The role of kinetic helicity in small-scale fast dynamo action is investigated by employing a simple statistical model for the underlying flow with statistics that are Gaussian distributed, temporally delta-correlated and spatially homogeneous and isotropic. In order to focus on small-scale dynamo action we restrict our attention to flows possessing no net kinetic helicity. With the help of a diagrammatic technique and a numerical calculation we show that the dynamo growth rate is independent of the kinetic helicity as the magnetic Reynolds number Rm → ∞. It is indicated that the latter enhances the growth of the magnetic energy only for finite Rm.
|Number of pages||8|
|Journal||Physics Letters, Section A: General, Atomic and Solid State Physics|
|Publication status||Published - 8 Dec 1997|
ASJC Scopus subject areas
- Physics and Astronomy(all)