Test Tube Stirling Engine

Introduction: Test Tube Stirling Engine

Above is a short video clip of a simple test tube stirling engine using glass marbles as the displacer and a glass syringe as the power piston.

This simple Stirling engine was built from materials that are available in most school science labs and can be used to demonstrate a simple heat engine.

Pressure volume diagram for the cycle

Process 1→2          Expansion of working gas on hot end of test tube, heat is transferred into gas and gas expands thus increasing volume and pushing syringe piston upwards.

Process 2→3           As marbles move to the hot end of the test tube gas is displaced from the hot end of the test tube to the cold end, as gas moves it gives up heat into the test tube wall.

Process 3→4           Heat is removed from the working gas and volume decreases, the syringe piston moves downwards.

Process 4→1           Completes the cycle working gas moves from the cold end of the test tube to the hot end, as the marbles displace it, acquiring heat from the test tube wall as it moves thus increasing the gas pressure.

Teacher Notes

Teachers! Did you use this instructable in your classroom?
Add a Teacher Note to share how you incorporated it into your lesson.

Be the First to Share


    • Backyard Contest

      Backyard Contest
    • Silly Hats Speed Challenge

      Silly Hats Speed Challenge
    • First Time Author Contest

      First Time Author Contest


    Bill WW
    Bill WW

    6 years ago on Introduction

    WOW! Even a thermodynamic P-V diagram!

    I have never seen a test tube Stirling engine, very impressive.
    I have made two Stirling engines, may get around to posting them.