Conceptual Design, Initial Sizing and Sensitivity Analyses of a High Altitude Airship using revised Volumetric Drag

摘要

This paper will describe a methodology that can arrive at the baseline specificationsrnof conventional configuration of a stratospheric airship, given the performance andrnoperational requirements like payload mass, payload power, mission speed,rngeographical location, and altitude of deployment. The empirical relation forrncoefficient of volumetric drag is not accurate for all the geometries of airship hull.rnThe coefficient of volumetric drag is revised for Wang profile shape with a fixedrnfineness ratio of 3.87 based on the data available from flow filed simulations viarncommercial CFD package FLUENT. The flow field simulations are carried out for arnrange of Reynolds numbers between 10~7-10~9. Results obtained using this sizingrnmethodology for some typical operating requirements for stratospheric airships willrnalso be presented. The sensitivity of the airship size and all up weight to some keyrninput parameters will also be brought out.