A Design Pattern Framework for Material and Energy Flow Modelling: Enhancing Reusability, Consistency, and Multi-Perspective Life Cycle Assessment

Material and energy flow models (MFEMs) are widely used to support life cycle assessment (LCA) and sustainability analyses; however, increasing system complexity often results in models that are difficult to structure, reuse, and adapt across analytical perspectives. This study proposes a structured design pattern framework for MFEMs aimed at improving model consistency, modularity, reusability, and multi-perspective applicability. A mixed-method research approach was applied, combining targeted literature review, practitioner questionnaires, expert interviews, and modelling experience to identify recurring modelling challenges and formalize reusable modelling solutions. The framework was evaluated through comparative case studies in mining, agricultural, and industrial systems. Results demonstrate improvements in structural clarity, model reusability, and the integration of environmental, economic, and social assessment perspectives within a single modelling environment. The findings further highlight the relevance of modular and reusable modelling structures for digital LCA, circular economy applications, and emerging sustainability assessment environments. Overall, the proposed framework contributes to advancing more interoperable, transparent, and digitally enabled material and energy flow modelling practices.