Michiya Shimada, Jabir Al Salami, Kazuaki Hanada, Changhong Hu
{"title":"A Duct Design for Reducing Grad-B MHD Drag","authors":"Michiya Shimada, Jabir Al Salami, Kazuaki Hanada, Changhong Hu","doi":"10.1007/s10894-023-00388-2","DOIUrl":null,"url":null,"abstract":"<div><p>Harsh heat load conditions on plasma-facing components (PFCs) in steady-state and transient phenomena (e.g., disruptions and ELMs) in DEMO fusion reactors question the feasibility of current approaches based on solid targets made of tungsten. This issue calls for the development of innovative plasma-facing components. Liquid metal PFCs with strong convection enhance heat removal capability and resilience after the transient phenomena. However, transporting liquid metal across magnetic fields gives rise to MHD drag. MHD drag for the case of uniform <b><i>B</i></b>, estimated analytically, is acceptable. Grad-<b><i>B</i></b> MHD drags with straight ducts could seriously drag the LM flow across non-uniform <b><i>B</i></b>. Expanding the duct along <b><i>B</i></b> and shrinking the duct in a perpendicular direction could make electromotive force |<b><i>vBh</i></b>| approximately constant along the duct and significantly reduces the grad-B MHD drag. Here <b><i>v</i></b> denotes the flow velocity along the duct, <b><i>B</i></b> is the magnetic field strength, and <b><i>h</i></b> is the vertical duct size. Three-dimensional simulations for internal and free surface thermo-MHD phenomena have demonstrated that the proposed duct design reduces the total pressure drop along the duct.</p></div>","PeriodicalId":634,"journal":{"name":"Journal of Fusion Energy","volume":null,"pages":null},"PeriodicalIF":1.9000,"publicationDate":"2023-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Fusion Energy","FirstCategoryId":"5","ListUrlMain":"https://link.springer.com/article/10.1007/s10894-023-00388-2","RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"NUCLEAR SCIENCE & TECHNOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Harsh heat load conditions on plasma-facing components (PFCs) in steady-state and transient phenomena (e.g., disruptions and ELMs) in DEMO fusion reactors question the feasibility of current approaches based on solid targets made of tungsten. This issue calls for the development of innovative plasma-facing components. Liquid metal PFCs with strong convection enhance heat removal capability and resilience after the transient phenomena. However, transporting liquid metal across magnetic fields gives rise to MHD drag. MHD drag for the case of uniform B, estimated analytically, is acceptable. Grad-B MHD drags with straight ducts could seriously drag the LM flow across non-uniform B. Expanding the duct along B and shrinking the duct in a perpendicular direction could make electromotive force |vBh| approximately constant along the duct and significantly reduces the grad-B MHD drag. Here v denotes the flow velocity along the duct, B is the magnetic field strength, and h is the vertical duct size. Three-dimensional simulations for internal and free surface thermo-MHD phenomena have demonstrated that the proposed duct design reduces the total pressure drop along the duct.
期刊介绍:
The Journal of Fusion Energy features original research contributions and review papers examining and the development and enhancing the knowledge base of thermonuclear fusion as a potential power source. It is designed to serve as a journal of record for the publication of original research results in fundamental and applied physics, applied science and technological development. The journal publishes qualified papers based on peer reviews.
This journal also provides a forum for discussing broader policies and strategies that have played, and will continue to play, a crucial role in fusion programs. In keeping with this theme, readers will find articles covering an array of important matters concerning strategy and program direction.