Adhesive junction modelling of a super-pressure balloon

Abstract

Long duration super-pressure balloon design and manufacturing is a great challenge for the Centre National d'Etudes Spatiales in scientific ballooning. They are made of 50 μm thick polymer films polyethylene terephtalate/polyamide/polyethylene terephtalate which are joined with 23 μm thick adhesive polyethylene terephtalate bands. To date, during flight missions, a major problem appears: some balloons explode prematurely. This is why this study deals with the mechanical behaviour of the stratospheric pressurized balloons and particularly with the assembly of the constitutive films material. First, a nanoindentation test campaign makes it possible to identify the elastic properties of the materials at two different temperatures. Then, a nominal assembly is simulated in two stages: two-dimensional and three-dimensional. Finally, the factorial design method combined with finite-element simulations was used to study the influence of the various conception parameters on the mechanical behaviour of the assembly.

Experimental characterization and damage identification of polymeric film constituting stratospheric super pressurized balloons

“…To find out more about the behaviour of their balloons in flight, the CNES has set up research programme into the mechanical behaviour of these structures (12 m diameter super pressurized balloons). The first part of the scientific programme concerned the numerical and experimental simulation of the mechanical behaviour of balloons [2,3,8]. This article deals with the second part of the research programme, which concerns the experimental study of phenomena at the origin of damage to the polymeric film.…”