Comparative study on thermodynamic performance of liquid hydrogen storage insulation system incorporating vapor-cooled shield with para-ortho hydrogen conversion by one-dimensional and quasi-two-dimensional model

As the pivotal technology for large-scale utilization of hydrogen, hydrogen storage is bracing itself to significant challenges related to heat leakage. To enhance the insulation performance of liquid hydrogen storage insulation system (LHSIS), spray-on foam insulation (SOFI), variable density multilayer insulation (VDMLI) and vapor-cooled shield (VCS) are commonly employed. This study established an LHSIS that integrated SOFI, VDMLI and VCS with continuous para-ortho hydrogen conversion (POC). The insulation performance was evaluated by one-dimensional (1D) model and quasi-two-dimensional (quasi-2D) model respectively. Additionally, the impacts of single VCS (S-VCS) and double VCSs (D-VCSs) were analyzed. Model validation results indicated that the accuracy of quasi-2D model is greater than 1D model. The heat transfer rate and temperature variations within VDMLI and VCS were calculated by quasi-2D model, revealing the heat transfer mechanism of insulation structures incorporating S-VCS/D-VCSs with POC. For the purpose of instructing the application of 1D model by comparing with quasi-2D model, the optimization of VCS location was conducted. The maximum tolerance of 1D model in predicting the optimized VCS location is 21.12% compared to quasi-2D model. Notably, the optimized VCS locations were identical for LHSIS incorporating S-VCS with POC. Furthermore, the maximum advantage of D-VCSs over S-VCS and the cooling effect of POC are respectively overstated by 9.10% and -6.85% for 1D model compared to quasi-2D model.