Abstract: An exhaust gas sampling system according to the principles of the present disclosure includes a dilution air source that provides dilution air to a first flow path and a first flow meter that measures a first mass flow rate in the first flow path. The system further includes a sampling probe, a second flow meter, a first valve, and a leak detection module. The sampling probe provides exhaust gas to the first flow path at a location downstream from the first flow meter. The second flow meter measures a second mass flow rate in the first flow path at a location downstream from the sampling probe. The first valve regulates exhaust gas flow from the sampling probe to the second flow meter. The leak detection module detects a leak in the system based on measurements of the first and second mass flow rates taken when the first valve is closed.

Abstract: An exhaust gas sampling system according to the principles of the present disclosure includes a dilution air source that provides dilution air to a first flow path and a first flow meter that measures a first mass flow rate in the first flow path. The system further includes a sampling probe, a second flow meter, a first valve, and a leak detection module. The sampling probe provides exhaust gas to the first flow path at a location downstream from the first flow meter. The second flow meter measures a second mass flow rate in the first flow path at a location downstream from the sampling probe. The first valve regulates exhaust gas flow from the sampling probe to the second flow meter. The leak detection module detects a leak in the system based on measurements of the first and second mass flow rates taken when the first valve is closed.

Abstract: An emissions test apparatus is provided and may include a filter housing having at least one of a first RFID tag and a first bar code identifying the filter housing. A filter media may be selectively disposed within the filter housing and may include at least one of a second RFID tag and a second bar code identifying the filter media. A controller may link the filter housing and the filter media when the filter media is disposed within the filter housing based on information provided by the at least one of the first RFID tag and the first bar code and the at least one of the second RFID tag and the second bar code.

Abstract: Disclosed is an exhaust sampling system including a plurality of exhaust sampling system zones. The zones are, at least, a sampling conduit, a fill circuit, and a read circuit. A controller is programmed to predict a minimum dilution ratio to avoid condensation in one of the exhaust sampling system zones. The controller is further programmed to run a test procedure in which a sample of exhaust is diluted with a make-up gas at a selected minimum dilution ratio that is greater than or equal to the predicted minimum dilution ratio. Further disclosed are methods of predicting whether condensation occurs during a test procedure.

Abstract: Disclosed is an exhaust sampling system including a plurality of exhaust sampling system zones. The zones are, at least, a sampling conduit, a fill circuit, and a read circuit. A controller is programmed to predict a minimum dilution ratio to avoid condensation in one of the exhaust sampling system zones. The controller is further programmed to run a test procedure in which a sample of exhaust is diluted with a make-up gas at a selected minimum dilution ratio that is greater than or equal to the predicted minimum dilution ratio. Further disclosed are methods of predicting whether condensation occurs during a test procedure.

Abstract: An emissions test apparatus is provided and may include a filter housing having at least one of a first RFID tag and a first bar code identifying the filter housing. A filter media may be selectively disposed within the filter housing and may include at least one of a second RFID tag and a second bar code identifying the filter media. A controller may link the filter housing and the filter media when the filter media is disposed within the filter housing based on information provided by the at least one of the first RFID tag and the first bar code and the at least one of the second RFID tag and the second bar code.

Abstract: Disclosed is an exhaust sampling system including a plurality of exhaust sampling system zones. The zones are, at least, a sampling conduit, a fill circuit, and a read circuit. A controller is programmed to predict a minimum dilution ratio to avoid condensation in one of the exhaust sampling system zones. The controller is further programmed to run a test procedure in which a sample of exhaust is diluted with a make-up gas at a selected minimum dilution ratio that is greater than or equal to the predicted minimum dilution ratio. Further disclosed are methods of predicting whether condensation occurs during a test procedure.

Abstract: A particulate sampler system includes a diluted exhaust mass flow controller that receives flow from a dilution mass flow controller and a laminar flow element (LFE). The dilution mass flow controller and LFE are fluidly arranged parallel to one another. A controller communicates with the mass flow controllers and the LFE to determine the flow through these devices, command valves in the mass flow controllers and generate data for determining calibration coefficients and correction factors. The diluted exhaust mass flow controller is calibrated and calibration coefficients are generated using a first to fourth order curve fit. Similarly, initial calibration coefficients are generated for the dilution mass flow controller. The diluted exhaust mass flow controller is set at a desired flow point. The dilution mass flow controller is varied between set points corresponding to different dilution ratios at the common, desired set point.

Abstract: An exhaust emission analysis system is provided that includes an exhaust and dilution gas source respectively providing exhaust and dilution gases. A dilution unit includes exhaust and dilution gas mass flow controllers, fluidly connected to the exhaust and dilution gas sources. The mass flow controllers define a gas flow rate of gas from their respective gas source. A connection mixes the gases to provide a diluted exhaust gas having an incorrect dilution ratio. A water measurement device measures the water content of the exhaust gas. A water content dilution signal is sent from the water measurement device to a control device. An adjustment factor is calculated by the controller and a flow rate command signal is sent from the controller, to the exhaust gas mass flow controller to adjust the gas flow rate of the exhaust gas and provide a corrected dilution ratio at the connection.

Abstract: An exhaust sampling system is provided that includes a sampler having a sample inlet for receiving an exhaust gas sample. The sampler includes a mixer for receiving the exhaust gas sample and a diluent to produce a diluted exhaust gas. The exhaust sampling system includes first and second dilution gas flow devices. The first and second dilution gas flow devices are fluidly connected to one another at a second junction. Any diluent provided by the first and second dilution gas flow devices intermingles with one another prior to reaching the mixer. A diluted sample flow meter is arranged downstream from the mixer for receiving the diluted exhaust gas. In one example, diluent flow from the first and second dilution gas flow devices intermingles before being introduced to the mixer. In another example, diluent flow from the first dilution gas flow device is leaked out of the second dilution gas flow device in a controlled manner to achieve a desired diluent flow into the mixer.

Abstract: An exhaust sampling system is provided that includes a sampler having a sample inlet for receiving an exhaust gas sample. The sampler includes a mixer for receiving the exhaust gas sample and a diluent to produce a diluted exhaust gas. The exhaust sampling system includes first and second dilution gas flow devices. The first and second dilution gas flow devices are fluidly connected to one another at a second junction. Any diluent provided by the first and second dilution gas flow devices intermingles with one another prior to reaching the mixer. A diluted sample flow meter is arranged downstream from the mixer for receiving the diluted exhaust gas. In one example, diluent flow from the first and second dilution gas flow devices intermingles before being introduced to the mixer. In another example, diluent flow from the first dilution gas flow device is leaked out of the second dilution gas flow device in a controlled manner to achieve a desired diluent flow into the mixer.

Abstract: An emission sampling system includes an exhaust gas probe for sampling exhaust gas. A dilution gas source provides a dilution gas, and a mixing device is in fluid communication with the exhaust gas probe and the dilution gas source to mix the sampled exhaust gas and the dilution gas to form a diluted exhaust gas. A particulate filter is in fluid communication with the mixing device downstream therefrom. A dilution temperature conditioning device is arranged between the dilution gas source and the mixing device for obtaining a desired dilution gas temperature. A temperature sensor is arranged in the sampling system for producing a temperature signal corresponding to a temperature of fluid flowing through the sampling system. A controller is connected to the temperature sensor for processing the temperature signal and determining a filter temperature from the temperature signal. The controller commands the conditioning device in response to the filter temperature.

Abstract: A particulate sampler system includes a diluted exhaust mass flow controller that receives flow from a dilution mass flow controller and a laminar flow element (LFE). The dilution mass flow controller and LFE are fluidly arranged parallel to one another. A controller communicates with the mass flow controllers and the LFE to determine the flow through these devices, command valves in the mass flow controllers and generate data for determining calibration coefficients and correction factors. The diluted exhaust mass flow controller is calibrated and calibration coefficients are generated using a first to fourth order curve fit. Similarly, initial calibration coefficients are generated for the dilution mass flow controller. The diluted exhaust mass flow controller is set at a desired flow point. The dilution mass flow controller is varied between set points corresponding to different dilution ratios at the common, desired set point.

Abstract: A vehicle exhaust measurement system is provided includes that a conduit having a conduit inlet and a conduit outlet. A make-up air tube is connected to and is in fluid communication with the conduit inlet. The make-up air tube provides make-up air for mixing an exhaust gas. A mixed gas tube is connected to and is in fluid communication with the conduit outlet. The mixed gas tube conveys a mixture of make-up air and exhaust gas to analysis equipment. In the preferred embodiment, the exhaust gas tube extends through an outer wall of the conduit. A mixing plate is arranged in either the conduit or the mixed gas tube with the exhaust gas tube extending to a position adjacent to the mixing plate. The exhaust gas tube conveys the exhaust gas to the mixing plate to mix the exhaust gas and the make-up air at the mixing plate.

Abstract: A vehicle exhaust measurement system is provided includes that a conduit having a conduit inlet and a conduit outlet. A make-up air tube is connected to and is in fluid communication with the conduit inlet. The make-up air tube provides make-up air for mixing an exhaust gas. A mixed gas tube is connected to and is in fluid communication with the conduit outlet. The mixed gas tube conveys a mixture of make-up air and exhaust gas to analysis equipment. In the preferred embodiment, the exhaust gas tube extends through an outer wall of the conduit. A mixing plate is arranged in either the conduit or the mixed gas tube with the exhaust gas tube extending to a position adjacent to the mixing plate. The exhaust gas tube conveys the exhaust gas to the mixing plate to mix the exhaust gas and the make-up air at the mixing plate.

Abstract: An exhaust gas measurement system is provided that includes a probe to find a sample exhaust gas passageway for collecting exhaust gas. A stainless steel canister is fluidly connected to the probe for storing the exhaust gas. A pump fluidly interconnects the probe and the canister for transferring the exhaust gas from the probe to the canister. A pressure mass flow controller fluidly interconnects the probe and the canister and produces an exhaust gas flow measurement corresponding to the flow of the exhaust gas from the probe to the canister. A temperature sensor senses a temperature of the exhaust gas proximate to the pressure mass flow controller. The temperature sensor corrects the exhaust gas flow measurement based upon the temperature sensed. A pressure sensor senses a pressure of the exhaust gas proximate to the pressure mass flow controller. The temperature sensor corrects the exhaust gas flow measurement based upon the pressure sensed.

Abstract: A vehicle exhaust measurement system is provided includes that a conduit having a conduit inlet and a conduit outlet. A make-up air tube is connected to and is in fluid communication with the conduit inlet. The make-up air tube provides make-up air for mixing an exhaust gas. A mixed gas tube is connected to and is in fluid communication with the conduit outlet. The mixed gas tube conveys a mixture of make-up air and exhaust gas to analysis equipment. In the preferred embodiment, the exhaust gas tube extends through an outer wall of the conduit. A mixing plate is arranged in either the conduit or the mixed gas tube with the exhaust gas tube extending to a position adjacent to the mixing plate. The exhaust gas tube conveys the exhaust gas to the mixing plate to mix the exhaust gas and the make-up air at the mixing plate.

Abstract: A vehicle exhaust measurement system is provided includes that a conduit having a conduit inlet and a conduit outlet. A make-up air tube is connected to and is in fluid communication with the conduit inlet. The make-up air tube provides make-up air for mixing an exhaust gas. A mixed gas tube is connected to and is in fluid communication with the conduit outlet. The mixed gas tube conveys a mixture of make-up air and exhaust gas to analysis equipment. In the preferred embodiment, the exhaust gas tube extends through an outer wall of the conduit. A mixing plate is arranged in either the conduit or the mixed gas tube with the exhaust gas tube extending to a position adjacent to the mixing plate. The exhaust gas tube conveys the exhaust gas to the mixing plate to mix the exhaust gas and the make-up air at the mixing plate.

Abstract: A particulate sampler is provided for use in analyzing particulate matter in exhaust gas. The sampler includes a transfer tube assembly including a probe at least partially defining a sample exhaust gas passageway. The transfer tube assembly has a first end portion with an opening for receiving exhaust gas and extends to a second end portion. A mixer receives the second end portion and includes a dilution gas passageway for carrying a dilution gas. The dilution gas passageway is in communication with the sample exhaust gas passageway for introducing the dilution gas to the exhaust gas. A tunnel is connected to the mixer and includes a gas mixing passageway extending a length for homogeneously mixing the gases together. The gas mixing passageway tapers toward the second end portion to ensure that the particulate matter mixes with the gases along the length of the gas mixing passageway without collecting in a recirculating flow area.

Abstract: An exhaust emission analysis system is provided that includes an exhaust and dilution gas source respectively providing exhaust and dilution gases. A dilution unit includes exhaust and dilution gas flow devices, such as mass flow controllers, fluidly connected to the exhaust and dilution gas sources, respectively. The metering device in the mass flow controllers defines a gas flow rate of gas from its respective gas source. The gas flow devices are fluidly connected at a connection that mixes the gases to provide a diluted exhaust gas having an incorrect dilution ratio. A water measurement device such as an analyzer measures the water content of the exhaust gas, preferably subsequent to dilution. A water content dilution signal corresponding to the water content in the exhaust gas is sent from the water measurement device to a control device.