摘要:
基于铝蜂窝表观密度、质量、平台强度、异面弹性模量、压缩率、吸能量6个基本力学量,建立了正
六边形铝蜂窝等效前后胞元厚跨比(胞壁厚度与跨度的比)间的映射关系,得到相同厚跨比蜂窝结构具有相同
的力学属性与吸能特性。采用以大换小的扩胞途径,保持胞元厚跨比不变,通过改变蜂窝胞元结构几何参数,
提出了将致密孔格稀疏化的蜂窝扩胞等效分析流程,实现了致密蜂窝数值模拟时单元规模与计算时间的有
效减缩。基于显式有限元方法,建立了8种等间距扩胞铝蜂窝求解模型,结果验证了扩胞等效方法的可行性。
等效前后计算效率的对比分析显示了扩胞方法的高效性。但在异面方向尺度与胞元跨度相近时,扩胞等效方
法受到一定的局限。
关键词:
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固体力学 /
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等效方法 /
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扩胞 /
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铝蜂窝 /
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异面压缩
Abstract:
Basedonthesixbasicparametersincludingapparentdensity,mass,plateauload,out-ofplaneelasticmodulus,
compressionratioandenergyabsorption,themappingrelationsweredeveloped
betweenthethickness-lengthratiosofthehexagonalaluminumhoneycombcellsbeforeandaftermagnification.
Thedevelopedmappingrelationsdisplaythatthecellularstructureswiththesamethickness-
lengthratioshavethesamemechanicalandenergy-absorbingproperties.Bymagnifyingthecell
geometricconfigurationsinlengthbutkeepingthesamethickness-lengthratiosatthesametimes,a
newanalysisprocesswasputforwardfortheequivalentmagnificationofthealuminum honeycomb
cellsfromcompactnesstosparseness.Basedontheaboveanalysisprocess,thetimecostinthenumericalsimulationforthehigh-
densitycellularstructureswasdecreasedbyreducingthecellnumbers.
Subsequently,eightnumericalmodelsat1-8timesmagnificationofthesamealuminumhoneycomb
cellwerebuiltonthebasisoftheexplicitfiniteelementmethodandthesimulatedresultsbythem
confirmedthevalidityoftheequivalentmethoddeveloped.Comparisonofthecomputedtimebefore
andaftermagnificationshowsthehighefficiencyoftheequivalentmethod.Butwhenthetotalsizein
theout-of-planedirectionisapproximatetothecelllength,theequivalentmethodislimited.
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