Articles techniques et présentations

扬声器的失真问题一直受电声业界的关注，尤其是谐波失真，它是影响扬声器重放声音音质的主要因素之一。 本文提出了一种基于 COMSOL Multiphysics® 软件预测扬声器谐波失真的仿真分析方法。该方法需建立包括磁场、振动系统和声场等多个物理场的扬声器的全模型，给扬声器加载一单频电压信号，用瞬态分析的方法可求解得到该频率激励下的扬声器的多个重要物理量随时间的变化函数，如流经音圈的电流I(t)、音圈的受力F(t)、振动系统表面上任意点的位移x(t)，以及声场中任意点的声压P(t)等。给扬声器加载一个时间长度为0.1s的单频电压信号，仿真分析所得的防尘帽顶点的位移曲线 ... En savoir plus

The maintenance plan or rush-to-repair of a subsea pipeline for oil transport may result in the shutdown of the line, in other words, may stop the flow of fluid. During the shutdown, the temperature of the oil tends to decrease continuously, and the heavy molecules tend to crystallize ... En savoir plus

The determination of the modes of vibration of Functionally Graded-Metal-Ceramic Composite plates is important in practice in order to prevent undesired resonances in structural components. This paper describes the application of COMSOL Multiphysics® software for the determination of the ... En savoir plus

Energy piles, i.e. heat exchangers located within the foundation piles of buildings, are used for heating of cooling purposes. Although the absolute values of deformations and temperature gradients are low or moderate, the entire setting can be influenced by thermo-hydro-mechanical ... En savoir plus

In this paper a multiphysics approach to study the optical properties of integrated waveguides influenced by thermal and mechanical stress is presented. The heating and pressure effects are evaluated by means the Heat Transfer and Structural Mechanics modules respectively. Finally, the ... En savoir plus

This paper describes the Virtual Prototype of a Dielectric Window or High Power Microwave Vacuum Tubes and Linear Accelerators. Design formulas are provided and Computer Aided Design techniques based on COMSOL Multiphysics® software are proposed. The virtual prototype considers the ... En savoir plus

Absorber tubes are one of the most critical components of parabolic trough Concentrated Solar Plants, which is very likely get damaged such as crack and mass loss. Therefore, the monitoring of their structural health via Non-Destructive Testing (NDT) techniques is regarded as essential ... En savoir plus

COMSOL Multiphysics® software is used to model the field joint application process on carbon steel pipelines for deep sea crude oil transportation, taking into account not only heat transfer, cure kinetics, and crystallization, but also thermal, cure and crystallization shrinkage and the ... En savoir plus

The use of high-resolution topography in the finite element model demonstrates that deformation from a shallow pressure source can be dramatically affected by overlying relief, not only in magnitude, but also in azimuth. This result is significant as it allows traditionally anomalous ... En savoir plus

As any other modelling of a physical behavior, the numerical simulation of the mechanical response of an adaptive secondary mirror requires that the results match the experimental data. Such an agreement was recently demonstrated for the local mirror stiffness of the LBT and VLT ... En savoir plus