Simulation and Analysis of Fluid–Solid–Thermal Unidirectional Coupling of Near-Space Airship

Abstract

Based on the biaxial experiment data of the membrane material under hot and cold conditions, the mechanical properties calculation model of envelope material was established with consideration of the effects of varying stress ratios, stress magnitudes and temperatures on the mechanical properties of near-space airship material. Using the heat source model, Computational Fluid Dynamics (CFD) simulation, User-Defined Function (UDF), structural finite element analysis software and the user subroutine of an airship to define the behaviour of fabric material, the fluid–structure–thermal coupling model of airship envelopes was established. In addition, a near-space airship was selected as the research subject to calculate the diurnal temperature differences during the summer solstice and analyse the diurnal temperature distribution of the envelope. Under controlled environmental conditions, the deformation law of the near-space airship under the influence of fluid–structure–thermal coupling was calculated and summarised. The present fluid–solid–thermal coupling model takes into account the anisotropy of materials, temperature, stress magnitude, stress ratio and other influencing factors, which can more accurately reflect and predict the stress–strain distribution and the deformation law of near-space airships.

Optimization Design and Experimental Verification for the Mixed-Flow Fan of a Stratospheric Airship

“…In this study, a stratospheric mixed-flow fan [31] is used as the research object, and the improvement of fan efficiency and static pressure rise is used as the optimization objectives. The L16(4 5 ) orthogonal test is adopted to conduct the multi-parameter and multiobjective optimization study on the fan. Finally, the accuracy of the numerical analysis method and the rationality of the fan design are verified by combining the performance tests.…”

“…A stratospheric airship, an aerostat that can stay in near space (18-22 km) for an extended duration, can carry several loads to achieve communication, navigation, observation, early warning, and other functions [1][2][3]. It has a high cost-effectiveness ratio, broad coverage, and strong load capacity, demonstrating broad application potential [4][5][6].…”

Theoretical and Simulation Analysis of a Thin Film Temperature Sensor Error Model for In-Situ Detection in Near Space

“…The temperature sensor directly exposed to the air compresses the air in front of it, and the gas temperature rises, that is, aerodynamic heat. Therefore, the temperature field where the temperature sensor is located is not the real atmospheric temperature field, but the temperature field superimposed by aerodynamic heat [17,18].…”

Multidisciplinary Optimization and Analysis of Stratospheric Airships Powered by Solar Arrays

“…With potential in military and civil applications including communication, surveillance, observation and scientific research, there is a growing interest in studying stratospheric airships in recent years [1][2][3]. Stratospheric airships generally remain aloft at specific altitudes (18~22 km) for long endurance (several months) using buoyancy of lighterthan-air gas [4][5][6].…”