Dynamic simulation and optimization of multitubular reactors

The numerical simulation of multitubular reactors is a challenging application due to the complexity of the interactions among elements and to the scale of the resulting DAE system. Traditionally, several simplifications are made in order to permit simulation of the system, frequently compromising simulation results. In this contribution, the resolution of a detailed heat transfer-reaction model of a multitubular reactor is presented. The resulting large-scale DAE comprising about 200,000 equations was integrated through BDF technique, employing a modified version of the DASPK code. Good vector and parallel performance were observed in the test runs carried out on a shared memory, parallel-vector-processor (PV-P) platform, the Cray J98, installed at the Center for Parallel Computations (NACAD) at COPPE/UFRJ. Also, some preliminary results on optimization of operating conditions of the reactor are presented. High performance computation has been crucial for the success of this work. The careful implementation of the chosen numerical methods, totally adapted to the platform employed, made computationally feasible the dynamic simulation of the multitubular reactor. As a typical example the partial oxidation of the benzene was considered.