(精)Workbench12.0力学非线性_procedure.pptVIP

To answer this question, first consider, What is different about building a nonlinear model? Problem dependencies affect how a nonlinear model will differ from a linear one: In some cases, there will be no difference! In other cases, you must include special nonlinear features: Such as material test data (plastic stress vs strain). And special elements (such as contact elements). Later Chapters will provide case-by-case details of modeling tips for different nonlinear situations. Simulation meshes in ANSYS: The “Shape Checking” toggle is SHPP,LSTET,ON Use of Jacobian tests at integration points is the “Standard” or SHPP,LSTET,ON method, suitable for linear analyses Use of Jacobian tests at corner nodes is the “Aggressive” or SHPP,LSTET,OFF method. This is generally a more conservative approach and may be preferred for nonlinear analyses. This is because elements which undergo distortion during solution should have a good quality shape to begin with. Because Simulation uses its own criteria for shape tests, SHPP,OFF is set when exporting a mesh to ANSYS. Also, even if SHPP,ON is set, the criteria used for warning/error elements differs between Simulation and ANSYS ANSYS Details: In Simulation, the following elements are used: Solid bodies are meshed with 10-node tetrahedral or 20-node hexahedral elements SOLID187 and SOLID186 SOLID186 has KEYOPT(3)=2 by default in Simulation. If “Brick Integration Scheme” under the part Details view is changed from “Full” to “Reduced,” then KEYOPT(3)=0 is used. The latter is the default option in ANSYS, and is useful to alleviate volumetric locking. Surface bodies are meshed with 4-node quad shell elements SHELL181 using real constants Section definition (and offsets) are not used Line bodies are meshed with 2-node beam elements BEAM188 (with 3rd orientation node) Section definition and offsets are supported ANSYS Details: In Simulation, the following elements are used: Solid bodies are meshed with 10-node tetrahedral or 20-n