Robust Sample Conditioning (PMP TYPE)

The sample conditioning system of the Engine Exhaust Particle Measurement System (EEPMS) combines:

• A hot dilution stage using a porous tube diluter with no moving parts
• A heated sample line
• A catalytic stripper for removing volatile and semi-volatile particles
• A cold dilution stage with another porous tube diluter 

The total flow rate at each dilution stage is 10 L/min ensuring particle losses by diffusion are minimized. The dilution ratio at each stage of dilution is accurately controlled in real time with advanced mass flow controllers. This sample conditioning system is the next generation approach to address sub-23nm solid particle emissions.