Dekati High Temperature ELPI+ Jonna Kannosto Technical Marketing Spesialist, PhD

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1 Dekati High Temperature ELPI+ Jonna Kannosto Technical Marketing Spesialist, PhD

2 Hot particle sample

3 Sample conditioning Sampling dynamics Nucleation Condensation Evaporation Coagulation Effect of dilution parameters Temperature Residence time Humidity Dilution ratio Particle Losses Inertial Gravitational Turbulent Diffusion Thermophoretic Electrophoretic Jonna Kannosto

4 ELPI+ Real-time particle size distribution 6 nm 10 µm Operation Charger: particle charging Impactor: particle size classification Electrometers: electrical detection of charged particles

5 High Temperature ELPI+ Same operating principle as ELPI+ Charger+Impactor moved to external heating unit, max 180 C Allows hot aerosol size and charge distribution measurement in real-time

6 High Temperature ELPI+ 6 nm 10 µm 10 lpm 10/1 Hz Max 180 ºC! Heater power 500 W Max. 1000/500 W for External heater (230V/110V) Temperature measurements Sample inlet Impactor outlet Heater Pre-set calibration values 60, 120 and 180 C Calculation sheet provided for other temperatures

7 HT-ELPI+ Collection Foils Aluminium foils Greased aluminium foils, max 100 C Apiezon-L grease, max 100 C Same for Dekati Collection Substrate Spray Apiezon-H grease, max 200 C Polycarbonate collection foils, max 140 C HT-ELPI+ not yet compatible with sintered collection plates

8 Effect of Temperature on ELPI+ Calibration Impactor cutpoint calculation is based on pressure measurement and known (calibrated) Stokes numbers Järvinen, A., Aitomaa, M., Rostedt, A., Keskinen, J. & Yli- Ojanperä, J Calibration of the new electrical low pressure impactor (ELPI+) J. Aerosol Sci. 69, pp Hillamo, R. E., & Kauppinen, E. I. (1991). On the performance of the Berner low pressure impactor. Aerosol Science and Technology, 14(1), Temperature changes gas flow rate, jet velocity in the impactor nozzles, gas viscosity and mean free path Charger efficiency assumed to remain constant 21 C 100 C 180 C Stage D50, µm D50, µm D50, µm C 100 C 180 C Flow [lpm]

9 Impactor internal temperatures during heating

10 Test engine MY 1999, 2 liter MB W124 Gasoline engine, converted for natural gas use, VTT engine dynamometer Exhaust gas synthesizer to mimic large bore natural gas engine exhaust composition Tests at kw

11 Natural gas engine test bench Flow control Exhaust out 80 kg/h Pump / flow control GAS INJECTION Methane Propane Ethane Ethene Exhaust in 80 kg/h Mass flow controller Mass flow controller Mass flow controller Mass flow controller NOx analyzer NOx sensor SCR FTIR T 400 ºC Heating unit for exhaust gas L 2100 mm Particle mass measurement (ISO-8178) Mass flow measurement Urea injection Porous tube diluter DR 6 * 4 CO2, CO, O2, NOx analyzer FTIR THC / CH4 analyzer HT-ELPI+ Ejector diluter Thermodenuder T ºC NOx sensor T 420 ºC Nano-SMPS DMA 3085 UCPC 3025

12 HT-ELPI+ results: size distribution Highly charged particles # / cm mg/m 3 (7000 #/cm 3 for >10 nm)

13 Comparison to diluted measurements Number [#/cm3] HT-ELPI+ 3.0e+4 HT-ELPI+ >10 nm 7.0e+3 SMPS Without TD 3.5e7 SMPS With TD 2.7e6 Mass [mg/m3] HT-ELPI+ (dens=1) ISO 8178 (AVL SS) 7000

14 Result: Charge levels 3093 rpm, 33 Nm, 11 kw, Ethene + Propane injection #/cm mg/m3

15 HT-ELPI+ Same advantages as with ELPI+ Direct measurement of sample in source conditions High Temperature measurement, up to 180 C No dilution required No uncertainties or particle transformations caused by dilution Improved sensitivity Low concentration measurements Diluted measurements may provide different results Things to consider Sample concentration Sample temperature Heating time (stainless steel impactor) Collection foil material (max temperature) Connection to the pump (max temperature)

16 High Temperature ELPI+ : Applications Engine emissions Tailpipe particle characterization Solid particle research OBD sensor studies at OBD conditions Tailpipe particle charging studies Particle formation studies PEMS Stationary source emission measurements Emission characterization Direct measurements from wet stacks After treatment device characterization studies Low concentration measurements Particle formation studies Particle charging studies

17 Excellence in Particle Measurements Questions?