Parametric study and response surface analysis of hatch sealing structure based on multi-parameter leakage rate prediction model

Abstract

The aim of this study is to establish a multi-parameter leakage rate prediction model for the sealing structure of large diameter hatches, enabling direct enhancements the hatch’s sealing structure. The model integrates mesoscopic interfacial flow simulations and macroscopic structural deformation simulations to facilitate comprehensive analyses. This approach allows for quantitative assessment of various parameters influencing the leakage rate, including sealing surface morphology, material properties, structural dimensions, and operating environment. A leakage rate test was conducted in which several parameters were adjustable, validating the proposed model’s accuracy through close agreement between experimental measurements and theoretical predictions. The effects of four parameters were examined: bolt preload force Fn, cover flange thickness tc, gasket thickness tg, and gasket inner diameter Di,g. The leakage rate was found to be the most sensitive parameter to changes in Fn when compared to tc, tg, and Di,g. The effects of tc, tg, and Di,g grew more prominent only at pressures exceeding 1.0 MPa. With leakage rate as the response quantity, response surface analysis was implemented to clarify the interaction between the four parameters. The results indicated that the optimal solutions for two cases with design pressures of 0.66 MPa and 2.0 MPa were essentially similar; differences were observed in their respective worst-case scenarios. Under high pressure and medium-level preloading, hatches should be designed to avoid cases wherein two or three structural parameters simultaneously reach lower levels.