Singular optimal control strategy for a fed‐batch bioreactor: Numerical approach

The production of bakers' yeast in a fed‐batch bioreactor can be maximized by controlling the substrate feed rate. This leads to a singular optimal control problem. An exact solution initially based on a heuristic argument and later quantified by the generalized Legendre‐Clebsch convexity condition is obtained. A numerical technique, obtained by embedding the singular problem in a sequence of nonsingular problems that converge to the singular one in a limit as ϵ → ∞ is demonstrated.