In order to make it possible to accurately analyze particulate matter contained in exhaust gas without making a system large-scale or expensive, the present invention is adapted to include an exhaust gas flow path through which exhaust gas of an internal combustion engine is introduced, a branch flow path that branches from the exhaust gas flow path, a first analyzer that is provided downstream of a branch point of the branch flow path in the exhaust gas flow path and measures particulate matter contained in the exhaust gas, a second analyzer that is provided in the branch flow path and measures the particulate matter contained in the exhaust gas, and a temperature control mechanism that controls the temperature of the first analyzer.

An exhaust gas analysis system is adapted to include an exhaust gas circulation line through which exhaust gas flows, an exhaust gas collection line adapted to collect the exhaust gas from the exhaust gas circulation line and introduce the collected exhaust gas into an exhaust gas analysis device, a continuous analysis line adapted to, separately from the diluted exhaust gas collection line, collect the exhaust gas from the exhaust gas circulation line for continuous analysis, a continuous analyzer provided in the continuous analysis line, and an information processing unit adapted to, on the basis of an analysis result by the continuous analyzer at the time of the collection into the exhaust gas analysis device, determine whether a measurement result of the exhaust gas introduced into the exhaust gas analysis device falls within a preset range, or determine a measurement range used to measure the exhaust gas introduced into the exhaust gas analysis device.

A process dilutes an aerosol by feeding an input aerosol through an inlet pipe surrounded by an annular space to a first mixing stage. An output aerosol leaves purified via an outlet as a particle-free clean gas. The particle-free clean gas is fed to the annular space upstream of the outlet and is mixed with the aerosol. A mixing stage includes an inlet pipe feeding aerosol as inlet aerosol. A downstream purification device purifies outlet aerosol leaving the mixing stage via an outlet pipe to form the particle-free clean gas. A mass flow controller and a pump suction off the outlet aerosol from the outlet pipe. A return line, for the clean gas, leads upstream into the annular space.

A filter made of a sponge material having air permeability and elasticity is interposed between an exhaust port of an exhaust gas sampling unit and a sampling port to thereby close a gap between the exhaust port and the sampling port. In this state, when the exhaust gas sampling unit is suctioned at a constant flow rate, the exhaust gas and the outside air around the exhaust port are taken into the exhaust gas sampling unit from the sampling port. At this time, the flow rate of the outside air taken in through the filter is suppressed by the air-flow resistance of the filter, and therefore the total flow rate of the exhaust gas and the outside air taken into the exhaust gas sampling unit is caused to be less than the suction flow rate, thereby simply and reliably preventing the exhaust gas from leaking out.

Exhaust gas discharged from an exhaust port is taken into an exhaust gas sampling unit together with the surrounding outside air. A leak detection mechanism, which detects the leakage of exhaust gas from a sampling port, includes a temperature sensor including an outside and an inside temperature sensors, and a temperature measuring instrument for measuring a temperature difference between inside and outside temperatures detected by the temperature sensor. A plurality of inside/outside paired temperature sensors is disposed in the circumferential direction of the sampling port. When a leak occurs, the temperature of the inside temperature sensors rises and the temperature difference between the inside and the outer and outside temperature sensors increases, and the temperature measuring instrument detects the leak. When a leak occurs in a portion of the circumferential direction, only the temperature difference of the portion where the leak occurs is increased, and the location of the leak is identified.

The present invention relates to a method for measuring condensable particulate matters formed from exhaust gas of an internal combustion engine, including the steps of sucking exhaust gas from the internal combustion engine; diluting the sucked exhaust gas to simulate it to atmospheric condition; a first measurement step of branching some of the exhaust gas of the atmospheric condition and measuring particulate matters including condensable particulate matters and filterable particulate matters; a second measurement step of branching the rest of the exhaust gas of the atmospheric condition to remove the condensable particulate matters and measuring the particulate matters including only the filterable particulate matters; and comparing the first measurement step and the second measurement step to calculate an amount of the condensable particulate matters in the exhaust gas of the atmospheric condition.

The present claimed invention provides an exhaust gas analysis system using a dilution sampling method with an exhaust gas analysis device that can calculate a measured value such as a concentration of a component to be measured in an exhaust gas with higher accuracy. The exhaust gas analysis device analyzes a diluted exhaust gas, and comprises an analyzing part that measures a component to be measured in the diluted exhaust gas, an introducing path that introduces the diluted exhaust gas into the analyzing part and that has a resistance part, a viscous component concentration determining part that determines a concentration of a viscous component that is in the diluted exhaust gas and that is different from the component to be measured, and a correction part that corrects the measured value measured by the analyzing part in accordance with the concentration of the viscous component.

In order to provide an exhaust gas sampling apparatus that makes it possible to simplify the entire system using a simple structure flow rate control mechanism having a small variable flow rate range as well as making the accuracy of an exhaust gas dilution ratio higher than before, the exhaust gas sampling apparatus is configured as an exhaust gas sampling apparatus that makes a multistage dilution. In addition, the exhaust gas sampling apparatus is configured to, given that a dilution ratio determined by an n-th diluter in a dilution flow path at an n-th stage as a final stage is R, make dilution ratios determined by diluters in dilution flow paths at the respective stages other than the n-th stage as the final stage substantially equal to (R+1).

The present invention is intended that diluted exhaust gas is supplied to a plurality of measurement instruments by a single exhaust gas dilution device to thereby reduce in size an exhaust gas measurement system incorporated with the exhaust gas dilution device and dilute exhaust gas with the same exhaust gas under the same dilution condition in the plurality of measurement instruments.

An engine emissions test system according to the principles of the present disclosure includes a sampling conduit, at least one sample bag, a read circuit, and a fill circuit. The sampling conduit is configured to receive exhaust from an engine. The at least one sample bag is configured to store a sample of exhaust. The read circuit is configured to communicate the stored sample of exhaust between the at least one sample bag and an analyzer. The fill circuit includes a fill gas line configured to provide a fill gas to be mixed with the sample of exhaust. The fill gas line extends between a fill gas source and the read circuit.