Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE credits
The main subject of the thesis is impact simulation of an elastic fuel tank
reinforced with a polymer exoskeleton. Thanks to its light weight and failure
resistance, this type of design shows potential to be used in aerospace
applications. The simulation imitates a drop test from the height of 20 m
on a rigid surface, in accordance with Military Handbook testing guidelines
for fuel tanks. The focus is on establishing the best practices for modelling
and solving this type of problems. The computational methods are tested
on a generic model of a rectangular prismatic tank with rounded edges. The
walls of the tank are made of a combination hyperelastic rubber material orthotropic
fabrics. The simulation is performed for the 70% and 100% water
lled tank. All calculations are performed using the Altair HyperWorks 13.0
software suite, in particular the RADIOSS solver and OptiStruct Solver and
Optimiser. The criteria for evaluation of model and simulation quality are
suggested. Comparison is made between various uid (ALE and SPH) and
solid (composite and hyperelastic) modelling approaches. Material parameters
are found using the least-squares t to the experimental measurements.
The nal, most robust and accurate model serves as a basis for establishing
a design optimisation procedure, aiming at reduction of mass of tank
components while ensuring the structural integrity. Furthermore, the advantages
and drawbacks of di erent modelling approaches are discussed. The
main conclusions from the study are summarised and suggested directions
for future work are given.
2015. , 85 p.