The standing MHD modes in a zero-β cylindrical magnetic flux tube modelled as a straight core surrounded by a magnetically twisted annulus, both embedded in a straight ambient external field is considered. The dispersion relation for the fast MHD waves is derived and solved numerically to obtain the frequencies of both the kink (m = 1), and fluting (m = 2, 3) waves. Damping rates due to both vi...

The standing magnetohydrodynamic (MHD) modes in a cylindrical incompressible magnetic flux tube modelled as a straight core surrounded by a magnetically twisted annulus, both embedded in a straight ambient external field, are considered. The dispersion relation for the MHD waves is derived and solved numerically to obtain the frequencies of both the kink (m = 1) and fluting (m = 2, 3) waves. Da...

Aims. We study kink and fluting oscillations of a straight magnetic tube with an elliptic cross-section and density varying along the tube. Methods. The governing equations for kink and fluting modes in the thin tube approximation are derived. We found that there are two kink modes, polarised along the semimajor and semiminor axes of the elliptic cross-section. We have shown that the ratio of f...

voltage source inverters. An example of bearing fluting is shown and system models presented and discussed. The construction details and test results for several ESIMs are presented. Experimental results show the ESIM solves the electrostatically induced rotor shaft voltage and bearing problem without degrading the electromagnetic performance of the motor.

The fluting instability has been suggested as the driver of subsurface structure sunspot flux tubes. We conducted a series numerical experiments where we used tubes with different initial curvatures to study effect on spots. MURaM code, which previously simulate complete sunspots, first compute four sunspots in slab geometry and then two circular spots opposite polarities. find that curvature t...

Corn stalk, an agricultural waste, was valorized by the production of cellulose nanofibers (CNF), which were tested for improving recycled paper properties. CNF from eucalyptus kraft pulp (E-CNF) was used as a reference. Addition of 0.5% wt. CNF produced from corn organosolv pulp (C-CNF) to recycled paper increased the tensile index by 20%, whereas the same improvement with E-CNF was achieved a...