Jump to content
mpvnaresh

Displacements in a DTRAN Solution

Recommended Posts

Hi all 

 In a Direct Transient solution i have given a acceleration load with certain frequency and amplitude.

When  icheck displacements in the location where acceleration is applied, The Displacement curve is a not oscillationg one.Instead it is keep on going.

Can any one help me in getting the oscillating displacements.

I have tried by changing all options of FORM(1) in Displacement output request.but no use.

Please help me in this .

 

 

Displacement_Output.PNG

acceleration_Load.PNG

Share this post


Link to post
Share on other sites

Sir 

 

with displacements as input load it is oscillating .But the question remains same.

If i convert it into displacements obviously it oscilates as we are giving displacement directly.

But my load case is in acceleration i need to apply it in accelerations only.

 

Share this post


Link to post
Share on other sites

Could you please consider initial velocity for the base setup where you have time Vs accel.Transient initial conditions are defined using a TIC Bulk Data Entry. Initial displacements and initial velocities can be defined. This should help you to avoid drift in the displacement plot and get oscillating plot.

Share this post


Link to post
Share on other sites

Sir 

 

I am not able to give Input of Initial conditions . Can you please help in how to do this?

How to create TIC Bulk data entry. And also i have no data for initial displacements and initial velocities then how to get those values. 

Share this post


Link to post
Share on other sites

Sir

 

I really Appreciate this.

Thanks a lot for your time.

I think this is solved. 

But when try to integrate the acceleration curve to get celocity i am gettion a Zero velocity. Please help me in the methodology for getting velocity.and also how did you created TIC (V).

When i go go to load type page Velocity type is Blank.

 

Thanks again for the support sir.

Capture.JPG

Share this post


Link to post
Share on other sites

TIC V you can create from constraints panel & set the load type to TIC V.Sorry i cant provide you right now the hand calculation which we did to calculate Intial velocity,  as i am away from office desk.However,I do have the math we performed in HyperGraph to crosscheck.PFA mvw file for same,

TIC V.JPG

Ganesh Accel to Intial velocity.mvw

Share this post


Link to post
Share on other sites

Sir

 

I calculated Initial Velocity and applied as TIC(V).

But after the compltio of acceleration cycle displacements are cumulative.

(which mathematically  may true, As Acceleration=0,  Velocity which is integral of Acceleration = constant , Then Displacement is a straight line which is cumulative )

How can we make the  velocity, displacement to be zero after the load (Acceleration)is removed . 

Capture.JPG

Share this post


Link to post
Share on other sites

×
×
  • Create New...