Διερεύνηση της συμπεριφοράς έναντι καταστροφικής καταπόνησης λεπτότοιχων δομικών στοιχείων προφίλ αλουμινίου

Χατζηιωάννου, Φίλιππος; Chatziioannou, Filippos Jr

dc.contributor.author	Χατζηιωάννου, Φίλιππος	el
dc.contributor.author	Chatziioannou, Filippos Jr	en
dc.date.accessioned	2021-11-03T11:10:24Z
dc.date.available	2021-11-03T11:10:24Z
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/54022
dc.identifier.uri	http://dx.doi.org/10.26240/heal.ntua.21720
dc.description	Εθνικό Μετσόβιο Πολυτεχνείο--Μεταπτυχιακή Εργασία. Διεπιστημονικό-Διατμηματικό Πρόγραμμα Μεταπτυχιακών Σπουδών (Δ.Π.Μ.Σ.) “Επιστήμη και Τεχνολογία Υλικών”	el
dc.rights	Default License
dc.subject	Thin-walled tubes	en
dc.subject	Energy absorption	en
dc.subject	Aluminum	en
dc.subject	Ls-Dyna	en
dc.subject	Axial crushing	en
dc.subject	Αξονική καταπόνηση	el
dc.subject	Λεπτότοιχοι σωλήνες	el
dc.subject	Αλουμίνιο	el
dc.subject	Τετραγωνική διατομή	el
dc.subject	Αξονική κατάρρευση	el
dc.title	Διερεύνηση της συμπεριφοράς έναντι καταστροφικής καταπόνησης λεπτότοιχων δομικών στοιχείων προφίλ αλουμινίου	el
dc.title	Investigation on the crush behaviour of thin-walled aluminium components	en
heal.type	masterThesis
heal.classification	Mechanical engineering	en
heal.language	el
heal.access	campus
heal.recordProvider	ntua	el
heal.publicationDate	2021-06
heal.abstract	This study investigates the crashworthiness performance of thin-walled square aluminium tubes with triggers. Quasi-static axial crushing tests of specimens were conducted first, and then numerical models were built to simulate testing using the explicit non-linear finite element code Ls-Dyna. Such structures are used as energy absorbing devices in a wide range of vehicles and thus this study is being conducted in order to discover ways of improving the existing vehicle passive safety in order to prevent deaths and major injuries due to accidents. The concept of energy absorbing devices in vehicles has been first explored in the aeronautical sector at the beginning of the past century. Since then, great progress has been achieved. Apart from steel, aluminium and composites are now used for the construction of energy absorbers. Further, the modern design involves the use of filler materials (e.g. foams), multi-cell layouts as long as material hybridization as a means to improve the crashworthiness performance of such devices. What is more, studies have been conducted for a wide range of loading conditions to better understand the crushing behaviour. Despite the advantages of the aforementioned configurations, the most widespread absorbers are still the thin-walled metallic tubes for attributes such as low cost and ease of fabrication. After a targeted review of the literature concerning thin-walled metallic tubes with triggers, the crushing mechanisms related to the present study are being outlined in detail. Specimens of tubular structure with square cross section and triggers at the corners were fabricated and tested in a Universal testing machine, under quasi static conditions. Numerical models were built and then solved using the explicit non-linear FE code Ls-Dyna. The numerical simulation followed closely the experiments in both deformation patterns and crashworthiness parameters. The effect of notching was found to have a negligible effect on both deformation patterns and energy absorption. Further commentary on the deformation mechanisms and crashworthiness parameters was given and useful conclusions for axially crushed square tubes with triggers were drawn.	en
heal.advisorName	Μανωλάκος, Δημήτριος	el
heal.advisorName	Manolakos, Dimitrios Jr	en
heal.committeeMemberName	Μανωλάκος, Δημήτριος	el
heal.committeeMemberName	Κόλλια, Κωνσταντίνα	el
heal.committeeMemberName	Μαρκόπουλος, Άγγελος	el
heal.academicPublisher	Εθνικό Μετσόβιο Πολυτεχνείο. Σχολή Μηχανολόγων Μηχανικών	el
heal.academicPublisherID	ntua
heal.numberOfPages	139 σ.	el
heal.fullTextAvailability	false
heal.fullTextAvailability	false