An improved scheduling heuristic algorithm for no-wait flow shops on total flow time criterion

Since the no-wait flow shop scheduling problems have been proved to be NP-hard, heuristic procedures are considered as the most suitable ones for their solution, especially for large - sized problems. We present a constructive heuristic for minimizing total flow time criterion in no-wait flow shop scheduling problems. The proposed heuristic is based on the assumption that the priority of a job in the sequence is given by the sum of its processing times on the bottleneck machine(s) for selecting the initial sequence of jobs. The final sequence is based on the principle of job insertion for minimizing the total flow time. The computational results show that the proposed heuristic significantly outperforms the existing heuristics, while not affecting its computational CPU time.