Hi i am running a thermomechanical model the model is large and highly nonlinear with contact. S is the socalled structural damping matrix the structural damping matrix. Advanced linear dynamics and substructuring capabilities in abaqus. Choose use solver default to allow abaqus standard to decide whether a symmetric or unsymmetric matrix storage and solution scheme is needed. Abaqus standard will use the unsymmetric matrix storage and solution scheme automatically. When i run an abaqus job in server, i got the following error. By continuing to use pastebin, you agree to our use of cookies as described in the cookies policy. This choice of the unsymmetric matrix storage and solution scheme will consider changes to the friction model. Abaqusstandard provides the capability to input stiffness, mass, viscous. This choice of the unsymmetric matrix storage and solution scheme will be made based solely on the model definition. Moreover, during contact, it may be a asymmetric matrix solver due to contact non. Just recently, i have encountered a rather unexpected result. The simulation terminates prematurely if i force abaqus to use unsymmetric solver sometimes better for contact problems with unparallel contact surfaces. Choose unsymmetric to restrict abaqus standard to the unsymmetric storage and solution scheme.
Abaqus2matlab is a novel software to connect abaqus with matlab, run abaqus with matlab, transfer results from abaqus to matlab. When i run an abaqus job in server, i got the following. In step use the unsymmetric equation solver matrix storage unsymmyes, when the model has 3d curved master surfaces, gives better convergence. In largedisplacement analyses in abaqusstandard some distributed load types introduce unsymmetric load stiffness matrix terms. Thus, if you modify the friction definition during the analysis to introduce a friction coefficient greater than 0. However, it runs just fine without convergence problems if i use sym. We use cookies for various purposes including analytics.
Displacement increment for contact is too big what does this mean. We use your linkedin profile and activity data to personalize ads and to show you more relevant ads. Abaqusstandard will automatically choose whether a symmetric or unsymmetric matrix storage and solution scheme should be used based on the model and. Hello, i would like to know under what situation will a stiffness matrix in a fem problem become nonsymmetric.
This parameter can be used only if the userdefined element type is linear and its stiffness andor mass matrices are to be read from the abaqus standard results file of a previous analysis in which they were written by using the element matrix output or substructure matrix output options. Asymmetric axisymmetric caxa, saxa elements are now supported in the cae. Unsymmetric matrix input treatment in abaqus 2018 advanced mechanical features such as contact friction models can introduce unsymmetry. Abaqus standard will use the unsymmetric matrix storage and. Apart from symmetry bc, i saw that in the step of abaqus, there is a tab call equation solver, and in this tab we can choose to use symmetric equation solver and unsymmetric equation solver.