Object-oriented modelling and simulation of batch plants

In this paper, the modelling and simulation of recipe driven multipurpose chemical or biochemical plants using an object oriented approach is described. A data model is presented which enables the description of all important aspects of batch plants: the model of the plant (reactors, tanks, pipes, separation units etc.), the batches of material and the dynamics of their transformation, and the recipe driven sequential production process. Batch plants are complex hybrid systems (Cellier et al. (1993), Clark and Joglekar (1992)) because many different components with associated continuous dynamics are involved, the production sequence is event-driven, continuous and discrete state variables must be used to describe the production process, and the structure of the system and the number of state variables change over time.