sol600subcase求解设置patran

308 Adaptive Load Incrementation with Arclength (SOL 600 only) Adaptive Increment Parameter Description Arclength Method Selects the arclength root procedure: Crisfield, Riks/Ramm, Modified Riks/Ramm, or Crisfield-Modified Riks/Ramm. The default is Modified Riks/Ram. If None is selected the form updates as shown (p. 304). For Transient Dynamics, this is the only option available for adaptive load incrementation. Automatic Cutback This feature is ON by default. If an increment does not converge, a restart from the last increment cuts the increment size in half. Number of Cutbacks This is associated with Automatic Cutback. This parameter determines how many times a cutback is allowed. Initial Fraction of Load Applied to 1st Increment This is the fraction of the total load that should be applied in the first iteration of the first increment. Max. Fraction of Load Applied in Any Increment This is the maximum fraction of the load that can be applied in any increment. Max/Min Ratio Arc Length / Initial Arc Length Used to define the minimal arclength. The default is 0.01. Static 309CHAPTER 3 Running an Analysis Fixed Load Incrementation Max. # of Increments Defines the maximum number of increments. Program will end if this value is exceeded. Total Time This is the total time of the analysis for a particular step. It defaults to one (1) if left blank for static load cases. For time dependent load cases, the total time is the length of time between distinct time points if left blank. Otherwise the actual value is used (not recommended because it can’t be variable). Fixed Increment Parameter Description Automatic Cutback Applies to Nonlinear Statics only. It is ON by default. If an increment does not converge, it allows for a restart from the last increment cuts the increment size in half. Number of Cutbacks This is associated with Automatic Cutback. This parameter determines how many times a cutback is allowed. Number of Increments or Number of Steps For Statics and Creep this is the number of increments specified in the NLAUTO option. Or for Transient Dynamics defines the number of steps to use throughout the analysis for Fixed time step type. Default is 10. Total Time For Statics, this enters the NLAUTO option which is the total time as defined in this widget. For Transient Dynamics this is the total time. For Creep, the total time is either placed in the 2nd data block of a CREEP INCREMENT option or the total time is divided by the Number of Increments, if this value is present, and the incremental time is written to the 2nd data block of the CREEP option. Adaptive Increment Parameter Description Static Transient Dynamic 310 Iteration Parameters This subordinate form appears when the Iteration Parameters button is selected on the Static, Transient Dynamics, or Creep subcase parameter forms. Unless otherwise specified all paramater references apply to the NLSTRAT entry for the form on the left (SOL600) and NLPARM for the form on the right. Gamma / Beta For Transient Dynamics only. Default is 0.5. Time Integration Scheme For Transient Dynamics, the Houbolt and Central Difference cannot be selected. Indicates the time integration scheme to use in dynamic analysis.Single Step Houbolt is the default. Minimum Iteration per Increment Enter these values for a SOL 400 run. For SOL 600 these values are defined on the Iteration Parameters (p. 310) form. Maximum Iteration per Increment Enter these values for a SOL 400 run. For SOL 600 these values are defined on the Iteration Parameters (p. 310) form. Matrix Update Method This is the method for controlling stiffness updates. This is the KMETHOD field on the NLPARM entry for SOL 400 runs. Fixed Increment Parameter Description 311CHAPTER 3 Running an Analysis SOL 600 Iteration Parameter Description Proceed if not Converged Forces the analysis to proceed even if the increment did not converge. Non-positive Definite This forces the non-positive definite flag (IKNONPOS param) ON in the NLSTRAT option. A new NLSTRAT option is written for each step if a change in this flag has been detected from Subcase to Subcase. Iteration Method Indicates the iteration method (IKMETH param) to be used. This is can be set to Full Newton-Raphson, Modified Newton- Raphson, Newton-Raphson with Strain Correction, or Secant Method. Full Newton-Raphson is default. Max # of Iterations per Increment Defines the maximum number of iterations (MAXREC param) allowed for convergence in any increment. This number is negative if Proceed if not Converged is ON from the Solution Parameter form. Minimum # of Iterations per Increment This specifies the minimum number of iterations per Increment (MINREC param) option. It can be an integer number zero or greater. If this is set greater than zero, every increment will perform at least this many iterations. Desired # of Iterations per Increment Defines the number of desired iterations in an increment (ATRECYC param) which is placed on the NLSTRAT option. If the actual number of iterations is less than this value, this will be used to figure out how much to increase the load step for the next increment. In a similar manner if the actual number of iterations is greater than this number (but less than the Max # of Iterations per Increment, this will be used to decrease the load step in the next increment. Obviously if Adaptive incrementation is not specified, this data will not be used. Tolerance Method Defines the tolerance method to be used (CONVTYP param). This can be set to Residual, Incremental Displacement, or Incremental Strain Energy. Residuals/Displacements And Or If you want the Tolerance Method to use both Residuals and Displacements to determine convergence set this to And. If you want either one or the other to determine convergence, set this to OR. If Tolerance Method is set to Residual or Displacement, then these two toggles are enabled. Both are OFF by default. If one is ON, the other is OFF. These toggles work in combination with Tolerance Method. If both are OFF, then Tolerance Method determines what is written. Error Type Indicates the type of error to use (IRELABS param). This can be set to Relative or Absolute or Both. Automatic Switching This controls automatic switching (the AUTOSW param on the NLSTRAT option) between Residuals and Displacement tolerances if one or the other fails to converge. 312 Residual Tolerances Values and labels in this frame depend on the Tolerance Method and Error Type setting and are discussed below. Relative Residual Force Relative Displacement Relative Energy Relative Residual Moment Relative Rotation The value of this widget (default is 0.1 on force) is written to the RCKI param. Minimum Reaction Force Minimum Displacement Minimum Reaction Moment Minimum Rotation Maximum Residual Force Maximum Displacement Maximum Residual Moment Maximum Rotation The value of these widgets (default is blank) is written to the appropriate MAXxx or MINxx param. SOL 400 Iteration Parameter Description Displacement Error Load Error Work Error Vector Componet Method Length Method If any of these toggles are ON, then the appropriate CONV=U, P, W, V, or N is written to the NLPARM entry to activate the repective convergence criteria. Displacement Tolerance Load Tolerance Work Tolerance Specifies the tolerance value if the above corresponding toggles are activated. This is written in the EPSU, EPSP, and EPSW fields of the NLPARM entry. Leave blank for default values. Maximum Divergence Condition Maximum Number of Quasi- Newton Correction Vectors Maximum Number of Line Searches Fraction of Effective Stress Line Search Tolerance Maximum Number of Bisections Maximum Incremental Rotations Specifies the MAXDIV, MAXQN, MAXLS, FSTRESS, LSTOL, MAXBLS, and RTOLB fields of the NLPARM entry. It is recommended to use the default values. Please consult the MD Nastran Quick Reference Guide for more information. SOL 600 Iteration Parameter Description