近年来,嵌入式声学黑洞(acoustic black holes,ABH)以其优异的性能,在结构减振降噪、声波调控、能量回收等领域展示了广阔的应用前景,但其局部结构强度弱化会影响其工程实用性。提出一种碟形声学黑洞(dish-shaped acoustic black hole,D...近年来,嵌入式声学黑洞(acoustic black holes,ABH)以其优异的性能,在结构减振降噪、声波调控、能量回收等领域展示了广阔的应用前景,但其局部结构强度弱化会影响其工程实用性。提出一种碟形声学黑洞(dish-shaped acoustic black hole,DABH)结构,将其附加在主体结构上,以实现对主体结构的宽频减振。在Rayleigh-Ritz法框架下,选择高斯函数作为基函数,根据声学黑洞板的形状确定基函数的分布,避免质量和刚度矩阵的奇异化,建立了其耦合系统半解析模型。通过与有限元模态分析结果的对比,验证了半解析建模方法的正确性。研究了碟形声学黑洞结构参数以及连接位置对主体结构振动响应特性的影响规律,分析了碟形声学黑洞的ABH效应以及与主体结构的耦合效应,揭示了其宽频调谐减振的机理,为拓展声学黑洞在宽频结构振动控制上的应用提供了新的思路。展开更多
基于四次方程的三角解法,给出了动态Kerr-Newman de Sitter黑洞的视界位置。引入局部热平衡的概念,运用改进后的brick- wall模型——薄膜模型,研究了此黑洞的熵。当把黑洞视界和宇宙视界附近一薄层物质场的熵分别看作各自视界的熵,并选...基于四次方程的三角解法,给出了动态Kerr-Newman de Sitter黑洞的视界位置。引入局部热平衡的概念,运用改进后的brick- wall模型——薄膜模型,研究了此黑洞的熵。当把黑洞视界和宇宙视界附近一薄层物质场的熵分别看作各自视界的熵,并选择与静态、稳态黑洞相同的截断因子时,计算结果与面积定理完全一致。展开更多
A method with which one can calculate the entropy of a non-stationary and non-spherically symmetric black hole is suggested. This method is universal to every kind of black holes. By means of thin film model, the entr...A method with which one can calculate the entropy of a non-stationary and non-spherically symmetric black hole is suggested. This method is universal to every kind of black holes. By means of thin film model, the entropy density at every point of the event horizon is calculated first, then the total entropy is obtained through integration.展开更多
The generalized Teukolsky- type mater equation is discussed. The result shows that the non- stationary black holes should have some new quantum effects which are unknown as yet.
文摘近年来,嵌入式声学黑洞(acoustic black holes,ABH)以其优异的性能,在结构减振降噪、声波调控、能量回收等领域展示了广阔的应用前景,但其局部结构强度弱化会影响其工程实用性。提出一种碟形声学黑洞(dish-shaped acoustic black hole,DABH)结构,将其附加在主体结构上,以实现对主体结构的宽频减振。在Rayleigh-Ritz法框架下,选择高斯函数作为基函数,根据声学黑洞板的形状确定基函数的分布,避免质量和刚度矩阵的奇异化,建立了其耦合系统半解析模型。通过与有限元模态分析结果的对比,验证了半解析建模方法的正确性。研究了碟形声学黑洞结构参数以及连接位置对主体结构振动响应特性的影响规律,分析了碟形声学黑洞的ABH效应以及与主体结构的耦合效应,揭示了其宽频调谐减振的机理,为拓展声学黑洞在宽频结构振动控制上的应用提供了新的思路。
文摘基于四次方程的三角解法,给出了动态Kerr-Newman de Sitter黑洞的视界位置。引入局部热平衡的概念,运用改进后的brick- wall模型——薄膜模型,研究了此黑洞的熵。当把黑洞视界和宇宙视界附近一薄层物质场的熵分别看作各自视界的熵,并选择与静态、稳态黑洞相同的截断因子时,计算结果与面积定理完全一致。
文摘A method with which one can calculate the entropy of a non-stationary and non-spherically symmetric black hole is suggested. This method is universal to every kind of black holes. By means of thin film model, the entropy density at every point of the event horizon is calculated first, then the total entropy is obtained through integration.
文摘The generalized Teukolsky- type mater equation is discussed. The result shows that the non- stationary black holes should have some new quantum effects which are unknown as yet.