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[FAQ]

The default unit of time is always “second” in WB LS-DYNA. It cannot be changed to millisecond manually. However, you can trick the program to use different system of units such as using millisecond to replace second. For example, if the Unit System in Solver Controls under Analysis Settings is mks (meter, kg, second), you want to treat the second as millisecond. When you input velocity, 1 m/s will be 1 * 0.001 = 0.001 m/ms. The force of 1 N input will be 1/10^6 = 0.000001 kg*m/ms^2. When you input material properties, the bulk modulus of 1 Pa will be 1/10^6 = 0.000001 kg*m/ms^2/m^2. After the model is solved, the stress output of 1 Pa is actually 1 kg*m/ms^2/m^2 = 1 MPa. The velocity output of 1 m/s is actually 1 m/ms = 1000 m/s. Thus, you can use the existing system of units to run the simulations with assumed different time units.