XGAS(1) X Version 11 (Release 5) XGAS(1)
NAME
xgas - animated simulation of an ideal gas
SYNOPSIS
xgas [-option ...]
DESCRIPTION
xgas is a physical simulation of an ideal gas in a heated
box. Gas molecules move around the box with velocities
dependent on their temperature. A chamber consisting of two
boxes contains the gas molecules; the temperature of each
box can be independently controlled by a scrollbar. When
gas molecules collide with the walls, their temperature
approaches that of the box.
Use mouse button 1 to create molecules one at a time at the
cursor position. Use mouse button 2 to create the maximum
number of molecules at the cursor position.
OPTIONS
This is a toolkit program;
all the usual toolkit options are available.
-ts Sets the timeStepSize resource.
-d Sets the delay resource.
-rb Sets the randomBounce resource.
-eq Sets the equilibrium resource.
-mm Sets the maxMolecules resource.
-fg Sets the foreground.
-bg Sets the background.
RESOURCES
The xgas program uses the following X resources:
timeStepSize
Specifies the simulated time duration in
microseconds for each cycle of computation.
delay Specifies the real time interval between timestep
computations.
randomBounce
In each wall collision, a molecule bounces
elastically (angle of incidence = angle of
reflection). A component of randomness is added to
this angle. RandomBounce varies from 0.0 (no
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XGAS(1) X Version 11 (Release 5) XGAS(1)
randomness) to 1.0 (completely random angle of
incidence).
equilibrium
During each wall collision, a molecule's kinetic
energy approaches that corresponding to the
temperature of the wall. If equilibrium is 1.0, the
molecule reaches the wall temperature immediately.
For values between 1.0 and 0.0, the molecule
approaches the temperature of the wall more slowly.
maxMolecules
Specifies the maximum number of molecules in the
simulation.
SEE ALSO
X(1), xwd(1)
BUGS
When the chamber is resized, molecules should be rearranged
appropriately. Instead, the molecule arrays are
reinitialized.
COPYRIGHT
Copyright 1991, Massachusetts Institute of Technology.
AUTHOR
Larry Medwin
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