The Initial Values node adds initial values for the dependent variables that can serve as an initial condition for a transient simulation or as an initial guess for a nonlinear solver. If you need to specify more than one set of initial values, you can add additional
Initial Values nodes.
Enter a value or expression for the Initial value for u,
u (dimensionless) and the
Initial time derivative of u,
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(SI unit: 1/s). The defaults are 0 for both dependent variables.