SYSTEM FOR TAKING EXHAUST GAS SAMPLES FROM INTERNAL COMBUSTION ENGINES

摘要

A system for taking exhaust gas samples from internal combustion engines includes an exhaust gas duct comprising an outflow cross section and an exhaust gas inlet. The exhaust gas duct communicates with an exhaust gas source via the exhaust gas inlet. An air duct takes in ambient air via a filter. The outflow cross section is concentric in the air duct. A mixing zone is arranged downstream of the outflow cross section. A dilution tunnel has an exhaust gas/air mixture flow therethrough. An annular orifice is arranged downstream of the outflow cross section in the dilution tunnel. A flow deflection device is arranged upstream of the annular orifice and downstream of the outflow cross section. The flow deflection device deflects the exhaust gas/air mixture so that it departs from a center axis of the dilution tunnel immediately downstream of the flow deflection device in an axially symmetrical manner.