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Example 3

{{SimInitialize-nav}} Next, verify that the piston is not in motion. The piston is not in motion if the piston button is labeled "Release Piston". If the piston button is labeled "Hold piston", push that button.

Set the initial conditions (Any parameter not mentioned should be left at the default):

  • Use a simulation in 3D space
  • Heat transfer: Isothermal
  • Temperature: 1000
  • Pressure: 500
  • Number of Molecules: 100 (this is not editable)
  • Intermolecular Potential: Ideal gas

Run the simulation by pushing the start button and then pushing the piston button. The density graph should show the density settle at an equilibrium value. Use the piston-cylinder slider to shrink the piston-cylinder graphic to a point where the piston is visible. Next, select "Repulsion and attraction"from the intermolecular potential menu. Note the change in the piston position and the density as shown on the density graph. Now lower the temperature to 600K using the temperature slider and observe the change in density and temperature as displayed on the density graph and temperature graph. Lower the temperature further, to 300K and once again, observe the change in density. Now select "Repulsion only" from the intermolecular potential menu. Note the reaction of the density and piston travel.