Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Thermal Mutual Inductance


WHEN heat is dissipated from a hot body immersed in a fluid, the flow of heat is accompanied by a mechanical circulation of the fluid in the system of natural convection currents. The stored kinetic energy bestows on the heat current a property which has been termed ‘thermal ‘inductance, and curves I have obtained1 for the thermal transients consequent on the sudden heating of a cylindrical body, or wire, immersed in a fluid, clearly show the influence of this inductive element. Experiments of this nature may, however, readily be extended to show the influence of a property which may be referred to as ‘thermal mutual ‘inductance. If we take two parallel wires, one vertically above the other so that the same system of convection currents link both, then any change in the heat flow from one might be expected to influence the heat flow from the other. There are two such changes possible, a transient and a permanent one. A steady change in the heat flow from the upper wire consequent on a change in the heat flow from the lower simply represents the case of a hot-wire anemometer used to explore natural convection currents. If, however, our system is to exhibit a property of thermal mutual inductance, then we expect a transient change in the heat flow (or associated temperature difference) from the upper wire to accompany any change in the heat flow from the lower.

This is a preview of subscription content, access via your institution

Relevant articles

Open Access articles citing this article.

Access options

Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.


  • Bosworth, R. C. L., Nature, 158, 309 (1946); Phil, Mag., 37, 803 (1946).

    Article  Google Scholar 

  • Bosworth, R. C. L., J. Roy. Soc. N.S.W. (in the press).

Download references

Author information

Authors and Affiliations


Rights and permissions

Reprints and Permissions

About this article

Cite this article

BOSWORTH, R. Thermal Mutual Inductance. Nature 161, 166–167 (1948).

Download citation

  • Issue Date:

  • DOI:

This article is cited by


By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing