The Confined Hard Disk Two Piston System simulates a constant-energy two-dimensional system of unit mass particles confined by two frictionless pistons of equal mass M. This computer model complements theoretical work describing the adiabatic expansion of an ideal gas using the quasi-static approximation. Users can set the number of particles N, their diameter and their initial particle kinetic energy. Slow-moving particles are color-coded as blue and fast particles are color-coded as yellow. The time evolution of temperature, pressure, and piston speed are shown in a second window.
Particles in this model have unit mass and interact through contact forces. Collision times are computed analytically because particles and pistons move with constant velocity between collisions. The time evolution algorithm advances the particle position from collision to collision until the requested time step is achieved. The time evolution is then paused, data is accumulated, and the screen is redrawn.
The Confined Hard Disk Two Piston System is a supplemental simulation for the article "Evolution of ideal gas mixtures confined in an insulated container by two identical pistons" by Joaquim Anacleto, Joaquim Alberto C. Anacleto, and J. M. Ferreira in the American Journal of Physics 79(10), 1009-1014 (2011) and has been approved by the authors and the American Journal of Physics (AJP) editor. This model was developed using the Easy Java Simulations (Ejs) modeling tool. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the ejs_stp_hd_ConfinedHardDiskTwoPistonSystem.jar file will run the program if Java is installed.
Please note that this resource requires
at least version 1.5 of
Confined Hard Disk Two Piston System Source Code
The source code zip archive contains the EJS-XML representation of the Confined Hard Disk Two Piston System model. Unzip this archive in your EJS workspace to compile and run this model using EJS. download 23kb .zip
Last Modified: March 15, 2011
Metadata instance created
March 9, 2011
by Wolfgang Christian
June 3, 2014
by Andreu Glasmann
Last Update when Cataloged:
December 27, 2010
AAAS Benchmark Alignments (2008 Version)
4. The Physical Setting
4E. Energy Transformations
6-8: 4E/M4. Energy appears in different forms and can be transformed within a system. Motion energy is associated with the speed of an object. Thermal energy is associated with the temperature of an object. Gravitational energy is associated with the height of an object above a reference point. Elastic energy is associated with the stretching or compressing of an elastic object. Chemical energy is associated with the composition of a substance. Electrical energy is associated with an electric current in a circuit. Light energy is associated with the frequency of electromagnetic waves.
AAAS Benchmark Alignments (1993 Version)
4. THE PHYSICAL SETTING
E. Energy Transformations
4E (9-12) #2. Heat energy in a material consists of the disordered motions of its atoms or molecules. In any interactions of atoms or molecules, the statistical odds are that they will end up with less order than they began?that is, with the heat energy spread out more evenly. With huge numbers of atoms and molecules, the greater disorder is almost certain.
Christian, W. (2011). Confined Hard Disk Two Piston System Model (Version 1.0) [Computer software]. Retrieved February 20, 2017, from http://www.compadre.org/Repository/document/ServeFile.cfm?ID=10835&DocID=2188
Christian, Wolfgang. Confined Hard Disk Two Piston System Model. Vers. 1.0. Computer software. 2011. Java 1.5. 20 Feb. 2017 <http://www.compadre.org/Repository/document/ServeFile.cfm?ID=10835&DocID=2188>.
%0 Computer Program %A Christian, Wolfgang %D December 27, 2010 %T Confined Hard Disk Two Piston System Model %7 1.0 %8 December 27, 2010 %U http://www.compadre.org/Repository/document/ServeFile.cfm?ID=10835&DocID=2188
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