A reduction device includes a housing defining an input chamber configured to receive exhaust from a power source, an output chamber, an exhaust channel configured to direct the exhaust from the input chamber to the output chamber, and a longitudinal axis. The reduction device also includes a treatment unit disposed in the exhaust channel and along the longitudinal axis. The treatment unit is configured to at least partly remove pollutant species from the exhaust. The reduction device also includes an attenuation component disposed in the housing and radially outward of the treatment unit. The attenuation component is fluidly connected to the exhaust channel, and is configured to attenuate a range of frequencies corresponding to operation of the power source. Additionally, the exhaust channel prohibits exhaust entering the input chamber from exiting the housing without passing through the treatment unit.

A method of using a burner-based exhaust replication system to generate exhaust that contains nitrogen dioxide (NO.sub.2). An example of such as system is a system used to test automotive exhaust aftertreatment devices. A fluid that decomposes to generate NO.sub.2 as one of its decomposition products is selected. The fluid is heated thereby generating NO.sub.2, with the amount and duration of heating is controlled to result in a desired decomposition extent of NO.sub.2 from the fluid. The fluid is then delivered to an exhaust stream of the system.

A process oxygen analyzer includes a process probe extendible into a flow of process combustion exhaust, the process probe having an oxygen sensor measurement cell. Measurement circuitry is coupled to the oxygen sensor measurement cell and configured to obtain a non-corrected indication of oxygen concentration relative to a combustion process based on an electrical characteristic of the oxygen sensor measurement cell. A controller is operably coupled to the measurement circuitry and is configured to obtain an indication of process pressure and selectively provide a corrected oxygen concentration output based on non-corrected indication of oxygen concentration and the indication of process pressure. A method of providing a process oxygen concentration using a process oxygen analyzer coupled to an industrial combustion process is also disclosed.

An exemplary embodiment may include a control hub configured to receive data from an emissions analyzer and a leak detection camera. The emissions analyzer may detect levels of various gases and relay such information to the control hub. In an exemplary embodiment, the emissions analyzer may purge after every test to ensure longevity and accuracy. A leak detection camera may implement quantifying optical gas imaging in order to continuously monitor for fugitive leaks on a compressor package. If a leak is detected, it may be logged and the user or an operating group may be alerted.

A sensor tube structure includes a sensor housing, a sensor mounted on the sensor housing, an external tube mounted at an end of the sensor housing to enclose the sensor, an inner tube provided to be movable inside the external tube, a drive plate in which a sensor hole into which the sensor is inserted is formed, and is coupled to the inner tube, and an actuator mounted on the sensor housing and selectively moving the drive plate.

An air monitoring system measures tan amount of pollutant in the air. The system includes a plurality of air quality sensor devices arranged within a selected area. Each of the air quality sensor devices is configured to measure air pollutant levels in the selected area, and includes at least one sensor operatively coupled to a controller, wherein the controller is configured to receive a measured input from the at least one sensor. A wireless communication device is coupled to the controller, and is configured to communicate with a central server device.

This collectively manages an operation rate of multiple test facilities, and is an operation rate analysis system that is communicably connected to multiple test facilities that test a specimen as being a vehicle or a part of the vehicle and that analyzes an operation rate of the above-mentioned multiple test facilities, and that comprises an operation information obtaining part that obtains operation information of the above-mentioned multiple test facilities, a setting receiving part that receives a user setting relating to an operation judgment condition to judge whether each of the multiple test facilities is in operation or not, and an operation rate calculating part that calculates the operation rate of each of the multiple test facilities or the operation rate of all of the multiple test facilities from the operation information obtained by the operation information obtaining part based on the operation judgment condition received by the setting receiving part.

A diagnostic system and method that (a) that uses models indicative of both successful firing and skips to determine if cylinders of a skip fire controlled internal combustion engine have successfully fired or successfully skipped and (b) uses filtered exhaust gas pressure readings for detecting faults associated with EGR systems and/or turbocharger systems.

An exhaust aftertreatment system and associated method for purifying an exhaust gas feedstream of a lean-burn or other compression-ignition internal combustion engine is described. An instruction set is executable to determine an engine-out NO2 concentration upstream of an oxidation catalyst and determine a first parameter associated with O2 concentration. A consumption of oxygen in the oxidation catalyst due to oxidation reactions is determined, and a concentration of NO2 generated by the oxidation catalyst is determined based upon the consumption of oxygen in the oxidation catalyst. A concentration of NO2 downstream of the oxidation catalyst is determined. A NO2/NOx ratio in the exhaust gas feedstream downstream of the oxidation catalyst is determined based upon the concentration of NO2 downstream of the oxidation catalyst and the NOx concentration measured by the downstream NOx sensor. The oxidation catalyst is evaluated based upon the NO2/NOx ratio.

A reduction device includes a housing defining an input chamber configured to receive exhaust from a power source, an output chamber, an exhaust channel configured to direct the exhaust from the input chamber to the output chamber, and a longitudinal axis. The reduction device also includes a treatment unit disposed in the exhaust channel and along the longitudinal axis. The treatment unit is configured to at least partly remove pollutant species from the exhaust. The reduction device also includes an attenuation component disposed in the housing and radially outward of the treatment unit. The attenuation component is fluidly connected to the exhaust channel, and is configured to attenuate a range of frequencies corresponding to operation of the power source. Additionally, the exhaust channel prohibits exhaust entering the input chamber from exiting the housing without passing through the treatment unit.