Proactive regulation of axial crushing behavior of thin-walled circular tube by gradient grooves. (April 2016)

• Record Type: Journal Article
• Authors: Wei, Yanpeng; Yang, Zhe; Yan, He; Guo, Yacong; Wu, Xianqian; Huang, Chenguang
• Is Part Of: International journal of mechanical sciences. Volume 108/109(2016)
• Page Start: 49
• Page End: 60
• Publication Date: 2016-04
• Subjects: Gradient grooved tube (GGT) -- Proactive regulation -- Progressive buckling -- Half wavelength -- Sectionalized crushing force; Mechanical engineering -- Periodicals; Génie mécanique -- Périodiques; Mechanical engineering; Maschinenbau; Mechanik; Zeitschrift; Periodicals; 621.05
• DOI: 10.1016/j.ijmecsci.2016.01.033
• Languages: English
• ISSNs: 0020-7403

Abstract

Abstract: The progressive buckling behavior of a gradient grooved tube (GGT) designed for high temperature gas cooled reactor (HTR) is systematically studied in this paper. Based on the plastic hinge formation process, a sectionalized theoretical model is established to predict the quadratic upward trend of crushing force of GGT. The ordered and stable energy absorbing process of GGT is examined by low-speed axial impact using drop hammer test machine. The effect of proactive regulation parameters, including non-dimensional groove width W /( h 0 + h ), groove depth h 0 / h and half wavelength ( H + W − h ) / D h on buckling modes and force–displacement curve is determined by experiments and FE simulation. The non-dimensional groove width W /( h + h 0 ) is determined as π / 2 according to the geometry coordination of bending grooves. The non-dimensional groove depth h 0 / h influences local buckling behavior and the critical value 0.6 for regular bending has been determined by numerical simulation. The quadratic trend force–displacement curves of GGT can be actively controlled by ( H + W − h ) / Dh within a certain range less than 1.2. Free-fall impact experiments show that GGT has a better stability than perfect tube when used as an energy absorber to protect the graphite in HTR from slender control rod impact. Highlights: Gradient grooves are preset along the thin-walled circular tube to proactively regulate the collapse process. The sectionalized theory is developed to predict the quadratic upward crushing force. It is systemically studied the effects of non-dimensional defect parameters on buckling mode and crushing force of gradient grooved tube (GGT). It is demonstrated that GGT has a better stability than perfect tube when used as an absorber to protect the graphite in HTR from free-fall control rob.