ACOUSTIC REFLECTION FROM A BAFFLED ELASTIC/PIEZOELECTRIC PLATE

来源 :Acta Mechanica Solida Sinica | 被引量 : 0次 | 上传用户:ujjih
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
A finite difference/boundary integral procedure to determine the acoustic reflected pressurefrom a fluid-loaded bi-laminated plate is described.The bi-laminate is composed of a piezoelectric layer andan elastic layer in contact with the fluid,and is held by an acoustically hard baffle.In the numerical model,the fluid pressure at fluid/solid interface is replaced by a continuum of point sources weighted by the normalacceleration of the elastic plate,and the governing equation system is solved in the solid domain.With thenormal acceleration found,the reflected pressure in the fluid is determined by an integral expression involv-ing the Green’s function.It is demonstrated that an appropriate applied voltage potential across the piezoelec-tric layer has the effect of cancelling either the reflected or scattered pressure of the plate at any chosen fieldpoints in the fluid. A finite difference / boundary integral procedure to determine the acoustic reflected pressure from a fluid-loaded bi-laminated plate is described. The bi-laminate is composed of a piezoelectric layer and an elastic layer in contact with the fluid, and is held by an acoustically hard baffle.In the numerical model, the fluid pressure at fluid / solid interface is replaced by a continuum of point sources weighted by the normalacceleration of the elastic plate, and the governing equation system is solved in the solid domain .With thenormal acceleration found, the reflected pressure in the fluid is determined by an integral expression involv-ing the Green’s function. It is said that an appropriate applied voltage potential across the piezoelec-tric layer has the effect of canceling either the reflected or scattered pressure of the plate at any chosen. fieldpoints in the fluid.
其他文献
本文对乌毛蕨贯众进行资源分布、植物形态、药材性状、显微特征及理化鉴别的研究 This paper studies the distribution of resources, plant morphology, medicinal proper
茄子根(Solanum melongena)能活血止痛,利湿消肿,民间用于治疗齿痛,风湿性关节炎及冻疮等病症,笔者对其活血止痛作用进行了初步实验研究,现报告如下。 Solanum melongena c
对本县18所乡卫生院40名院长现状进行了调查。通过调查分析表明:院长队伍年龄结构不合理;高层次学历和中、高技术职务人员较少;对本职工作不满意和无所谓者占62.5%;影响院长工作的因素较多,如为爱人子女找工作、住房困难和负责管理责任等。为此各级领导要把培养院长作为一项战略任务,提高他们的管理素质;要健全院长竞争机制;加强院长的自身修养,提高系统管理艺术和组织管理能力;摆正工作主次关系,纠正重业务轻管
以大黄素为标样,以5%NaOH-2%NH4OH为显色剂,用紫外-可见分光光度法在510nm处测定了北京、天津等7厂家石斛夜光丸中游离、结合和总蒽醌的含量,测定最大变异系数为3.79%,加样回收率为100.4%。 Using emodin as a st
灌胃给予L615白血病患鼠狼毒大戟水提物3.0g/kg(相当生药)7d,小鼠T淋巴白血病细胞增殖受到了较强地抑制(P<0.02),显著增加了由于L615白血病细胞攻击所致的肝中谷胱甘肽过氧化酶(GSH-Px)和超氧化物歧化酶活力(SOD)下降(P<0.01,P<0.001)。但
对四神茶剂挥发油用正交试验法探讨其β-CD包合条件,结果以β-CD与挥发油4:0.75、45℃、2h最佳。经GC分析,证明包合前后挥发油主要成分基本一致。经差示扫描量热分析法和X──射
几年前,全国劳模李素丽说过一句话:“用力去做,只能做到称职;用心去做,才能做到优秀。”这话今天回味起来仍很值得我们深思,同样是在工作,在尽己所能地努力,但一个是用力,一个是用心,二
正睡的迷迷糊糊,突然就有电话铃声让你如“炸尸”般直挺挺坐将起来,聆听着心脏咚咚的跳声,揣测着那是何人竟挑了子午时分来扰人清梦——通常这种情况不是骚扰电话就是最亲的
在我国服务业整体较为弱小的现阶段,服务贸易对外开放,有提升国内服务业的积极作用,也有挤压国内服务业的负面影响。如何趋利避害、为我所用、因势利导、统筹协调,正确处理开放、扩大服务贸易与发展壮大国内服务业的矛盾,不仅在近期已经提上议事日程,从长期看,更将成为影响全局的战略问题。    一、扩大服务贸易与壮大国内服务业不协调的主要表现    (一)货物贸易和服务贸易发展势头反差强烈,且扭转难度很大  在
本文通过总结分析多媒体技术在初中语文课堂中使用的现状,从多媒体在课堂中的运用也逐步暴露出其缺点和操作中容易步入的误区出发,对问题及原因的剖析、问题解决策略的选择、