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Heat Engine On A Wire


Consists of a pair of aluminum supports with holes in the center, a steel wire, and a number of small bimetallic disks.

Very finicky. Currently not in working order.

(You can try, but after a number of attempts the disk would not reliably jump from side to side.)


To demonstrate how the differing coefficients of thermal expansion in metals may be utilized. Shows a very unusual example of a heat engine.


  • Wire, aluminum supports, and bimetallic disks


Start by setting up the heat engine. Insert the wire into both of the aluminum supports, threading it through the hole in one of the bi-metallic disks at the same time. Place one of the aluminum supports onto a hotplate and turn it on to the maximum setting.

Place bi-metallic disk with concave (brass coloured) side down on the support that rests on the hot-plate. Once the disk has heated up to some critical value, it'll buckle (go from concave-side-down to convex-side-down), propelling it along the wire to the other support. Once it cools down, it'll return to it's original form, flipping over to the hot side once again.


It may be necessary to elevate one of the sides, should it turn out that the disk can't jump high enough from that side to reach the other.

Demo room information

Location —-
Maker Unknown
Current State Working
demonstrations/4_thermodynamics/4f_entropy_and_the_second_law/heat_engine_on_a_wire/start.txt · Last modified: 2019/04/24 23:18 by demoroom