This study investigates the application of a recently developed
construct, the Uniform Trigonometrization Method (UTM), to the singular
control problems in chemical engineering. The UTM involves minimal
modifications to the original problem, thereby generating near-singular
control solutions that can be used for conceptual design and serve as an
alternate to direct techniques like nested and simultaneous approaches.
Eight classical singular control problems with known analytical
solutions and three complex singular control problems from chemical
engineering domain are solved in this study. The results obtained using
the UTM for these problems are found to match well with the literature
and are of higher resolution as compared to the results obtained using a
direct pseudospectral based solver. The ability of the UTM to handle
complex chemical engineering problems with both singular controls and
state path constraints has also been demonstrated in this study.