Encyclopedia Magnetica™

Calculator of effective magnetic permeability from air gap

This section is an interactive calculator.

For a magnetic circuit with uniform cross-section the value of effective permeability μ_eff can be calculated if the lengths and permeabilities of both parts are known.

$$ \mu_{eff} = \frac{\mu_{core}}{ {\frac{l_{gap}}{l_{core}} ⋅ \mu_{core} + 1 } } $$

(unitless)

Note: The equation is valid only for a simple magnetic circuit, with cross-sectional area of the core and gap being equal, for relative permeability if l_core » l_gap, and if µ_core » 1.

Calculators, Permeability