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 Physico-chemical conditions in the gas phase Flow fields & residence times Particle composition Particle shape

4. Aerosol formation in a laminar flow reactor

5. Simulation results Saturation ratio [ - ] Nucleation rate [#/Ncm 3 /s] Particle concentration [#/Ncm 3 ] 600 200 0 3E5 2E5 1E5 5E4 4E4 3E4 2E4 1E4 0 0 400

6. Accuracy of the simulations Computationally Vs. experiments

7. Deposit Formation Turbulent flow in panel heat heat exchangers

8. Stagnation point boundary layer Fume: 20 g/Nm 3 NaCl: 1 g/Nm 3  C Flow: 5 m/s, 900  C  C Surface: 480  C Max Saturation: CFD: 24.0 SPM: 24.3 30 0 21 16 0.41 0.4 1000 400 1.5 0 3.1 2.7 0.0 2.0

9. Deposition & Sootblowing cycle Fume: 20 g/Nm 3 NaCl: 1 g/Nm 3  C Flow: 5 m/s, 900  C Deposit height [mm] Dep. rate [g/m 2 /min] Temperature [  C] NaCl Dep. rate [g/m 2 /min] 150 0 0

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