Numerical simulation of liquid-liquid agitated dispersions on the VAX 6520/VP

This work began as a study of the implementation of a liquid-liquid hydrodynamic and mass transfer simulation algorithm on the VAX 6000 model 520 vector processor. A scalar code developed by Riberio et al.³ has proved adequate and accurate to describe the transient and the limiting hydrodynamic steady-state, either of a continuous or of a batch liquid-liquid contactor; it also may be extended to predict the mass transfer performance of this type of system. Using this pre-existing FORTRAN code, we describe some techniques for modifying it in order to take advantage of the VAX 6000 vector architecture. The main thrust of this investigation is to identify the characteristics of the VAX vector processor that affect performance, and to show how that performance information can be used to build optimized algorithms. The nature of the modifications made to the algorithm and their effect on the overall computation time are reported for two types of changes: scalar optimization and vectorization.