Heat and mass transfer characteristics of direct contact membrane distillation under marine sloshing: Numerical modeling and predictive correlations

Membrane distillation (MD) has significant potential for freshwater production in dynamic marine environments. However, existing studies mainly focus on static operating conditions, leaving the transient heat and mass transfer response to sloshing-induced disturbances insufficiently understood. To address this gap, a coupled multiphysics numerical model of a direct contact membrane distillation (DCMD) system under multiple degrees of freedom (DOF) marine sloshing is established and validated against simulated marine sloshing experimental data. On this basis, a multifactor statistical method is employed to analyze the effects of operating, geometric, and sloshing parameters on system performance, and predictive correlations incorporating a sloshing correction factor are developed. The simulated marine sloshing experiments show that sloshing enhances transmembrane mass transfer, with the flux enhancement ratio exceeding 100% for all tested motions. Consistent with the experimental observations, the established numerical model accurately predicts the transient feed side outlet temperature and flux enhancement ratio, and the average relative errors between the simulated and experimental results are within 3%. Subsequent multifactor sensitivity analysis indicates that the feed side inlet temperature and flow rate are the dominant factors affecting thermal response and productivity, whereas the sloshing parameters mainly act as secondary regulating variables but exhibit a more pronounced influence on system energy efficiency. Furthermore, the developed predictive correlations, covering both system-level indicators and dimensionless heat and mass transfer numbers, show satisfactory fitting accuracy, with coefficients of determination ( R 2 ) exceeding 0.9. Overall, these results provide reliable quantitative tools for the performance prediction and engineering design of DCMD systems under marine sloshing.