Week - 8 Mass Scaling

  AIM:

     To perform the simulation by reducing and stabilizing the run time with the help of mass scale factor

  OBJECTIVE:

     $ To understand the motive of computing time with and without a mass scale factor.

      $ By ensuring the stability of mass scaling at 8%.

       $ Comparing implicit and explicit value runtime.

 PROCEDURE:

     STEP 1:

              Given model.

     

 STEP 2:

      CASE 1:

            EXPLICIT ANALYSIS (With mass scale).

        If the stability is a problem with the default TSSF of 0.9,0.7 .If you have reduce the TSSF you can increase[DT2MS] proportionally so that their product, and hence timestep is unchanged.

 ITERATION 1:

              Here, the TSSFAC and DT2MS value has been given.

     

           The estimated time is 45hrs 45 min for this TSSFAC and DT2MS.

       

  ITERATION 2:

             Here, the TSSFAC and DT2MS value has been given.

       

                   The estimated time is 55 hrs 17 min

        

  ITERATION 3:

                   Here, the TSSFAC and DT2MS value has been given.

         

                The estimated time is 32 hrs 22 min

          

  ITERATION 4

                         Here, the TSSFAC and DT2MS value has been given.

            

                  The estimated time is 3hrs 37 min

           

 ITERATION 5:

                     Here, the TSSFAC and DT2MS value has been given.

           

                       The estimated time is 4hrs 2min

          

   ITERATION 6:

                        Here, the TSSFAC and DT2MS value has been given.

          

                  The estimation time is 19 hrs 7min

         

   ITERATION 7:         

      Here, the TSSFAC and DT2MS value has been given. 

                               

                 The estimated time is 21 hrs 20min

            

    ITERATION 8:

                  Here, the TSSFAC and DT2MS value has been given.

         

              The estimated time is 19 hrs 37min.

         

    CASE 2:    (WITHOUT MASS SCALE)

                         IMPLICIT _SOLVER

         

        

        

  STEP 3:

        The histogram plot for DT2MS and TIME.

            

         

        

  CONCLUSION:

           $ As we know, FEM is used to calculate the state of a given system at a different time from the current time. In Implicit analysis each time step has to converge ,but we can set pretty long time steps and it based on iteration.Explicit on the other hand doesnt have to converge each time step,but for the solution to be accurate time step must be small. Though the running time for implicit analysis is shorter than the explicit analysis method because the timestep is defined larger in implicit analysis and we have used constant timestep formulation.

         $  From the above cases,i have learned mass scaling and obtained 8% by varying the DT2MS values along with TSSFAC.