PIRA 4F30.80 Compression Igniter


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Photo of University of Texas at Austin's Demonstration:


Faculty Instructions:

  • Unscrew the removable base from the bottom of the igniter.
  • Insert a piece of tissue paper (size: <1cm^2; separate the sheets of the tissues and use just 1 translucent sheet) about 1.5 inches through the bottom of the glass tube. If needed, use the cleaning rod to help push the tissue in.
  • Make sure the tissue lays right on top of the base once it is screwed back in. Do not clump up or wad the tissue paper tightly. The more surface area available for ignition, the better.

  • Concepts Conveyed:

  • The quick compression of air is an adiabatic process, in which the change in heat is equal to zero.
  • The temperature rises quickly (up to 600 C or 1,100 F) during adiabatic compression, so there is no time for thermal energy to leave or enter the cylinder. This results in the tissue paper igniting.
  • This demo is a great analog for the processes within the cylinder of a diesel engine.

  • Demo Staff Instructions:

  • Ensure the wooden base is clamped to the table.

  • Last Updated 2023 - University of Texas at Austin Physics Department - All Rights Reserved