Hour‐to‐Hour Height Variation

Rerun the single particle concentration simulation

But turn on the center‐of‐Mass trajectory output

Sensitivity of Maximum Concentration to Grid Size

Edit conc_part.bat (or .sh)
with different concentration grid resolutions: 0.10, 0.20, ...

Simulation with 100 particles

Simulation with 1000 particles

Simulation with 10000 particles

Maximum concentration differences with 0.10 grid -

• 100 to 1000 particles: 50%
• 1000 to 10000 particles: 36%

Maximum concentration differences with 0.20 grid -

• 100 to 1000 particles: 50%
• 1000 to 10000 particles: 15%

Sensitivity of Minimum Concentration to Particle Number

Edit conc_part.bat (or .sh)
for grid size 0.20 use gridplot and display plot.ps

Simulation with 100 particles ... min = 5.3E-15

Simulation with 1000 particles ... min = 5.3E-16

Simulation with 10000 particles ... min = 5.3E-17

Hypothetical example

• A finer concentration grid requires more particles
• Or fewer particles could utilize a coarser grid
• Particle number versus grid size sensitivity can be evaluated using the maximum concentration
• Minimum concentrations are also affected because the lower limit is the mass of one particle divided by the grid cell size