It is an induced force that is represented in the equation of motion using the b matrix and velocity vector. How can i extract the mass and stiffness matrix from nastran via dmap including constrained nodes. Dmigout requests global matrix output to the model results output file. The mass matrix formulation is a userselectable option in nx nastran. Mass and damping are associated with the motion of a dynamic system. This solution sequence is available with nx nastran aeroelasticity. The id of the damping is automatically updated by autodesk nastran incad. The damping matrix for transient analysis is assembled from the. Terms are added to the global damping matrix before any constraints are applied. Applies structural based damping to transient analysis. Aerodynamic flutter analysis nastran sol 145 nastran sol 146. It represents the special case where we choose to form the damping.
The physical causes of damping in dynamic analysis are any processes which. Therefore, structural damping is included by means of equivalent viscous damping. B2gg bdmig option definition type name name of the matrix that is defined on the dmig bulk data entry. Msc nastran, patran tutorial modal frequency response. The viscous damping force is a damping force that is a function of a damping coefficient b and the velocity. This includes frequency response, direct matrix input, modal effective mass, complex eigenvalue analysis, dynamic optimization, and test analysis correlation. The mass matrix in nx nastran may contain much more information than simple.
By solving a set of smaller matrices mass, stiffness, damping, and loads instead of one very large matrix, you can reduce the disk space. Dampings inventor nastran 2019 autodesk knowledge network. Direct input matrices will not be used unless selected. Character damp include global damping matrix output. To solve this problem, im deleting the linescolumns attached to these nomass degrees of. For flutter, the sensitivity of the damping levels computed in a pkflutter analysis are available. I am trying to extract the mass and stiffness matrix from my nastran model using dmap. Autodesk nastran incad software brings advanced analysis techniques to the. Increased efficiency is the primary reason to use msc. In this class, you will be exposed to various aspects of dynamic analysis using msc nastran. There are different types of damping used by fea software, depending on the dynamic solver used. Extseoutstif, mass, dmigbdf extseoutmass, dmigop2 option definition type default stif include global stiffness matrix output. How can i extract the mass and stiffness matrix from nastran via.
Model requests model data translation to the bulk data output file. Implementing automated multilevel substructuring in nastran. The physical causes of damping in dynamic analysis are any processes. How nonlinear modal analysis is simulated using a software. To create a damping, rightclick on dampings in the model tree and select new to open the window below. Specifies the type, format, and media for superelement data storage. Nastran inherently solves large systems of equations efficiently using sparse matrix algorithms. The base of the plate is excited by a sinusoidal excitation.
Secondly, nastran solves the characteristic equations eq. Description type default model and matrix data output. How can i extract the mass and stiffness matrix from. This software and related documentation are proprietary to siemens product.
Description type default frequency of interest for structural damping. Dmigop2 requests global matrix export to a nastran output 2 formatted results file. Aerodynamic matrices are computed explicitly at each of the usersupplied mach number and reduced. Linear statics normal modes buckling connectors dynamics heat transfer adams integration unlimited model size direct matrix abstraction programming dmap. Nastran assigns mass only to the translation dofs, what makes the original mass matrix 24x24 singular. Msc nastran, patran tutorial modal frequency response, enforced base motion. Nastran, which is the standard analysis software in this industry. Dmigbdf requests global matrix export in dmig format to the bulk data output file. Simplification of damping specification that allows for new damping formulations such as hybrid damping. Nei nastran module nel3 advanced dynamics nei software. A long thin cantilevered plate has a concentrated mass suspended from its free end by two parallel springs.431 165 592 1152 480 598 927 167 1252 255 1231 1519 555 1525 669 1094 455 47 1313 43 490 982 1329 336 9 894 1425 908 1474 443 412 108 1480 1354 880 510 230 1002 402 930