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<font face="serif">Guys -- to get the Jacobi tiling method I sent
you yesterday to scale properly (the room equilibrates in ~55
simulated sec) you have to be very careful about constants and
dimensions.<br>
<br>
First, here are components from the CSC 330 project...<br>
<br>
</font><tt>room_dimension = 5 ! 5 Meters</tt><tt><br>
</tt><tt>speed_of_gas_molecules = 250.0D0 ! Based on 100
g/mol gas at RT</tt><tt><br>
</tt><tt>time_between_blocks = (room_dimension /
speed_of_gas_molecules) / msize</tt><tt><br>
</tt><tt>distance_between_blocks = room_dimension / msize</tt><tt><br>
</tt><tt>area = distance_between_blocks**2</tt><tt><br>
</tt><tt>timestep = time_between_blocks</tt><font face="serif"><br>
<br>
<br>
Now -- the scalar value is what you have to multiply your "volume
change" by in the tiling code. I used the following...<br>
<br>
</font><tt>scalar = diffusion_coefficient * timestep /
distance_between_blocks**2 * 4</tt><font face="serif"><br>
<br>
Which produced the following results...<br>
<br>
<br>
<img alt="diffusion" src="cid:part1.09030206.04080309@mercer.edu"
height="480" width="640"><br>
</font><br>
Box dimension = 5.0000000 meters.<br>
Box Partition = 50 steps.<br>
Time Step = 3.99999990E-04 seconds.<br>
Diffusion C = 0.17500000 <br>
<br>
Simulation required 51.636589 seconds to reach equilibrium.<br>
<br>
Run took 51 minutes and 43.970215 seconds of
processor time.<br>
<br>
<br>
Run took 2 minutes and 10 seconds of wall
clock time.<br>
<br>
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--
Andrew J. Pounds, Ph.D. (<a class="moz-txt-link-abbreviated" href="mailto:pounds_aj@mercer.edu">pounds_aj@mercer.edu</a>)
Professor of Chemistry and Computer Science
Mercer University, Macon, GA 31207 (478) 301-5627
<a class="moz-txt-link-freetext" href="http://faculty.mercer.edu/pounds_aj">http://faculty.mercer.edu/pounds_aj</a>
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