ANALYTIC EXPRESSION FOR THE MAGNETIC LEAKAGE FIELD INSIDE AND OUTSIDE OF A SLOT ON THE CYLINDRICAL SURFACE OF A DISC
Zhong Wei-Chang Nanjing Gas Turbine Research Institute, Nanjing, China
Keywords: Magnetic leakage field, Theory of magnetic dipole, Circumferential magnetization, Analytic expression, Slot
ABSTRACT
According to the author's new theory of magnetic dipole (1. Magnetic charges can't distribute uniformly and stably over the cross section, which is perpendicular to the magnetizing field, but can only distribute along all the edges of the workpiece equally. 2. There will be different functions between the slot depth in the sample surface and the magnetic leakage field, yielded from the slot due to the different test block's shapes, magnetization ways and slot depths. ), the analytic expression for the magnetic leakage field inside and outside of a slot on the cylindrical surface of a dist, at circumferential magnetization, has been derived. Their digital magnitudes at the symmetrical axis of the slot, have been calculated and plotted through this expression and the linear magnetic charge density along the edge of the slot, gained by the author's former calculation. These theoretical characteristic curves very well conform to the experimental results, which has been ever known for 22 years at least, but any theoretical explanation about this classical experiment has never been seen since then.
Publication Source: Trends in NDE Science & Technology; Proceedings of the 14th World Conference on Non-Destructive Testing, New Delhi, 8-13 December 1996.Vol. 3, pages 1581 - 1584 Publisher:Ashgate Publishing Company
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