Modelling: Nature and Use

Engineering of products and processes is increasingly “model-centric”. Models in their multitudinous forms are ubiquitous, being heavily used for a range of decision making activities across all life cycle phases. This chapter gives an overview of what is a model, the principal activities in the formation of a model for a specific purpose and the wide range of problem types that characterise the application areas of those models. In particular, a strong systems and life cycle perspective is presented which emphasises the development and application of models within each of the life cycle phases. The modelling goal is emphasised and discussed in terms of a triplet of: the model, amodel application and the type of system under study. The much wider length and time scale phenomena now being addressed through modelling is discussed. This change has broadened modelling practice from a dominance on the mesoscale phenomena towards higher and lower scales. This breadth in scale-spread of the partial models being developed presents significant challenges around multiscale modelling and the integration frameworks for such complex system modelling. A number of these frameworks are given in the chapter and are discussed. Throughout the chapter a number of taxonomies around model types and formshelp summarise the current modelling situation within much of product and process applications.