Patent ID: 7647810

Claim:
A solid particle counting system for measuring solid particle number concentrations from engine or vehicle exhausts in real-time, the system comprising: a sample inlet; an evaporation unit receiving flowing gases containing volatile particles and solid particles, and heating the flowing gases to vaporize volatile particles while allowing solid particles to flow through the evaporation unit without particle losses; a diluter arrangement receiving the gases from the evaporation unit, the diluter arrangement receiving dilution gas and mixing dilution gas with the gases from the evaporation unit, the diluter arrangement providing an output flow; a particle counter receiving a portion of the output flow and measuring solid particle number concentrations in the received portion of the output flow; and wherein the diluter arrangement mixes the dilution gas with the gases from the evaporation unit at a dilution ratio, and the diluter arrangement includes a flow meter located between the sample inlet and the evaporation unit for directly measuring the total flow of gases into the evaporation unit which, in turn, flow into the diluter arrangement.