tool. Hold the tool on faces where it is supported by the machine that clamps on the tool. You will need to make some faces for that, or cut the tool off short and hold the back face of a shorter tool.

  • Thank you for your answer @peteroznewman Sir

    Now I am understand the logic behind the selection of faces.


    1) I have mentioned global coordinate for remote displacement and mention for 50 revolution and 18000 as z components. This all calculations are correct?

    2) Sir in your file you have selected coordinate system for cylinder and coordinate system 2 for Tool but you cant mention in displacement of remote displacement what is reason behind that please highlight more in that

    3)Sir @peteroznewman this your file and you have selected global coordinate for this .why you have not applied coordinate system 2 for tool is there any specific reason for that?

    According to your guidance i have selected back faces of workpiece

    In that above fig in have mentioned global coordinate for remote displacement is correct or any changes in this?

  • peteroznewmanpeteroznewman Member
    edited October 6

    For Displacements,, any cartesian coordinate system that points in the right direction can be used.

    For Remote Displacements, any cartesian coordinate system can be used. What is important is the coordinates in the remote displacement, because that is the point where the object rotates about.

    What is coordinate system 2 for? I don't need that.

    Please mark the other discussion with an Accepted Answer.

  • @peteroznewman Respected sir

    Actually I am little bit confused with your above calculations


    In this Feed rate =Feed ×RPM

    Where Feed =0.4mm/revolution and RPM=350 revolution per minute

    So according to this I am getting feed rate 2.33mm/sec

    And if i use the same formula and convert RPM to rad/sec that is 36.65 rad/sec then i get the same answer which you have shared that is 14.661mm/sec


    So sir what can i do

    Will i take RPM Or value of rad/sec . Please clarify my doubt.


    Thank you

    Mihir Amin

  • Respected sir,@peteroznewman

    Actually i am bit confuced with calculation which you share with @MAMIN219

    Feed rate = feed*rpm

    Feed = 0.4 mm per revolution

    Rpm = 350rpm

    According above eqaution i get 2.33 mm/sec but here i use rpm =5.833 revolution per sec.

    And i use same formula and convert rpm into rad/sec i get same ans which you share with @MAMIN219 14.661 mm/sec

    So sir i have to use rpm in the formula or rad/sec

    Pl

  • Respected sir @peteroznewman

    Actually i am bit confused with calculation which you shared with @MAMIN219

    where

    feed rate = feed *rpm, where feed = 0.4mm/revolution and rpm =350

    so according i am getting feed rate to be 2.33 mm/sec

    And if i use the same formula and convert rpm to rad/sec that is 36.63 rad/sec then i get the same ans which you shared that is 14.661 mm/sec

    so sir i have to use rpm in the formula or rad/sec

    pl

  • Have you gone through our pervious discussion ?

    @peteroznewman Sir has cleared my most of doubt with very great and effective manner which will be helpful for everyone. I am thankful for providing clear concept here

    Unfortunately @Kp_9079 @Nachiket_0301


    We all are facing the same doubt

    Dont worry our doubts will get cleared 😊 by @peteroznewman

  • @peteroznewman please Solve our query as soon possible so that we will further simulate for better understand and enhance our skills

    Thank you sir

    Mihir Amin

  • peteroznewmanpeteroznewman Member
    edited October 11

    @Kp_9079 @Nachiket_0301 @MAMIN219

    RPM is the name of a variable. In hindsight, a better name would be AV for angular velocity, to avoid the confusion between the variable name and the unit name.

    Angular velocity can be measured in rad/sec or revolutions per minute (rpm) or revolutions per second. The value of RPM is 350 rpm or 36.63 rad/sec.

    I created a new variable called RPS for revolutions per second.

    See if the following correctly calculates the values you need.

  • Thank you @peteroznewman sir

    actually i am also doing the same analysis

    But when i started the simulation for tool travel for 2mm then it was showing 3000 hours for the simulation to complete

    and after 1hour energy error occured

    So is there any other method that can reduce the simulation time to approximately 3-4 days and still i get the accurate real result .

    how can i apply mass scaling or time scaling in these simulation ?

  • Use the Mesh Metric of Characteristic Length (CL). Locate the element with the minimum CL. That element is controlling the maximum time step, which controls the elapsed time for the simulation. If it is the case where that element is not one being cut by the tool, revise the mesh to make the minimum CL element much closer to the elements being cut. Double the minimum CL and you can expect to cut the elapsed time in half.

    If you increase the density of the element by a factor of four, you can expect to cut the elapsed time in half.

    These two factors and the Young's Modulus combine in an equation to compute the maximum time step. Mass scaling is an artificial (numerical) mechanism for increasing the CFL (Courant-Friedrichs-Levy) timestep of individual elements that govern the maximum allowed timestep of explicit transient dynamic solutions in Autodyn. Increasing the timestep has the obvious benefit of reducing the number of cycles required to run a simulation to a given point in time. Educated use of this option can therefore result in significant improvements in efficiency.

    Read the ANSYS help page on Mass Scaling.

    To open the link above, follow these directions.

  • Thank you so much sir @peteroznewman

    However, I am a beginner

    So how Can i locate Element with Minimum Mesh metric characteristic length ?

    it will be true if i Double the value of mesh metric CL , even though it is located where it is cut by the tool ?

  • This video will teach you how to use the Mesh Metrics tool. The Characteristic Length metric is at the bottom of the list and is not shown in this video.

  • @MAMIN219 Please choose a reply to mark as the Accepted Answer and open a New Discussion for any new questions.


  • @peteroznewman Yes accepted answer sir.

    Thanks for always answer me for my simulation.

    I have some doubt so now i will start new conversation

  • @MAMIN219

    You need to click a link below one of my replies to set this discussion as solved. It used to be called "Is Solution". You can see some other posts have an "Accepted Answer"

    You have not done that yet.

  • Yes Sir @peteroznewman

    I have calculated the parameters for 2mm tool travel. In my simulation I have changed mesh and exported from hypermesh. According to our last discussion we have calculated all the things and gave all the parameters according to your guidance, our workpiece is rotating but still the tool didn't travel. Here I'm attaching a 19.2 file, please check it as soon as possible.


  • @MAMIN219 The tool did travel 2 mm.

    The problem is the tool is 6,802.3 mm wide so moving 2 mm is not easy to see. You can measure the distance between vertices and the measurement shows up on the bottom of the window.

    Please mark an answer as accepted and open a New Discussion to ask new questions. This discussion has become too long.

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