排序方式: 共有10条查询结果,搜索用时 15 毫秒
1
1.
The present investigation is aimed at studying the deformation in thermo-microstretch elastic medium occuping the region y ? 0 with a stable internal heat source. A nonviscous fluid layer of height h is overlying the thermoelastic medium and a mechanical source of constant magnitude is applied along the fluid/solid interface. The normal mode analysis is used to obtain the exact expressions for displacement components, force stress, and temperature distribution. The numerical results are given and presented graphically for the Green–Lindsay theory of thermoelasticity. The variations of the considered variables through the horizontal distance are illustrated graphically. Comparisons are made with the results in the presence and absence of microstretch and microrotation parameters. 相似文献
2.
Regular wave impact onto an elastic plate 总被引:1,自引:0,他引:1
A computational analysis of an elastic plate dropped against regular long waves is presented. The problem is considered within
the linear potential-flow theory. The liquid flow is two-dimensional and the plate is modelled by an Euler beam. The analysis
is based on the normal-mode method with hydroelastic behavior of the plate being of main interest. Different impact conditions
are considered to study the dependence of the total energy of the plate–liquid system on impact geometry and plate properties.
The contributions of kinetic and potential energies to the total energy are analyzed. It is shown that the kinetic part of
the system energy is small at the instant of time when bending stresses in the beam approach their maximum values. Estimations
of both the total energy and the maximum of bending stresses are presented. Most of the calculations are performed for the
conditions of experiments carried out in MARINTEK. A range of the problem parameters is also considered, to reveal peculiarities
of the unsteady interaction between a falling elastic plate and surface waves. 相似文献
3.
4.
为提高宽带简正波本征值的计算效率,汉密尔顿方法通过公式变换抵消频率项,将宽带简正波本征值的计算由频率、本征值实部和虚部的三维寻根降低至本征值实部和虚部的二维寻根,可以一次性求解单号简正波所有频率对应的简正波本征值。在已有工作的基础上优化和完善了汉密尔顿宽带简正波本征值算法,并加入并行计算方法进一步提高计算效率。以简正波模型KRAKENC作为对比,通过若干数值算例验证了该算法对于宽带简正波本征值的计算精度和计算效率。数值仿真结果显示,在保证宽带简正波本征值计算精度的前提下,该方法的计算效率相对KRAKENC有着明显的优势;加入并行算法后,该方法的计算效率得到大幅提高。 相似文献
5.
6.
浅海环境中,目标回波受到入射和散射双向过程的信道多途影响,具有复杂的多途结构。基于相控垂直阵的单模发射技术能激发出指定的单个简正波声场,可以降低海底混响干扰,简化目标回波多途结构,为主动探测提供了一种有效手段。在信道中点声源目标回波模型基础上,采用简正波本征函数加权研究了单模声场入射下球形目标散射问题,建立了浅海单模入射声场目标回波预报模型,并利用模型对刚性球回波进行了数值计算。结果表明:总声源级相同条件下,单模发射声场与传统的点声源发射声场相比具有一定的阵发射增益,目标回波具有较高的声压级;单模入射能够消除单程多途的影响,回波结构相对简单,有利于目标的探测和识别。 相似文献
7.
浅海主动探测时,海底混响是目标回波的主要背景干扰,信混比影响主动声纳的性能.混响和目标回波都属于海洋中的散射问题,利用简正波方法,结合平面波散射函数建立了浅海远程信混比预报模型,实现了不同环境参数下信混比的量化分析.仿真比较了不同信号形式、频率以及不同海底底质下的刚性球信混比曲线,从理论上分析了回波随距离的振荡现象.结果表明:用无指向性的声源探测目标时,信混比较低,探测较为困难;宽带信号照射下目标回波更加平稳;简正波之间的干涉导致回波随距离发生振荡,频率越高,干涉结构越复杂;在硬海底环境中信混比相对较小且目标回波振荡剧烈. 相似文献
8.
一、引言RC模拟滤波器,是一种低通滤波器。虽然人们对它并不陌生,但把它用于工业控制机的输入部分,并且合理地选用它,也并不是一件容易的事。随着计算机技术的发展,工业用数据采集系统得到了广泛的应用。由于它的输入讯号来自于生产过程中的各种测量仪表,而这些仪表又多安装在充满各种电磁干扰的环境中, 相似文献
9.
过去设海底是一种连续的液态介质,由简正波声场的本征值(极点)方程解出其中的衰减系数,该衰减系数是由海底上的平面声波的反射系数和水文条件来表出.这样的结果是唯象结果,看不出海底沉积物的基本参数对它的影响.现在设海底是一种松散的颗粒介质(沙(泥)质沉积物),由声场的本征值引入本征声线的概念,用射线声学的方法导出了简正波的衰减系数,借助于松散颗粒介质上的平面声波反射系数的表式使该衰减系数与海底沉积物的基本参数联系起来,克服了过去唯象结果的不足,但与过去的唯象结果互相沟通、互相补充和互相佐证. 相似文献
10.
U. Satya Sainadh 《Journal of Modern Optics》2019,66(5):494-501
We consider an optical and mechanical mode interacting through both linear and quadratic dispersive couplings in a general cavity-optomechanical set-up. The parity and strength of an intrinsic quadratic optomechanical coupling (QOC) provides an opportunity to control the optomechanical (OM) interaction. We quantify this interaction by studying normal-mode splitting (NMS) as a function of the QOC's strength. The proposed scheme exhibits NMS features equivalent to a hybrid-OM system containing either an optical parametric amplifier or a Kerr medium. Such a system in reality could offer an alternative platform for devising state-of-art quantum devices with requiring no extra degrees-of-freedom as in hybrid-OM systems. 相似文献
1