{"@context":{"@vocab":"https://cir.nii.ac.jp/schema/1.0/","rdfs":"http://www.w3.org/2000/01/rdf-schema#","dc":"http://purl.org/dc/elements/1.1/","dcterms":"http://purl.org/dc/terms/","foaf":"http://xmlns.com/foaf/0.1/","prism":"http://prismstandard.org/namespaces/basic/2.0/","cinii":"http://ci.nii.ac.jp/ns/1.0/","datacite":"https://schema.datacite.org/meta/kernel-4/","ndl":"http://ndl.go.jp/dcndl/terms/","jpcoar":"https://github.com/JPCOAR/schema/blob/master/2.0/"},"@id":"https://cir.nii.ac.jp/crid/1361699994739650944.json","@type":"Article","productIdentifier":[{"identifier":{"@type":"DOI","@value":"10.1017/s0022112085003251"}},{"identifier":{"@type":"URI","@value":"https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022112085003251"}}],"dc:title":[{"@value":"Magnetostatic equilibria and analogous Euler flows of arbitrarily complex topology. Part 1. Fundamentals"}],"description":[{"type":"abstract","notation":[{"@value":"<jats:p>The well-known analogy between the Euler equations for steady flow of an inviscid incompressible fluid and the equations of magnetostatic equilibrium in a perfectly conducting fluid is exploited in a discussion of the existence and structure of solutions to both problems that have arbitrarily prescribed topology. A method of magnetic relaxation which conserves the magnetic-field topology is used to demonstrate the existence of magnetostatic equilibria in a domain [Dscr    ] that are topologically accessible from a given field <jats:bold>\n\t      <jats:italic>B</jats:italic>\n\t    </jats:bold><jats:sub>0</jats:sub>(<jats:italic>x</jats:italic>) and hence the existence of analogous steady Euler flows. The magnetostatic equilibria generally contain tangential discontinuities (i.e. current sheets) distributed in some way in the domain, even although the initial field <jats:bold>\n\t      <jats:italic>B</jats:italic>\n\t    </jats:bold><jats:sub>0</jats:sub>(<jats:italic>x</jats:italic>) may be infinitely differentiable, and particular attention is paid to the manner in which these current sheets can arise. The corresponding Euler flow contains vortex sheets which must be located on streamsurfaces in regions where such surfaces exist. The magnetostatic equilibria are in general stable, and the analogous Euler flows are (probably) in general unstable.</jats:p>\n\t  <jats:p>The structure of these unstable Euler flows (regarded as fixed points in the function space in which solutions of the unsteady Euler equations evolve) may have some bearing on the problem of the spatial structure of turbulent flow. It is shown that the Euler flow contains blobs of maximal helicity (positive or negative) which may be interpreted as ‘coherent structures’, separated by regular surfaces on which vortex sheets, the site of strong viscous dissipation, may be located.</jats:p>"}]}],"creator":[{"@id":"https://cir.nii.ac.jp/crid/1381699994739650944","@type":"Researcher","foaf:name":[{"@value":"H. K. Moffatt"}]}],"publication":{"publicationIdentifier":[{"@type":"PISSN","@value":"00221120"},{"@type":"EISSN","@value":"14697645"}],"prism:publicationName":[{"@value":"Journal of Fluid Mechanics"}],"dc:publisher":[{"@value":"Cambridge University Press (CUP)"}],"prism:publicationDate":"1985-10","prism:volume":"159","prism:startingPage":"359","prism:endingPage":"378"},"reviewed":"false","dc:rights":["https://www.cambridge.org/core/terms"],"url":[{"@id":"https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022112085003251"}],"createdAt":"2006-04-20","modifiedAt":"2025-06-21","relatedProduct":[{"@id":"https://cir.nii.ac.jp/crid/1050860322104241152","@type":"Article","resourceType":"学術雑誌論文(journal article)","relationType":["isReferencedBy"],"jpcoar:relatedTitle":[{"@language":"en","@value":"Nested invariant tori foliating a vector field and its curl: Toward MHD equilibria and steady Euler flows in toroidal domains without continuous Euclidean isometries"}]},{"@id":"https://cir.nii.ac.jp/crid/1360285707409458432","@type":"Article","resourceType":"学術雑誌論文(journal article)","relationType":["isReferencedBy"],"jpcoar:relatedTitle":[{"@value":"Local representation and construction of Beltrami fields"}]},{"@id":"https://cir.nii.ac.jp/crid/1360285709376485888","@type":"Article","resourceType":"学術雑誌論文(journal article)","relationType":["isReferencedBy"],"jpcoar:relatedTitle":[{"@value":"Spatial evolution of the helical behavior and the 2/3 power-law in single-square-grid-generated turbulence"}]},{"@id":"https://cir.nii.ac.jp/crid/1360567182400936064","@type":"Article","resourceType":"学術雑誌論文(journal article)","relationType":["isReferencedBy"],"jpcoar:relatedTitle":[{"@value":"Motion of Axisymmetric Magnetic Eddies with Swirl"}]},{"@id":"https://cir.nii.ac.jp/crid/1360568467159826688","@type":"Article","resourceType":"学術雑誌論文(journal article)","relationType":["isReferencedBy"],"jpcoar:relatedTitle":[{"@value":"Local representation and construction of Beltrami fields II.solenoidal Beltrami fields and ideal MHD equilibria"}]}],"dataSourceIdentifier":[{"@type":"CROSSREF","@value":"10.1017/s0022112085003251"},{"@type":"CROSSREF","@value":"10.1088/0169-5983/48/2/021404_references_DOI_96ZVQK7M3lqMY7aTLJuH48OBqCc"},{"@type":"CROSSREF","@value":"10.1063/5.0151955_references_DOI_RjEyETZd3ZZQAQKQNzPwP5alqBb"},{"@type":"CROSSREF","@value":"10.1016/j.piutam.2013.03.028_references_DOI_96ZVQK7M3lqMY7aTLJuH48OBqCc"},{"@type":"CROSSREF","@value":"10.1016/j.physd.2019.06.008_references_DOI_96ZVQK7M3lqMY7aTLJuH48OBqCc"},{"@type":"CROSSREF","@value":"10.1016/j.physd.2019.02.003_references_DOI_96ZVQK7M3lqMY7aTLJuH48OBqCc"}]}