Computational simulation of

1

• Computational simulation of
• aerosol behaviour
• Jouni Pyykönen
• Lectio Praecursoria
• 22. 3. 2002

2
Aerosols - Important in many processes
3
Many dimensions in aerosol issues
Particle size
Particle composition
Physico-chemical conditions in the gas phase
Particle shape
Flow fields residence times
4
Aerosol formation in a laminar flow reactor
5
Simulation results
Nucleation rate /Ncm3/s
Particle concentration /Ncm3
Saturation ratio -
5E4
600
3E5
4E4
2E5
400
3E4
2E4
200
1E5
1E4
0
0
0
6
Accuracy of the simulations
Vs. experiments
Computationally
7
Deposit Formation
Turbulent flow in panel heat heat exchangers
8
Stagnation point boundary layer
1000
30
Fume 20 g/Nm3 NaCl 1 g/Nm3 Flow 5 m/s, 900
?C Surface 480 ?C Max Saturation CFD
24.0 SPM 24.3
400
0
21
1.5
0
16
0.41
3.1
0.4
2.7
2.0
0.0
9
Deposition Sootblowing cycle
Temperature ?C
Deposit height mm
Fume 20 g/Nm3 NaCl 1 g/Nm3 Flow 5 m/s, 900
?C
0
150
Dep. rate g/m2/min
0
150
NaCl Dep. rate g/m2/min
10

• Computational simulation of
• aerosol behaviour
• Jouni Pyykönen
• Lectio Praecursoria
• 22. 3. 2002