Main >> Applications >> Sample problems >> Proximity effect

# Proximity effect

eddy currents in the parallel conductors, proximity effect FEA finite element analysis

In the lab the current density is defined by measuring the voltages on the conductor segments, the phase of current is measured separately by the digital phasemeter.

Problem type
Plane-parallel problem of AC magnetics.

Geometry

Given
Relative magnetic permeability of steel μ= 100
Total current I=300 A, frequency f=50 Hz
Electric conductivity of copper σ=57 MS/m
Electric conductivity of steel σ=10 MS/m.

Find the current density distribution along the cross section of long parallel conductors. Two types of conductors are analyzed: two copper rods and two steel tubes.

Solution
Due to problem symmetry only upper-right quarter aOb is defined, and at the axes of symmetry the boundary conditions are set.
At the horizontal axis of symmetry (line Oa) Ht=0. At the vertical axis of symmetry Ob Bn=0. Equation B=rot A in the cylindrical coordinate system leads to A=const at the axis Ob. Field fades at the infinity so at the other boundaries A=0.

Results
Current density distribution along the line Oa for copper rods.

Current density distribution along the steel tube perimeter (from the point e to point f clockwise).

Reference: Wikipedia: Proximity effect

 Product Order Evaluation request Editions Version history Packages Components Programming Consulting Applications Industrial Educational Scientific Sample problems Success stories Customers Support Webinars Virtual Classroom Online courses Customer login Glossary QuickField help FAQ
 Downloads QuickField Student Edition User manual Data Libraries Video Free tools News Product News Events Publications Subscription Contacts Tera Analysis info Resellers Contact us Online chat About us