Abstract: A system including a sampling flute is provided. The sampling flute defines a conduit therein. The sampling flute includes a plurality of holes configured for allowing passage of an exhaust gas flow therethrough. The system also includes a hood provided on the sampling flute. The hood is configured to enclose a nitrogen oxide sensor therein. The hood includes an inlet in fluid communication with the sampling flute. The hood also includes an outlet positioned opposed to the inlet. The hood is configured to cause the exhaust gas flow to impact a side of the nitrogen oxide sensor.

Abstract: Accurate measurement of exhaust gas compounds is necessary for correct operation of exhaust treatment systems, such as Selective Catalytic Reduction (SCR) units used in diesel engines. However, accurate sensor readings assume an even distribution of compounds in an exhaust stream in order to use a sampled measurement to be extrapolated to the compound concentrations in the full stream. A structure placed in an exhaust passage downstream of an SCR reaction unit causes turbulence in the exhaust gas while developing a minimal backpressure. This turbulence helps create a more uniform distribution of compounds in the exhaust. As a result, an exhaust gas sensor gives more accurate readings even when the sensor is placed in relatively close proximity to an output of the SCR system.

Abstract: Accurate measurement of exhaust gas compounds is necessary for correct operation of exhaust treatment systems, such as Selective Catalytic Reduction (SCR) units used in diesel engines. However, accurate sensor readings assume an even distribution of compounds in an exhaust stream in order to use a sampled measurement to be extrapolated to the compound concentrations in the full stream. A structure placed in an exhaust passage downstream of an SCR reaction unit causes turbulence in the exhaust gas while developing a minimal backpressure. This turbulence helps create a more uniform distribution of compounds in the exhaust. As a result, an exhaust gas sensor gives more accurate readings even when the sensor is placed in relatively close proximity to an output of the SCR system.