A conceptual study for a computational simulator of material circulation in a CEEF was performed. CELSS such as the CEEF (Closed Ecology Experiment Facility) which is under construction in the Institute for Environmental Sciences have many physico-chemical devices. To simplify their programming, many physico-chemical devices were classified into several function groups using C++, a specially designed programming language to support the object oriented programming technique.
Based on the classifications, the simulation software was made and the simulation was performed. The simulation results predict that stable operation of CEEF can be obtained.