为考察轴力对梁高频振动的影响,建立了轴力作用下梁的能量辐射传递模型。针对具有恒定轴力作用的Euler-Bernoulli梁,引入受轴力影响的波数和群速度,建立能量密度控制方程,推导轴力作用下梁的能量密度和能量强度的核函数。实源强度由导...为考察轴力对梁高频振动的影响,建立了轴力作用下梁的能量辐射传递模型。针对具有恒定轴力作用的Euler-Bernoulli梁,引入受轴力影响的波数和群速度,建立能量密度控制方程,推导轴力作用下梁的能量密度和能量强度的核函数。实源强度由导纳法计算得到的输入功率表示,虚源强度通过边界能量平衡方程确定,根据惠更斯原理,梁的能量响应由实源产生的直接场与虚源产生的反射场线性叠加得到。通过将能量辐射传递法(energy radiative transfer model,RETM)获得的结果与波传播法解析解进行比较,分析了轴力作用下无限结构导纳的适用性,验证所提RETM的正确性,同时分析了轴力对梁能量响应的影响。展开更多
该研究的目的是将能量辐射传递法(radiative energy transfer method,RETM)推广到功能梯度板模型中,以预测结构的高频振动响应。基于一阶剪切变形理论推导了功能梯度板的振动控制方程,获得了波传播特性参数。在该方法中,结构内部的能量...该研究的目的是将能量辐射传递法(radiative energy transfer method,RETM)推广到功能梯度板模型中,以预测结构的高频振动响应。基于一阶剪切变形理论推导了功能梯度板的振动控制方程,获得了波传播特性参数。在该方法中,结构内部的能量响应由激励产生的直接场与边界虚源产生的反射场叠加得到。在临界频率以下,能量响应由一种传播波控制;而在临界频率以上,由三种传播波控制。数值算例结果与模态叠加法和功率流分析进行了对比,验证了RETM在计算不同物理参数下功能梯度板高频振动响应的准确性。研究了不同厚度下剪切变形和转动惯量对能量响应的影响,讨论了材料梯度因子、结构阻尼和激励频率对高频振动能量的影响。结果表明,材料梯度因子的变化会导致结构波传播特性和能量分布特征的变化,越大能量的衰减速度越快,衰减幅度越大。展开更多
该研究的目的是将能量辐射传递法(radiative energy transfer method,RETM)推广到三明治耦合板模型中。推导了三明治板的振动控制方程,获得结构的波传播特性参数。基于波法推导了三明治耦合板的能量传递系数。根据能量密度控制方程,得...该研究的目的是将能量辐射传递法(radiative energy transfer method,RETM)推广到三明治耦合板模型中。推导了三明治板的振动控制方程,获得结构的波传播特性参数。基于波法推导了三明治耦合板的能量传递系数。根据能量密度控制方程,得到能量密度和功率流强度的核函数。根据惠更斯原理,结构内部的能量可由实源辐射的直接场能量与边界虚源的反射场能量叠加得到。求解第二类Fredholm积分方程获得边界虚源的强度。数值算例结果与模态叠加和功率流分析(power flow analysis,PFA)对比,验证了所建模型的正确性和准确性。对L型耦合三明治板求解,获得其能量密度和功率流分布特征。展开更多
Two bi-part combined models containing reaction equilibrium thermodynamic model and an equation of state(EoS)including cubic plus association(CPA)or modified Soave-Redlich-Kwong(SRK),were employed to correlate H_(2)S ...Two bi-part combined models containing reaction equilibrium thermodynamic model and an equation of state(EoS)including cubic plus association(CPA)or modified Soave-Redlich-Kwong(SRK),were employed to correlate H_(2)S solubility in ionic liquids[emim][Lac],[bmim][Ac]and[emim][Pro].RETM and CPA/mSRK are responsible for chemical and phase equilibria calculations,respectively.The RETM defines a complex formation reaction between an H_(2)S and two IL molecules into the liquid phase so that a complex in the form of H_(2)S(IL)_(2)is probable to produce.On the other side,CPA/mSRK EoSs perform phase equilibria computations to find pressure and vapor phase concentrations.In the case of CPA,both of H_(2)S and the ionic liquids were considered as self-associating components which pursue 4 C and 2 B schemes,respectively.This model computes the pure IL parameters using experimental density data.In this work,critical properties were estimated through the modified Lydersen-Joback-Reid method,Eotvos and Guggenheim relations.Afterward,the binary systems were investigated by applying RETM.CPA presents average absolute deviations(AADs)equal to 2.41%,13.42%and 3.52%for[emim][Lac],[bmim][Ac],and[emim][Pro],respectively.Moreover,the AADs obtained by mSRK are 3.75%,5.07%,and 6.06%,respectively.As it is evident from the results,the combination of RETM with both CPA and m SRK EoSs will result in good correlation accuracy.展开更多
文摘为考察轴力对梁高频振动的影响,建立了轴力作用下梁的能量辐射传递模型。针对具有恒定轴力作用的Euler-Bernoulli梁,引入受轴力影响的波数和群速度,建立能量密度控制方程,推导轴力作用下梁的能量密度和能量强度的核函数。实源强度由导纳法计算得到的输入功率表示,虚源强度通过边界能量平衡方程确定,根据惠更斯原理,梁的能量响应由实源产生的直接场与虚源产生的反射场线性叠加得到。通过将能量辐射传递法(energy radiative transfer model,RETM)获得的结果与波传播法解析解进行比较,分析了轴力作用下无限结构导纳的适用性,验证所提RETM的正确性,同时分析了轴力对梁能量响应的影响。
文摘该研究的目的是将能量辐射传递法(radiative energy transfer method,RETM)推广到功能梯度板模型中,以预测结构的高频振动响应。基于一阶剪切变形理论推导了功能梯度板的振动控制方程,获得了波传播特性参数。在该方法中,结构内部的能量响应由激励产生的直接场与边界虚源产生的反射场叠加得到。在临界频率以下,能量响应由一种传播波控制;而在临界频率以上,由三种传播波控制。数值算例结果与模态叠加法和功率流分析进行了对比,验证了RETM在计算不同物理参数下功能梯度板高频振动响应的准确性。研究了不同厚度下剪切变形和转动惯量对能量响应的影响,讨论了材料梯度因子、结构阻尼和激励频率对高频振动能量的影响。结果表明,材料梯度因子的变化会导致结构波传播特性和能量分布特征的变化,越大能量的衰减速度越快,衰减幅度越大。
文摘该研究的目的是将能量辐射传递法(radiative energy transfer method,RETM)推广到三明治耦合板模型中。推导了三明治板的振动控制方程,获得结构的波传播特性参数。基于波法推导了三明治耦合板的能量传递系数。根据能量密度控制方程,得到能量密度和功率流强度的核函数。根据惠更斯原理,结构内部的能量可由实源辐射的直接场能量与边界虚源的反射场能量叠加得到。求解第二类Fredholm积分方程获得边界虚源的强度。数值算例结果与模态叠加和功率流分析(power flow analysis,PFA)对比,验证了所建模型的正确性和准确性。对L型耦合三明治板求解,获得其能量密度和功率流分布特征。
文摘Two bi-part combined models containing reaction equilibrium thermodynamic model and an equation of state(EoS)including cubic plus association(CPA)or modified Soave-Redlich-Kwong(SRK),were employed to correlate H_(2)S solubility in ionic liquids[emim][Lac],[bmim][Ac]and[emim][Pro].RETM and CPA/mSRK are responsible for chemical and phase equilibria calculations,respectively.The RETM defines a complex formation reaction between an H_(2)S and two IL molecules into the liquid phase so that a complex in the form of H_(2)S(IL)_(2)is probable to produce.On the other side,CPA/mSRK EoSs perform phase equilibria computations to find pressure and vapor phase concentrations.In the case of CPA,both of H_(2)S and the ionic liquids were considered as self-associating components which pursue 4 C and 2 B schemes,respectively.This model computes the pure IL parameters using experimental density data.In this work,critical properties were estimated through the modified Lydersen-Joback-Reid method,Eotvos and Guggenheim relations.Afterward,the binary systems were investigated by applying RETM.CPA presents average absolute deviations(AADs)equal to 2.41%,13.42%and 3.52%for[emim][Lac],[bmim][Ac],and[emim][Pro],respectively.Moreover,the AADs obtained by mSRK are 3.75%,5.07%,and 6.06%,respectively.As it is evident from the results,the combination of RETM with both CPA and m SRK EoSs will result in good correlation accuracy.