Coupled Temperature-Displacement Modelling of Injection Stretch Blow Moulding of PET bottles using Buckley Model

This study presents a fully coupled temperature–displacement finite element modelling of the injection stretch-blow moulding (ISBM) process of polyethylene terephthalate (PET) bottles using ABAQUS with a view to optimising the process conditions. A physically-based material model (Buckley model) was used to predict the mechanical behaviour of PET at temperatures slightly above its glass transition temperature. A model incorporating heat transfer between the stretch rod, the preform and the mould was built using axisymmetric solid elements. Extensive finite element analyses were carried out to predict the deformation, the distribution and history of strain and temperature during ISBM of a 20 g–330 ml bottle, which was made in an in situ test on a Sidel SB06 machine. Comparisons of numerical results with the measurements demonstrate that the model can satisfactorily model the sidewall thickness and material distributions. It is also shown that significant non-linear differentials exist in temperature and strain in both bottle thickness and length directions during the process. This justifies the employment of a volume approach to accurately predict the final mechanical properties of the bottles governed by the orientation and crystallinity which are highly temperature and strain dependent.

Famine and land in Ireland and India 1845-1880: James Caird and the political economy of hunger

The perception of Ireland and India as ‘zones of famine’ led many nineteenth-century observers to draw analogies between these two troublesome parts of the British empire. This article investigates this parallel through the career of James Caird (1816–92), and specifically his interventions in the latter stages of both the Great Irish Famine of 1845–50, and the Indian famines of 1876–9. Caird is best remembered as the joint author of the controversial dissenting minute in the Indian famine commission report of 1880; this article locates the roots of his stance in his previous engagements with Irish policy. Caird's interventions are used to track the trajectory of an evolving ‘Peelite’ position on famine relief, agricultural reconstruction, and land reform between the 1840s and 1880s. Despite some divergences, strong continuities exist between the two interventions – not least concern for the promotion of agricultural entrepreneurship, for actively assisting economic development in ‘backward’ economies, and an acknowledgement of state responsibility for preserving life as an end in itself. Above all in both cases it involved a critique of a laissez-faire dogmatism – whether manifest in the ‘Trevelyanism’ of 1846–50 or the Lytton–Temple system of 1876–9.