Envelope parameter sensitivity analysis on fluid-thermal-structural coupling characteristics of stratospheric non-rigid airship

The research on fluid-thermal-structural coupling effect of stratospheric non-rigid airships is crucial for ensuring long-endurance performance. However, there remains a lack of comprehensive analytical studies on the quantitative parameter sensitivity related to this coupling effect. In this study, an iterative analysis method based on buoyancy-gravity re-equilibrium was developed to investigate the fluid-thermal-structural coupling characteristics of non-rigid airships. By integrating both single-parameter and multi-parameter sensitivity analysis methods, the sensitivity of envelope thermal and structural parameters—such as absorptivity, emissivity, elastic modulus, and thickness—on the coupling effect was systematically evaluated. Both the independent and synergistic effects of these envelope parameters were examined. Results indicate that the elastic modulus and thickness of the envelope have a significantly greater influence on structural deformation compared to absorptivity and emissivity. Conversely, the impact of elastic modulus on the maximum equivalent stress is less pronounced than that of absorptivity and emissivity. Additionally, the synergistic interaction between structural and thermal parameters was found to significantly affect the diurnal volume variation and structural deformation. These sensitivity analysis results provide valuable guidance for the design and flight testing of long-endurance stratospheric non-rigid airships.