Abstract




 
   

IJE TRANSACTIONS B: Applications Vol. 27, No. 8 (August 2014) 1307-1316   

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  EXPERIMENTAL AND NUMERICAL STUDIES ON THE CHARACTERISTICS OF SIMPLE AND MULTI-CELL SHAPES OF QUASI-HEMISPHERE THIN-WALLED STRUCTURES
 
M. Parsapour
 
( Received: January 19, 2014 – Accepted: March 06, 2014 )
 
 

Abstract    Thin-walled energy absorbers are used to reduce accident induced damages. In this study, thin-walled stainless steel structures in quasi-hemisphere geometry were subjected under quasi-static loading with Santam 150KN apparatus. Experimental results were compared with results of numerical simulations by LS-DYNA and it was shown that there is a good agreement between experimental and numerical results. Also, the multi-cell quasi-hemisphere specimens were numerically investigated and it was presented that increasing the number of cells increases the absorbed energy. The results showed that Six-cell specimen with the largest diameter and the minimum thickness has the most increase of Specific Absorbed Energy (SAE).

 

Keywords    Thin-walled structure, energy absorber, quasi-hemisphere, multi-cell

 

چکیده    از سازه های جدارنازک به منظور کاهش صدمات ناشی از تصادفات استفاده می شود. در این بررسی، سازه هایی از جنس فولاد ضد زنگ به شکل شبه نیمکره تحت بار شبه استاتیکی توسط دستگاه سنتام قرار گرفتند. نتایچ تجربی با نتایج حاصل از شبیه سازی عددی مقایسه شدند و نشان داده شد که تطابق خوبی بین آن ها وجود دارد. همچنین نمونه های چندسلولی شبه نیمکره مورد بررسی عددی قرار گرفت و نشان داده شد که افزایش سلول ها سبب افزایش انرژی جذب شده می گردد. نتایج نشان داد که نمونه شش سلولی با بیشترین قطر و کمترین ضخامت دارای بیشترین مقدار انرژی جذب شده مخصوص می باشد.

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