I am trying to create a spreadsheet or find a closed-form solution to determine the heat transfer rate, flux, and heat generated per unit volume for a cross section of an electrical conduit which consists of multiple copper conductors surrounded by various layers of insulating material. If possible, I would like to determine the material properties for a single theoretical material that would have the same heat generation and heat transfer properties as the actual electrical conduit. The conduit has a variable number of conductors and insulation thicknesses, so being able to solve for a theoretical material with a similar heat signature would greatly simplify our FEA analysis. It seems to me this must have been tried by somebody else before. Anyone out there have any ideas?

Are you trying to find the steady state temperature distribution based on current flow through one or all of the conductors?

Don Leffingwell

There is current flow through all of the conductors, [which is known] and the analysis is for a steady-state condition.

Check EIA Standard RS-214 "Method for Calculation of Current Ratings on Hookup Wire" (November 1958), I have developed a Mathcad worksheet to illustrate this recommended practice for calculating the current rating for a single wire. There is much literature on the subject. Good luck. Bill B.

William H. Bernhart, P.E.


I work as a development engineer for AMP - Tyco Electronics located near Harrisburg, PA. I help design interconnections and electrical connectors for aerospace applications.