Safety Analysis of Hydrogen Internal Combustion Engine Hybrid System Based on FRAM-ISM

To address the requirements of carbon emission reduction and green transformation in the aviation industry, this study innovatively constructed the FRAM-ISM coupling model for safety risk analysis of Hydrogen Internal Combustion Engine Hybrid Systems. This study integrates the dynamic nonlinear modeling advantages of the Functional Resonance Analysis Method (FRAM) with the static hierarchical analytical capability of the Interpretive Structural Model (ISM). This coupling model systematically reveals the risk transmission mechanism within the functional network of the Hydrogen Internal Combustion Engine Hybrid System. Based on system decomposition of 14 functional units (covering core components such as hydrogen storage devices, internal combustion engine modules, and power batteries), a FRAM model is first established to identify resonance propagation paths in dynamic interactions. Then, the ISM method is used to construct a five-level hierarchical system, and the importance of module structure is quantitatively evaluated using reachability matrices. Research has found that the high structural importance of engine control systems has become a critical and vulnerable node, and their failure will trigger a risk of global functional resonance; The hierarchical weights of the cooling system and sensor system exhibit significant environmental sensitivity characteristics. On this basis, sensitivity analysis was used to propose a multi-level fault-tolerant architecture, develop dynamic energy management strategies, and implement differentiated calibration cycles, effectively verifying the methodological advantages of the FRAM-ISM coupling model in complex system risk assessment, and providing an innovative analytical framework for reliability optimization of aviation hydrogen energy systems.