摘要 |
A method and apparatus for measuring the concentration of particles in the exhaust gas of an internal combustion engine in which the exhaust gas is mixed and diluted with air in a mixing chamber (6) and supplied to a measuring filter (4) during a measurement phase. In order to establish the dilution ratio of the exhaust gas in the mixture of exhaust gases and air, valves (10, 11) are operated to supply air from an air line (13) to a bypass line (12) during a second phase. The quantity of air flow in the air line (13) is equal to the flow quantity of the exhaust gas to the mixing chamber (6). Thereby, the ratio of the quantity of particles measured by the filter (4) to the air flow in the air line (13) represents the concentration of the particles in the exhaust gas.
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