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首页> 外文会议>国际断裂力学2009年会 >Non-Newtonian mechanics for small bodies
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Non-Newtonian mechanics for small bodies

机译：小型牛顿力学

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Interaction of mass and energy for small bodies acquires non-Newtonian behavior.Postulated is the existence of space/time to depend on the activation and deactivation of mass in relation to the absorption and dissipation of energy.Borne from the manifestation of the creation of matter is the concept that the intrinsic inhomogeneity gives rise to interfaces.Objects and events appear to exist as opposing poles with a transitional character across the interface.Simultaneity of direct-absorption and self-dissipation energy density,denoted,respectively,by W and D ,is further hypothesized to depend on the square of the velocity a2↑ that increases monotonically with time as indicated by the arrow head notation.The demise is that W=M↓ a2↑ and D=M↓ a2↑ where M↓is the activated mass associated with the direct-absorption energy density and M↓ is the deactivated mass associated with the self-dissipation energy density.The scheme also applies to large bodies. Scale segmentation justifies localizing attention to the energy source and/or sink as the region of damage.By specifying the life distribution for the different size/time scales,say tp/tn/tm/tm/tst,the rate at which damage is being done for each scale segment can be determined.The subscripts pi,na,mi,ma,and st designate,respectively,pico,nano,micro,macro,and structure.The actual time distribution in years may be 1.5/2.5/3.5/5.5/7.0 for a total of 20 years.The time of arrow in years will depend on the problem definition.The direction of pico→ nano→micro→macro→struc.corresponds to progressive damage while other choices can also be considered.The energy density function can be found without a knowledge of the entire field quantities such as stress and strain. Demonstrated will be a picoano/micro/macro fatigue cracking model of a 2024-T3 aluminum panel.Only the undamaged material properties are employed.Time degradation of the picoano/micro/macro material structure is derived by using nine scale transitional physical parameters:three for the picoano range (μ*pia,σ*pia,d*pia),three for the na-no/micro range (μ*na/mi,σ*na/mi,d*na/mi) and three for the micro/macro range (μ*mi/ma,σ*mi/ma,d*mi/ma).Only the ratios of twosuccessive scale sensitive parameters need to be specified.The time dependent physical parameters at the lower scale are implicit and needed only for analytical continuation. More precisely,the transitional character of picocracks,nanocracks,microcracks and macrocracks are determined from the specified life expectancy of time arrow according to pico→nano→micro→macro with the respective singularity strength of λ given by 1.25/1.00/0.75/0.50.Note that λ=0.5 corresponds to the inverse square root r-0 5 in fracture mechanics with r being the distance from the macro-crack tip.The micro-crack,nanocrack and pico-crack tips are assigned with the singularities r-0 75,r-1 00,and r-1 25,respectively.The time dependent material degradation process over the total life span is enforced such that the energy dissipated in damaging the internal material structure at each scale range can be matched with that caused by loading.Material inhomogeneities at the different scales are thus compensated by the inhomogeneous reinforcements at the same different scales.In this way,the energy release rate at each scale would be relatively homogeneous and controlled.
机译：小物体的质量与能量相互作用获得了非牛顿行为。假设存在空间/时间取决于与能量吸收和耗散有关的质量激活和失活。是内在的不均匀性引起界面的概念。对象和事件似乎以相对的极点存在，并在界面上具有过渡特性。直接吸收和自耗散能量密度的同时性，分别由W和D表示，进一步假设其取决于速度a2↑的平方，该速度随时间如箭头箭头所示单调增加。消逝是W = M↓a2↑和D = M↓a2↑其中M↓是激活质量与直接吸收能量密度相关的M↓是与自耗散能量密度相关的失活质量，该方案也适用于大型物体。比例尺分段可以将注意力集中在作为损坏区域的能源和/或汇上。通过指定不同尺寸/时间比例尺的寿命分布，例如tp / tn / tm / tm / tst，确定损坏的速率下标pi，na，mi，ma和st分别指定pico，nano，micro，macro和structure。下一年的实际时间分布可能为1.5 / 2.5 / 3.5 / 5.5 / 7.0，共20年。箭头的时间取决于问题的定义.pico→nano→micro→macro→struc的方向对应于渐进式损坏，也可以考虑其他选择。在不了解整个场量（例如应力和应变）的情况下，可以找到密度函数。演示了2024-T3铝板的皮/纳米/微/宏观疲劳开裂模型，仅采用了未损坏的材料性能，使用九尺度过渡得出了皮/纳米/微/宏观材料结构的时间退化物理参数：3个用于微微/纳米范围（μ* pi / na，σ* pi / na，d * pi / na），三个用于无/微范围（μ* na / mi，σ* na / mi，d * na / mi）和三个用于微/微范围（μ* mi / ma，σ* mi / ma，d * mi / ma），仅需要指定两个连续的比例敏感参数的比率。较低级别的时间相关物理参数是隐式的，仅在分析连续性时才需要。更精确地，根据pico→nano→micro→宏，根据时间箭头的指定寿命，确定皮裂纹，纳米裂纹，微裂纹和大裂纹的过渡特性，其中奇异强度λ分别为1.25 / 1.00 / 0.75 / 0.50。请注意，λ= 0.5对应于断裂力学中的平方根r-0 5，其中r是距大裂纹尖端的距离。微裂纹，纳米裂纹和微裂纹尖端的奇点为r-0 75 ，r-1 00和r-1 25分别进行。在整个寿命周期内都执行与时间有关的材料降解过程，以使在每个尺度范围内破坏内部材料结构所耗散的能量可以与载荷所造成的能量相匹配。因此，在不同尺度上的材料不均匀性可以通过在相同尺度上的不均匀增强材料得到补偿。这样，每个尺度上的能量释放率将相对均匀并受到控制。

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