温度-应力耦合作用下高密度聚乙烯板壳结构的导波频散特性

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中图分类号： TE88 文献标志码：A

Abstract：Ultrasonic guided waves are widelyused indefect identificationanddamage monitoringof high-densitypolyethylene（HDPE）plate/shellstructuresdue to their convenience and high eficiency.However，the temperature change and structural stress intheserviceenvironmentcan bring uncertaincoupling efects tothedispersion characteristicsof guided waves，limitingthereliabilityofguidedwavedetection technology.Inthispaper，basedontheFloquet-Blochperiodic boundary，thedispersionanalysismodelof HDPEplateandshellstructureisestablishedbyconsidering the initialstrainenergyof hyperelasticmaterialunder temperature-stress coupling.The influenceof temperature-stress couplingon modal wave structure，dispersioncurveand phase velocitychangeunderdiferentguided wave propagationdirections isstudied，and the accuracyofthemodelisverifiedbyexperiments.Thetemperatureandstressensitivityfactorsareintroducedtocharacterize the sensitivityof thephase velocityoftheguided wave mode totheambient temperatureandstressatdiferent frequencies. Theresults show thatthe inhomogeneous stress state intheguided wave propagation plane under uniform temperature variationsalters thedisplacement wave structuredistributionsof theLambandSHmodes，resulting inthedispersioncurvesof the tworepellingeachotheranddeviatingfromeachotherattheiroriginalintersection points.Thephasevelocitychangesarerelatedtothetemperature-stresscouplingconditions，frequencyand propagationdirection.Theeffectoftemperaturechangeon the phasevelocityof the waveguide modes is significantly greater thanthatof thestructural stress atthesame strain.The Lamb-AO mode with a frequency range higher than 1O kHz and the SH0 mode are both weakly sensitive to temperature changesand structural stress，andcanreducethe interference ofenvironmental factors onthe guided wave signal.Theresults explainthe coupling influence of diferentambient temperatures and stress onthe dispersion characteristicsof guided waves.

Keywords：HDPE plate/shellstructures；temperature-stresscoupling；Floquet-Bloch periodic boundary；dispersioncharac teristics； sensitivity analysis

高密度聚乙烯（HDPE）板壳结构具有很强的柔韧性、耐腐蚀性和可熔接性，被广泛应用于油田集输系统及城镇燃气输配等石油化工领域[1-2]。（剩余12704字）