简介：Basedonthetheoryofporousmedia,ageneralGurtinvariationalprinciplefortheinitialboundaryvalueproblemofdynamicalresponseoffluid-saturatedelasticporousmediaisdevelopedbyassuminginfinitesimaldeformationandincompressibleconstituentsofthesolidandfluidphase.Thefiniteelementformulationbasedonthisvariationalprincipleisalsoderived.Asthefunctionalofthevariationalprincipleisaspatialintegraloftheconvolutionformulation,thegeneralfiniteelementdiscretizationinspaceresultsinsymmetricaldifferential-integralequationsinthetimedomain.Insomesituations,thedifferential-integralequationscanbereducedtosym-metricaldifferentialequationsand,asanumericalexample,itisemployedtoanalyzethereflectionofone-dimensionallongitudinalwaveinafluid-saturatedporoussolid.Thenumericalresultscanprovidefurtherunderstandingofthewavepropagationinporousmedia.

简介：Basedontheporousmediatheoryandbytakingintoaccounttheeffectsoftheporefluidviscidity,energyexchangesduetotheadditionalthermalconductionandconvectionbetweensolidandfluidphases,amathematicalmodelforthedynamic-thermo-hydro-mechanicalcouplingofanon-localthermalequilibriumfluid-saturatedporousmedium,inwhichthetwoconstituentsareassumedtobeincompressibleandimmiscible,isestablishedundertheassumptionofsmalldeformationofthesolidphase,smallvelocityofthefluidphaseandsmalltemperaturechangesofthetwoconstituents.Themathematicalmodelofalocalthermalequilibriumfluid-saturatedporousmediumcanbeobtaineddirectlyfromtheaboveone.SeveralGurtin-typevariationalprinciples,especiallyHu-Washizutypevariationalprinciples,fortheinitialboundaryvalueproblemsofdynamicandquasi-staticresponsesarepresented.Itshouldbepointedoutthatthesevariationalprinciplescanbedegeneratedeasilyintothecaseofisothermalincompressiblefluid-saturatedelasticporousmedia,whichhavebeendiscussedpreviously.

简介：本文基于位移型Gurtin变分原理,对时间域进行离散时,采用具有非时间步参数的插值函数逼近广义节点位移,给出了一种新的计算弹性动力学初值问题的非时间步参数时间有限元法,这是一种无条件稳定的计算格式,通过算例,可知本文方法具有计算方法简便、实用和精度较高的特点。