Model reference adaptive control specification for a steam heated finned tube heat exchanger

Model reference adaptive control was used to improve the dynamic performance as the system undergoes changes in its describing transfer function. Outlet coolant temperature was regulated by steam flow in a direct digital control feedback loop, and process identification was carried out in closed loop. A prespecified dynamical behavior was imposed upon the system by adjustment of the control algorithm parameters. The process output is subsequently forced to track a model unit step set point response. Simulation studies were conducted with a realistic nonlinear mathematical model for the heat exchanger system. The nonlinear process is modeled by a second-order transfer function with deadtime (linear model). Process identification based upon quasilinearization, maximum likelihood, generalized least squares, and Kalman's pulse transfer function method was achieved to obtain linear discrete process models at three different operating conditions in each of three conventional feedback control modes.