Integrated System Architecture Development Framework and Complexity Assessment

Abstract

Systems engineering is the popular top-down systematic approach to understand and develop complex systems. There is a gap between the systems engineering activities and engineering analysis in major system development processes. This paper presents an integrated MBSE development framework with definite and indefinite modeling capabilities to bridge this gap. The framework uses SysML, a system modeling language, to describe its elements from the system architecture’s perspective. A detailed workflow is presented that guides the engineer throughout the modeling process. The workflow establishes traceability throughout the framework. This research uses Functional Mock-up Interface (FMI) standards to integrate system engineering activities and engineering analysis. A district cooling system case study is presented to demonstrate the framework’s capabilities in enabling the system into existence. The system architecture model was developed using SysML language in the Cameo Enterprise Architecture environment. The engineering analysis model used object-oriented Modelica language in the Dymola environment. The analysis results show that the district chiller model developed using Modelica produces chilled water below 6.6 degrees Celsius, satisfying the district chiller’s system requirement. The exponential trend in the system architecture’s complexity pattern is measured and analyzed using complexity assessment techniques. The results show that the structural complexity of the system increases steadily from 2.7080 to 8.1241. However, the behavioral complexity increases drastically from 1.7915 to 59.2686 in the problem domain.