Yoshizawa's cross-helicity effect and its quenching
2013 (English)In: Geophysical and Astrophysical Fluid Dynamics, ISSN 0309-1929, Vol. 107, no 1-2, 207-217 p.Article in journal (Refereed) Published
A central quantity in mean-field magnetohydrodynamics is the mean electromotive force , which in general depends on the mean magnetic field. It may however also have a part independent of the mean magnetic field. Here we study an example of a rotating conducting body of turbulent fluid with non-zero cross-helicity, in which a contribution to proportional to the angular velocity occurs (Yoshizawa, A., Self-consistent turbulent dynamo modeling of reversed field pinches and planetary magnetic fields. Phys. Fluids B 1990, 2, 15891600). If the forcing is helical, it also leads to an effect, and large-scale magnetic fields can be generated. For not too rapid rotation, the field configuration is such that Yoshizawa's contribution to is considerably reduced compared to the case without effect. In that case, large-scale flows are also found to be generated.
Place, publisher, year, edition, pages
2013. Vol. 107, no 1-2, 207-217 p.
Mean-field dynamo, Rotating turbulence, Cross-helicity effect, Alpha effect
Astronomy, Astrophysics and Cosmology Geochemistry Geophysics
IdentifiersURN: urn:nbn:se:su:diva-88961DOI: 10.1080/03091929.2012.681307ISI: 000315486300012OAI: oai:DiVA.org:su-88961DiVA: diva2:616508