: The Open Reflective Component Architecture (ORCAN) is a component based software platform for Simulation software. It enables to build applications out of runtime exchangeable components. One purpose of this framework is to introduce advanced software design techniques in simulation software for a longterm distributed development process. The other benefit of this framework is a predefined set of components for standard simulation purposes, which can be seen as a suggestion for a simulation middleware platform. In this paper we will present the basic design of ORCAN. As an example application we have implemented a parallel heat equation solver.