APMonitor

Sequential Simulation

The DBS file parameter imode is used to control the simulation mode. This option is set to 7 for dynamic simulation.

NLC.imode = 7

Like steady-state simulation, sequential simulation requires a square problem with no degrees of freedom (n_eqn=n_var). It is also different than the simultaneous approach in that only one time step ahead is solved successively. Sequential simulation has many useful purposes including

• Run through a large amount of historical data
• Investigate step response characteristics of a nonlinear model
• Simulate process changes for design, trouble-shooting, or planning
• Perform what-if scenarios
• Simulate a virtual process

Sequential simulation is one of the easiest dynamic modes to configure and run. The requirement for a square problem facilitates model convergence as the solver has only to achieve feasibility with the equality constraints.