Study on the Diffusion Mechanisms of Methanol Leakage in Confined Spaces

With the rapid expansion of methanol-powered shipping, the emphasis within the industry has increasingly been placed on ensuring the operational safety of these alternative fuel vessels. In this study, the mixture and realizable k-ε models are adopted to simulate the liquid methanol leakage model, and the predictive accuracy of the model is verified through a comparative analysis with experimental results. Given the complexity of ship cabins, a comprehensive exploration of the leakage and diffusion behaviors of methanol under different ambient temperatures, main engine surface temperatures, and leakage port sizes is conducted. The research findings show that an increase in ambient temperature significantly accelerates vapor diffusion by enhancing evaporation and strengthening the wall-accumulation effect. In contrast, an increase in the main engine surface temperature mainly causes local vapor stagnation and has a relatively limited impact on the overall diffusion pattern. An increase in the leakage orifice diameter directly increases the leakage volume, shortens the diffusion period, and promotes nonlinear growth of the vapor height. The research results can not only provide a theoretical basis for the design of cabin structures and ventilation systems of methanol fuel ships but also be applied to the risk prevention and control of methanol leakage scenarios on ships.