技術情報とプレゼンテーション

基于 Level-Set 界面跟踪方法建立了激光熔覆过程的三维瞬态数值模型，研究了瞬态熔化和凝固过程中传热传质的演化规律。该模型使用 Level-Set 方法跟踪熔池气/液界面，采用焓－多孔度（enthalpy-porosity）方法得到了固/液界面之间的糊状区，并考虑了质量添加、材料熔化/凝固、热毛细效应（Marangoni效应）、浮力效应、活性元素质量传输等对熔池流动和界面的影响。通过该模型，具体分析了质量添加、力和界面平衡条件对熔池气/液界面的影响，以及由熔池温度/浓度分布引起的热毛细效应、金属材料的熔/凝过程和熔池流动形式对熔池固/液界面的影响。结果表明 ... 詳細を見る

De Laval nozzles are used in supersonic aerodynamical tubes and engines. They are also employed for the production of cold gas jets to be used in chemical reactions studies. Recently, cold gas jets have been proposed of In-Gas Laser ionization Spectroscopy (IGLIS) The nozzle has a ... 詳細を見る

由于异种金属的热物理性能存在较大差异，在焊接过程中极易形成金属间化合物，这给两种材料的焊接造成了一定的困难。因此，针对钢/铝异种金属焊接存在的难点，建立了基于COMSOL软件的激光-TIG复合热源焊三维瞬态熔池数值分析模型。利用所建模型对不同焊接条件下的激光-TIG复合热源焊熔池形貌和温度场进行模拟计算，分别探讨了激光功率、电弧电流及焊接速度对复合焊焊接温度场的影响规律。 詳細を見る

Ultrasonic sensors are commonly used for a wide variety of non-contact presence, proximity or distance measuring applications in industry, especially the automotive branch. This paper shows how the radiation properties of bending-type ultrasonic transducers with rotational symmetry ... 詳細を見る

Metamaterials are a new class of artificial materials, which possess various unusual properties. One of these properties is a negative index of refraction produced by setting both the dielectric permittivity ε and the magnetic permeability μ of the material less than zero. Unique ... 詳細を見る

Soft tissues are longest tissue structures found throughout a human body. It plays a vital role in connecting, providing support or surround other structures and organs of the body. Muscles, skin, tendons, ligaments, nerves, fibrous tissues, fat, blood vessels are commonly classified as ... 詳細を見る

Determination of Estrogen Receptor [ER] status is a key in detecting cancer pathogenesis at early stage. In our work we discuss Near Infrared Fluorescence [NIRf] Molecule Optical Imaging Diagnostic modality for early detection of breast cancer. A novel target-specific NIRf dye conjugate ... 詳細を見る

光中包含着巨大的能量，光能的利用一直是研究的热点。基于半导体纳米颗粒的吸光特性（如二氧化钛、氧化锌、四氧化三铁等），我们首先通过实验研究了在光强具有高斯分布的激发光作用下，微液滴内悬浮纳米颗粒的受迫运动，发现在液滴内产生了~mm/s的对称涡流，表明这一方法是在粘性主导的微流动下形成高速流动的有效手段。机理分析表明，这一光与液滴相互作用问题的物理机制为非均匀光热效应(温度梯度~1000K/m)及其所诱导的Marangoni对流，是一个包含光、热、物质与流体双向作用、界面张力梯度的复杂多物理场耦合流动问题。为了模拟这一实验现象，我们在COMSOL ... 詳細を見る

Manual manufacturing of inlay fixed partial denture frameworks by metal casting can take hours of dental practitioners work time. This paper introduces 3-D simulations of premanufactured inlay fixed partial denture framework assembled from laser cut sheet metal parts. The study gives a ... 詳細を見る

In biomedical research the use of animal models gives rise to several ethical problems. COMSOL Multiphysics® may be used as a non-animal technique, very useful in overcoming all these concerns. In this presentation a particular application in dermatology is shown. Bioheat equation ... 詳細を見る