Elements tested
- DSAX1
- DSAX2
- DS3
- DS4
- DS6
- DS8
- DCAX8
- DC3D20
- SAX1
- SAX2
- SAX2T
- STRI65
- S4R5
- S8R5
- S4RT
- S8RT
- CAX3T
- CAX4RT
- CAX4RHT
- CAX8R
- CAX8RT
- CGAX4RT
- CGAX8RT
- CGAX4RHT
- C3D4T
- C3D6T
- C3D8T
- C3D8RT
- C3D20R
- C3D20RT
ProductsAbaqus/StandardAbaqus/Explicit Elements tested
Problem description
Steady-state conditions are assumed in the Abaqus/Standard simulation. A transient simulation is performed in Abaqus/Explicit. The total simulation time is 0.4 seconds for the analyses using solid elements, and 0.06 seconds for the analysis using a shell element. This provides enough time for the transient solution to reach steady-state conditions in this problem. Mass scaling is used for the solid element analyses to reduce the computational cost of the Abaqus/Explicit analyses. Material:
Boundary conditions:For the thermal analyses the temperatures of the inside and outside surfaces are prescribed to be 200°C and 100°C, respectively. For the stress analyses the rotation vector in the circumferential direction is constrained, but the cylinder is free to expand axially. For the continuum element meshes equations are used to provide the rotational constraints. For the nonaxisymmetric cases symmetrical constraints are applied in the circumferential direction to model the complete cylinder. In the Abaqus/Explicit simulations the temperatures are applied gradually to ensure a quasi-static response. General:For all of the analyses except those using the coupled temperature-displacement elements (SAX2T, S8RT, CAX4RT, CAX4RHT, CGAX4RT, CGAX4RHT, CAX8RT, CGAX8RT, and C3D20RT in Abaqus/Standard and S4RT, CAX3T, CAX4RT, C3D4T, C3D6T, C3D8RT, and C3D8T in Abaqus/Explicit), the analyses are run in pairs: a thermal analysis followed by its corresponding stress analysis. Gauss integration is used for the shell cross-section for input file es54sxsj.inp. Reference solutionThe temperature distribution through the thickness of the cylinder is given by where is the outer radius, is the inner radius, is the outside temperature, and is the inside temperature. The analytical solution for the stresses is given in Chapter 15 of “Theory of Plates and Shells,” second edition, by Timoshenko and Woinowsky-Krieger. The stresses at the outer and inner surfaces are given by where E is Young's modulus, is the coefficient of thermal expansion, and is Poisson's ratio. The upper sign refers to the outer surface, indicating that a tensile stress will act on this surface if . This gives a theoretical stress of 171.43 MPa. Results and discussionThe axisymmetric and second-order shell elements agree exactly with the theory. The first-order three-dimensional shells (S4R5) show an error of −5.1%. The continuum elements show small discrepancies (< 1%) from the reference solution. The results obtained with Abaqus/Explicit are in close agreement with the analytical solution and with those obtained with Abaqus/Standard. Input filesAbaqus/Standard input files
Abaqus/Explicit input files
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