A Prototype Computer-Aided Modelling Tool for Life-Support System Models 901269

Based on the canonical decomposition of Physical-Chemical-Biological (PCB)-systems, a prototype kernel has been developed to efficiently model alternative life-support systems. It supports (i) the work in an interdisciplinary group through an easy-to-use mostly graphical interface, (ii) modularized object-oriented model representation, (iii) reuse of models, (iv) inheritance of structures from model object to model object, (v) model data base. The definition of a PCB-system model splits in different phases: (i) definition of the topology using primitive systems (simple thermodynamic systems, chemical systems, information systems and transfer models supplemented by state variable transformations and physical property models); (ii) definition of the species and their occurrence in the different parts of the system; (iii) definition of the transfer laws and kinetics as well as the choice of the particular model for the physical properties; (iv) adding the dynamic behaviour of the information processing units. The kernel is implemented in Modula-II and presently operates on an IBM PC.