'ElastoPlastic Analysis of an Oil Pipe' simulation project by hramesh_babu


#1

I created a new simulation project called 'ElastoPlastic Analysis of an Oil Pipe':

Pipes in Oil and Gas Industries are widely exposed to higher temperatures and pressures which might lead to blowouts. In order to prevent pipe breakage due to blowouts, closing and sealing of pipes is of high necessity. For this, the pipes are Simulated for Nonlinear case with larger deflections and contacts using two flat stiff indentors.


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#2

Nice Work


#3

Application:

A blowout is the uncontrolled release of oil or Natural gas from an Oil Rig, after pressure control systems have failed which leads in disaster. To prevent this, the pipe needs to be analyzed and Simulations should be carried out at different scenario.

Objective:
Pipes in Oil and Gas Industries are widely exposed to higher temperatures and pressure which might lead to blowouts. To prevent due to blowout, closing and sealing of pipes is of high necessity. For this, the pipes are simulated for Nonlinear Case with larger deflections and contacts using two flat stiff indenters.

CAD Model:

The 3D-CAD Model is modeled in Online Software Onshape. The following CAD figure is used for analyzing.

The dimensions of the Model are as follows:

  1. Indenters: Width = 200mm, Height = 227mm.
  2. Pipe: Outer Diameter = 200mm, Inner Diameter = 175mm.

Mesh:

The following figure shows Meshing view.

The Properties of Mesh are as follows:

  1. Mesh Type: Tet-Dominant
  2. Element Sizing: Coarse Mesh
  3. Element Order: First Order

Since the geometry has nonlinear contact behavior coarse mesh is used to reduce the computation time to obtain the results.

Boundary Conditions and Simulations:

The important part of the model is to choose the analysis type and choosing the boundary conditions for the respective CAD Model. Both the indenters have contact with pipe. The Indenters acts as a Master components and Pipe acts as a Slave components.

Results and Discussions:

The following figures are obtained from Simscale Software and pictures are generated through screenshots. The deformed shapes are also obtained using the filter “Warp by Vector”, which helps us to see the deformed image in the real scale.

From the above figure it clearly states that, there are larger displacements in the center of the pipe, this is because of contact with two indenters. The two indenters has physical contact with center of the pipe which results in maximum displacement when compare other cross section of the pipe.

The Von-Mises stress is the equivalent stress of the component (reference configuration), whereas the Cauchy Stress signifies the deformed stress (i.e.) stress obtained in the current configuration according to Continuum Mechanics. The following figures represents Von Mises and Cauchy Stress.

The below mentioned figures refers to the total nonlinear strain in deformed state. One can be able to see that the accumulation of Nonlinear strains in the middle of the pipe because of the physical contact.


#4

Nice simulations there @hramesh_babu! Kudos! :slight_smile:


#5

Thanks @jousefm


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#7

I wonder if this simulation can be used to get the stress strain curve validating the model with measuring the load and strain during flattening the pipe. I am not able to see the simulation result as a function of load. Is it possible to see the results and create a table of load versus displacement or stress versus strain?


#8

Yes, is it possible. Re-run the same simulation by adding result control (Area Calculation - Reaction Force - Sum) then you will be getting a plot with "Reaction Force versus time". If you're interested in "Force versus Displacement" graph, multiply the time data with 0.05 (d = 0.05*t in constraint 1).