報(bào)告人：Fehmi Cirak教授
Speaker:Dr. Fehmi Cirak
主持人：肖洪副教授
Host:Dr. Hong Xiao
時(shí)間：2017年12月27日（星期三）上午10:00-12:00
Time: 10:00am-12:00am, December 27, 2017
地點(diǎn)：長(zhǎng)安校區(qū)動(dòng)力與能源學(xué)院大樓225會(huì)議室
Place:Room225, School of Power and Energy
主題：浸入式B-Spline有限元
Topic: Immersed B-Spline Finite Elements
內(nèi)容簡(jiǎn)介:
隨著工業(yè)技術(shù)的進(jìn)步,尤其是流固耦合、固體力學(xué)、計(jì)算機(jī)圖形學(xué)、3D打印、結(jié)構(gòu)重組等技術(shù)的發(fā)展，使得功能和復(fù)雜度越來(lái)越高的產(chǎn)品需要模擬、實(shí)驗(yàn)和加工制造。產(chǎn)品尺寸的模擬和設(shè)計(jì)跨越了米、厘米和亞毫米的范圍。為了應(yīng)對(duì)這些挑戰(zhàn)，新的交互式計(jì)算工具不可或缺。基于此背景，我們提出了可擴(kuò)展的浸入/嵌入邊界有限元和DG理論，其在優(yōu)化模型、流固耦合、固體力學(xué)等諸多領(lǐng)域表現(xiàn)出了強(qiáng)大的優(yōu)勢(shì)。與傳統(tǒng)的有限元相比，浸入有限元不需要刻意生成和保持邊界適應(yīng)性網(wǎng)格,只需采用無(wú)邊界適應(yīng)的全局網(wǎng)格并結(jié)合計(jì)算機(jī)圖形學(xué)輔助技術(shù)即可完成模擬。此外,該理論進(jìn)一步推廣將對(duì)計(jì)算流體力學(xué)、計(jì)算固體力學(xué)、計(jì)算機(jī)圖形學(xué)、CAD等諸多計(jì)算模擬領(lǐng)域產(chǎn)生深遠(yuǎn)的影響。
Introduction:
Advances in manufacturing, most prominently in additive manufacturing or fluid-structure interaction problems, are enabling the production of high-performance products with ever increasing functional and geometric complexity. Typically, the geometry features that can be designed reach from the product-scale in the order of tens of centimetres down to submillimetre scale. Novel interactive computational tools are indispensable to representing and exploring the corresponding vast design space. Against this backdrop, for the last several years we have been developing robust and scalable immersed/embedded boundary finite elements, which have clear advantages when applied to highly optimised geometrically complex parts. In contrast to conventional finite elements there is no need to generate and painstakingly maintain a boundary-fitted mesh. It is sufficient to have a non-boundary-fitted hexahedral voxel grid that is combined with auxiliary techniques for enforcing boundary conditions. Moreover, the voxel grid makes it possible to employ a host of multiresolution surface and volume representation techniques already available in computer graphics and computer-aided design.
報(bào)告人簡(jiǎn)介
Fehmi Cirak,劍橋大學(xué)工程系教授。1988年至2001年先后學(xué)習(xí)于德國(guó)University of Stuttgart和美國(guó)加州理工學(xué)院，2001年至2006年先后工作于加州理工學(xué)院Center for Advanced Computing Research和Jet Propulsion Laboratory（噴氣推進(jìn)實(shí)驗(yàn)室），2006年加盟劍橋大學(xué)工程系先后任Lecture、Senior Lecture和Reader。Fehmi先后在《Science》等著名雜志上以第一作者身份發(fā)表論文多篇，并擔(dān)任多個(gè)著名學(xué)術(shù)雜志副主編和編委。Fehmi首次將Subdivision Surface引入FEM， 是Isogeometric analysis概念提出的第一人，在計(jì)算機(jī)圖形學(xué)、流固耦合、固體力學(xué)、結(jié)構(gòu)力學(xué)等諸多領(lǐng)域做出了基礎(chǔ)性的開(kāi)創(chuàng)工作。
Speaker’s Biography
Fehmi Cirakstudied at University of Stuttgart and then California Institute of Technology from 1988 to 2001, and worked atCenter for Advanced Computing ResearchandJet Propulsion LaboratoryinCaltechfrom 2001 to 2006.After that, hejoinedUniversity of Cambridge asLecture, Senior Lecture and then Readeruntil now. Fehmi has published a lot of papers as first author in many academicjournals, such as "Science", and served asassociate editorofmany famous academicJournals. Also, he wasknown as theintroduction ofSubdivision Surfaceinto FEM.
