We study a new class of elliptic variational-hemivariational inequalities arising in the modelling of contact problems for elastic ideally locking materials. The contact is described by the Signorini unilateral contac...We study a new class of elliptic variational-hemivariational inequalities arising in the modelling of contact problems for elastic ideally locking materials. The contact is described by the Signorini unilateral contact condition and the friction is modelled by the nonmonotone multivalued subdifferential condition which depends on the slip. The problem is governed by a nonlinear elasticity operator, the subdifferential of the indicator function of a convex set which describes the locking constraints and a nonconvex locally Lipschitz friction potential. The result on existence and uniqueness of solution to the inequality is shown. The proof is based on a surjectivity result for maximal monotone and pseudomonotone operators combined with the application of the Banach contraction principle.展开更多
针对运载火箭共底贮箱独特的密封锁底焊缝承压结构开展搅拌摩擦焊工艺技术研究,采用基于锁底结构搅拌工具设计的无匙孔回抽全焊透工艺技术,探究搅拌针长度、前进侧位置、坡口尺寸对4 mm 2A14铝合金锁底焊缝强度的影响。经过焊接试验验证...针对运载火箭共底贮箱独特的密封锁底焊缝承压结构开展搅拌摩擦焊工艺技术研究,采用基于锁底结构搅拌工具设计的无匙孔回抽全焊透工艺技术,探究搅拌针长度、前进侧位置、坡口尺寸对4 mm 2A14铝合金锁底焊缝强度的影响。经过焊接试验验证,针长度为-0.1~0.3 mm,前进侧位于锁底侧,焊接坡口设为0.5mm时为最优焊接工艺参数,焊缝强度高于熔焊焊缝强度。对锁底焊缝引钩(HOOK)缺陷进行研究,抑制了HOOK的产生,实现了搅拌摩擦焊方法在运载火箭承压锁底结构的首次应用与飞行验证,提高了焊接效率和质量,并实现整箱减重。展开更多
基金supported by the National Science Center of Poland under the Maestro 3 Project No.DEC-2012/06/A/ST1/00262the project Polonium“Mathematical and Numerical Analysis for Contact Problems with Friction”2014/15 between the Jagiellonian University and Universitde Perpignan Via Domitia
文摘We study a new class of elliptic variational-hemivariational inequalities arising in the modelling of contact problems for elastic ideally locking materials. The contact is described by the Signorini unilateral contact condition and the friction is modelled by the nonmonotone multivalued subdifferential condition which depends on the slip. The problem is governed by a nonlinear elasticity operator, the subdifferential of the indicator function of a convex set which describes the locking constraints and a nonconvex locally Lipschitz friction potential. The result on existence and uniqueness of solution to the inequality is shown. The proof is based on a surjectivity result for maximal monotone and pseudomonotone operators combined with the application of the Banach contraction principle.
文摘针对运载火箭共底贮箱独特的密封锁底焊缝承压结构开展搅拌摩擦焊工艺技术研究,采用基于锁底结构搅拌工具设计的无匙孔回抽全焊透工艺技术,探究搅拌针长度、前进侧位置、坡口尺寸对4 mm 2A14铝合金锁底焊缝强度的影响。经过焊接试验验证,针长度为-0.1~0.3 mm,前进侧位于锁底侧,焊接坡口设为0.5mm时为最优焊接工艺参数,焊缝强度高于熔焊焊缝强度。对锁底焊缝引钩(HOOK)缺陷进行研究,抑制了HOOK的产生,实现了搅拌摩擦焊方法在运载火箭承压锁底结构的首次应用与飞行验证,提高了焊接效率和质量,并实现整箱减重。
