Week - 8 Mass Scaling

Aim:

Use mass scaling to reduce the runtime of a model and ensure the stability of mass scaling. The hard limit on mass scaling is 8% and stability should be completely intact. This means that two simulations, one with mass scaling and one without should behave exactly the same way. The submission should contain the trials for mass scaling and the data generated henceforth. Both the DT and TSSFAC parameters should be optimized.

Procedure:

The concept of the mass scaling is to reduce the cycle time of the operation by increasing the time step size.

Time step size: It means the step considered by the nodes to perform one cycle. If we multiple with number of cycles then we get dt (time step to generate the output).

Time step size is calculated using the ration of minimum length of the component to the wave number.

So to change the time step size we should change the value of dt2ms value, which represents the mass added to the smaller step nodes. And another factor is tssfac, which talk about making the system stable by reducing the time without any effect to the mass %.

Conclusion:

The optimized values are dt2ms=-1.0e-4 and tssfac =1.0, where the mass % increase is 6.4%

The run time betweeen implict and explicit reduced drastically. In explicit the run time is 14 hrs whereas the runtime in implicit is 10mins