Abstract: A method for controlling a particulate matter sensor heater is provided. The method includes operating the heater to burn-off soot accumulated on the sensor; and adjusting the heater level based on sensor output generated during the heater operation. In this way, improved heater control can be achieved using the sensor output already available.

Abstract: In a PM detection sensor with a sensor element having a pair of detection electrodes formed on a substrate, quantity of PM accumulated in the detection electrode is calculated on the basis of a resistance change between the detection electrodes. A series circuit composed of a temperature detection resistance and a capacitor connected in series is formed on a conductive path in the sensor element. A microcomputer in an ECU instructs a power source to supply a DC voltage to the resistance and the capacitor to make a first state in which no current flows in the resistance when a quantity of PM accumulated in the sensor element is detected. The microcomputer instructs the power source to supply an AC voltage to the resistance and the capacitor to make a second state in which a current flows in the resistance when a temperature of the sensor element is detected.

Abstract: Provided are a method and an apparatus of controlling a flow rate of a primary recirculating exhaust gas in an oxyfuel combustion boiler, capable of realizing a stable combustion by a burner in oxyfuel combustion. Weight ratio of flow rate of primary recirculating exhaust gas [ton/h] to amount of pulverized coal from a mill [ton/h] is defined as G/C, and the flow rate of primary recirculating exhaust gas is controlled so that the G/C falls within a given range.

Abstract: Provided are a method and an apparatus of controlling exhaust gas in an oxyfuel combustion boiler which can attain stable combustion of the boiler while an amount of unburned combustibles and a NOx density in exhaust gas are maintained in their allowable ranges. A rate of supply of directly supplied oxygen to burners 6 to a total amount of oxygen produced by an air separation unit 18 is regulated in an operating range where the NOx density in the exhaust gas is below a NOx limit value and the amount of unburned combustibles in the exhaust gas is blow an unburned combustible limit value to thereby attain stable combustion of the oxyfuel combustion boiler.

Abstract: The present invention discloses a combustor system and method of measuring impurities in the combustion system. The combustion system includes an up-stream fuel injection point; a down-stream turbine combustor; a flame zone in the turbine combustor comprising a plurality of axial sub-zones; an optical port assembly configured to obtain a non-axial, direct, optical view of at least one of the plurality of axial sub-zones, and an impurity detection system in optical communication with the optical port assembly.

Abstract: Disclosed is a particulate matter measurement device that continuously measures changes in a mass of particulate matters contained in an exhaust gas under dynamic operating conditions. The device dilutes and separates the flow of exhaust gas while an engine is operating. The particulate matters contained in one of the exhaust gas streams are collected by a collection filter to measure the mass and the remainder is measured by a mass-related value measurement. Then, time series change data for the mass of the particulate matter are found based on correlations of the individual measured data. With this arrangement, the flow volume of the dilute exhaust gas that passes through the collection filter and the flow volume of the dilute exhaust gas that is introduced into the mass-related value measurement device are ensured by adjusting the flow volume of the diluting gas that dilutes the exhaust gas.

Abstract: A control method for monitoring a soot sensor of an exhaust treatment system is provided. The control method includes: determining when regeneration has completed; comparing soot sensor data to an estimated soot data based on the determining; and generating a message based on the comparing.

Abstract: What is disclosed is a system and method for testing a motorized vehicle's exhaust emissions in a non-controlled emissions testing environment. In one embodiment, the present system comprises a toll collection structure having a sensor for obtaining information about a registered owner of a motor vehicle and about the motor vehicle itself, as the vehicle travels on a lane which passes through the structure. At least one emissions detector, which is fixed to the toll collection structure, performs an emissions test on the vehicle by analyzing an exhaust plume emitted by the vehicle. Speed/acceleration of the vehicle is also measured. In various embodiments hereof, the emissions detector comprises a combination of dispersive or non-dispersive infrared detector and a dispersive or non-dispersive ultraviolet detector. Emissions data collected is automatically compared to emissions standards and an authority is notified if that the vehicle does not meet those standards. Various embodiments are disclosed.

Abstract: An amount of particulate matter accumulated in a particulate filter of an exhaust system is estimated by preloading a memory location with a plurality of hybrid models. Each hybrid model estimates an amount of particulate matter accumulated in the particulate filter between a pair of operating points. An estimated amount of particulate matter accumulated in the particulate filter is stored in the memory location for each hybrid model. Each hybrid model is ranked based on estimation accuracy during operating conditions and the highest ranked hybrid model is selected. The estimated amount of particulate matter accumulated in the particulate filter corresponding to the highest ranked hybrid model is added to the soot estimation value stored in the memory location that corresponds to a ranked hybrid model to provide a soot estimation value of a cumulative estimated amount of particulate matter contained in the particulate filter for the ranked hybrid model.

Abstract: A system to measure a parameter of a particulate laden gas flow may include a conduit enclosed by a boundary wall directing the particulate laden gas flow and a sensor configured to measure the parameter. The system may also include an annular averaging chamber extending radially outwardly from the conduit. The averaging chamber may be positioned such that the sensor is fluidly coupled to the conduit through the averaging chamber. The system may further include a porous element extending around the conduit. The porous element may be positioned such that the averaging chamber is fluidly coupled to the conduit through the porous element.

Abstract: A soot emission estimation method and arrangement for a diesel engine estimates the amount of soot generated in a combustion chamber of the diesel engine. The method includes providing values for speed and load; providing a base soot value from an engine speed-load resolved reference soot map; defining and providing emission influencing input parameters; calculating a deviation between at least one emission influencing input parameter and a speed-load resolved reference value for the at least one emission influencing input parameter; multiplying the calculated deviation with an individual value from an individual speed-load resolved weight map for the at least one emission influencing input parameter, thereby creating an emission influencing input parameter related correction for the at least one emission influencing input parameter; adding and summarizing the at least one emission influencing input parameter related correction to the base soot value and thereby obtaining an estimated soot mass flow value.

Abstract: A sensor element for determining a gas component or particles in a measuring gas, having a first and a second measuring electrode, the measuring electrodes being developed as interdigital electrodes having a row of intermeshing branches as well as a main conductor each, to which the branches are connected in an electrically conducting manner; and the branches of the interdigital electrodes being aligned essentially in parallel to a longitudinal axis of the sensor element.

Abstract: A sensor control device is adapted for an engine including an exhaust passage along which an exhaust purification catalyst and a particulate matter detection sensor are disposed. The exhaust purification catalyst 14 purifies a given gas component included in exhaust gas. The particulate matter detection sensor includes an attaching part, to which conductive PM included in exhaust gas is attached, PM including more than one component. The particulate matter detection sensor outputs a detection signal that is in accordance with a weight of PM attached to the attaching part. The particulate matter detection sensor includes an upstream detection sensor that is disposed on an upstream side of the exhaust purification catalyst in a flow direction of exhaust gas. The device includes a particle number calculation unit that calculates a particle number of PM in exhaust gas based on the detection signal outputted by the upstream detection sensor.

Abstract: A soot sensor includes a soot sensor including a first element on a first surface of the soot sensor. A soot sensing system may include a soot sensor and circuitry electrically coupled to the first element of the soot sensor. The circuitry is configured to determine an amount of soot accumulated on the first element and to control heating of the first element in response to the soot accumulation.

Abstract: A particulate matter sensor includes a ceramic rod, a first metal layer deposited on the ceramic rod, a ceramic layer deposited on the first metal layer, and a second metal layer deposited on the ceramic layer. The first metal layer serves as a source electrode, and the second metal layer serves as a detection electrode. In another embodiment, a particulate matter sensor includes a metal rod, a ceramic sheet deposited or wrapped around the ceramic rod, and a metal layer deposited on the ceramic layer or sheet. The metal rod serves as a source electrode, and the second metal layer serves as a detection electrode.

Abstract: A new apparatus for monitoring fine particle concentration in an exhaust system of a combustion engine has a part that extends into the exhaust system, and a housing that includes structure that attaches and seals the apparatus to the exhaust system through a single opening in a wall of the exhaust system. A gas inlet in the housing provides a measurement flow into a particle measurement sensor inside the housing. At least a fraction of the particles entering the particle measurement sensor are charged, and at least a fraction of the current carried by the charged particles are detected. A gas outlet in the housing carries the measurement flow away from the particle measurement sensor. The structure that attaches the apparatus to the exhaust system has one electrical connector that provides power to the sensor, and another electrical connector that transmits the electrical signal created by the sensor.

Abstract: An exhaust aftertreatment system having a particulate filter is monitored by monitoring a particulate filter regeneration event and detecting an associated regeneration period. The particulate filter regeneration period is compared to a preferred event window. A fault is detected when the monitored particulate filter regeneration period extends beyond the preferred event window.

Abstract: Methods of characterizing and measuring particulate accumulation in a family of particulate filters (10) are disclosed. The disclosure can be applied to diesel, gasoline and natural gas fueled engines, fluid streams bearing dust, and chemical and biological substances such as may be found in laboratory fluids, for example, air. In one embodiment, the disclosure is directed to measuring diesel particulate accumulation in a family of diesel particulate filters. The methods include measuring calibration complex terahertz transmission spectra (PC(f)) of at least a portion (17) of at least one particulate or diesel particulate filter in the family for different known particulate or diesel particulate amounts (ADP). The method also involves performing a partial least squares (PLS) analysis on the calibration complex terahertz transmission spectra to establish a calibration relationship between the complex terahertz transmission spectra and the particulate or diesel particulate amounts.

Abstract: A method of detecting ash in an exhaust particulate filter system for an internal combustion engine includes transmitting electromagnetic energy through an exhaust particulate filter containing soot and ash, and sensing a strength of the transmitted electromagnetic energy after having been attenuated in response to the soot. The method further includes electronically storing a filter monitoring history responsive to a difference between the transmitted strength and the sensed strength of the electromagnetic energy, and detecting an amount of the ash based at least in part upon a pattern of electromagnetic energy attenuation defined by the stored filter monitoring history. An exhaust particulate filter system for implementing related methodology includes a microprocessor configured to determine a value indicative of an amount of ash contained within an exhaust particulate filter responsive to a pattern of electromagnetic energy attenuation defined by a stored filter monitoring history.

Abstract: A particulate detection system (1, 2, 3) detects the quantity of particulates S contained in exhaust gas EG discharged from an internal combustion engine ENG and flowing through an exhaust pipe EP. The system (1, 2, 3) includes a detection section (10) attached to the exhaust pipe EP; and a drive processing circuit (201) electrically connected to the detection section (10), driving the detection section (10), and detecting and processing a signal Is from the detection section 10. The drive processing circuit (201) includes drive start delay means (S2, S3, S11, S12, S13, S22, S23) for delaying start of the drive of the detection section (10) until a start condition determined by the drive processing circuit (201) is satisfied after startup of the internal combustion engine ENG.

Abstract: An object of the present invention is to provide a particulate matter detecting apparatus for an internal combustion engine that can maintain an appropriate balance between reduction in time required for one detecting sequence and limiting of power consumption of a heater for sensor reset. The particulate matter detecting apparatus for an internal combustion engine includes: a sensor disposed at an exhaust passage of an internal combustion engine, the sensor including a pair of electrodes for trapping particulate matter; voltage applying means for applying voltage across the electrodes; discharge amount index acquiring means for acquiring a predetermined index associated with a discharge amount of the particulate matter; and voltage adjusting means for adjusting the voltage to be applied across the electrodes based on the index acquired by the discharge amount index acquiring means such that the voltage is lower when the discharge amount is large than when the discharge amount is small.

Abstract: A particulate matter detection device including a detection device main body which has one end provided with a through hole a pair of electrodes embedded in a wall through which the through hole is formed, and covered with a dielectric material; wires extending from the electrodes to the other end of the main body; and a ground electrode provided at a position sandwiched between the wires. The device can electrically adsorb, on the wall surface of the through hole, a charged particle in a fluid flowing into the through hole, or a particle charged by electric discharge caused in the through hole by applying a voltage across the pair of electrodes. The device can measure the changes of the electric properties of the wall through which the through hole is formed, thereby detecting particles adsorbed on the wall surface of the through hole.

Abstract: Embodiments of a particle sensor are provided. In one example, a particle sensor for an exhaust system comprises at least two inlet openings for an exhaust-gas flow of the exhaust system, wherein the inlet openings are of different sizes, and at least two sensor elements, wherein in each case one sensor element is arranged downstream of one inlet opening. In this way, the relative proportion of different-sized particles within the exhaust-gas flow may be determined.

Abstract: A detection apparatus includes a particulate matter (PM) detection unit, a temperature detection unit, and a correction unit. The PM detection unit includes an insulator, a pair of electrodes, and a detector. The insulator is disposed in an exhaust path of an internal combustion engine through which an exhaust gas flows. The pair of electrodes are arranged in contact with at least a part of the insulator. The detector detects a PM detection value which is a value correlated to an amount of PM in the exhaust gas. The temperature detection unit detects at least one of an exhaust temperature of the exhaust gas passing through the PM detection unit and an insulator temperature of the insulator. The correction unit corrects the PM detection value detected by the PM detection unit based on at least one of the exhaust temperature and the insulator temperature.

Abstract: A particulate estimation system is configured for estimating a mass of particulate matter accumulated in a particulate filter of an exhaust system. The system includes a memory device, an interface, and a controller. The memory device stores a plurality of modules. Each of the plurality of modules is configured to uniquely estimate an amount of the particulate matter accumulated within the particulate filter over a period of time. The interface receives a plurality of input signals. The plurality of input signals correspond to a plurality of modules that are stored in the memory device. The controller derives a hybrid model based on the input signals. The hybrid model is configured to provide an output that is an estimation of the amount of particulate matter accumulated within the particulate filter over the period of time as a function of the plurality of input signals.

Abstract: Providing a PM emission amount estimation device for the diesel engine wherein the accuracy of the correction in correcting the basic level of the PM emission amount by use of the PM emission amount estimation map can be enhanced; and, the PM emission amount particularly during the transient state of the engine operation condition can be accurately computed so as to estimate, with high precision, the PM emission amount and the PM emission accumulated-amount (integrated amount) during the whole engine operation conditions including the transient state as well as the steady state.

Abstract: In a PM detection sensor S having a PM sensor element 1 installed in an exhaust-gas pipe of an engine E/G, PM detection electrodes are placed in detection spaces in slits, respectively, formed in an insulation substrate. In the insulation substrate, one slit is embedded between an electric field generating electrode and a common electric field generating electrode. The other slit is embedded between an electric field generating electrode and the common electric field generating electrode. The same magnitude of an electric field is generated between the detection spaces when electric power is supplied to the electric field generating electrodes. An average value of sensor outputs transferred from the PM detection electrode is used as a sensor output of the PM sensor element.

Abstract: In a method for determining an NO2 concentration and/or a concentration ratio of NO2 and NO in an exhaust tract of a combustion device, such as an internal combustion engine, an NOx sensor that is sensitive with respect to NO2 and NO is utilized, which provides a NOx output signal correlating with an NOx concentration representing the sum of the concentrations of NO2 and NO. In order to determine the NO2 concentration and/or the concentration ratio of NO2 and NO, the NOx output signal of a first NOx sensor, which is arranged upstream of an exhaust gas treatment element arranged in the exhaust tract and having the capability of converting NO to NO2 and/or converting NO2 to NO, is compared to the NOx output signal of a second NOx sensor, which is disposed downstream of the exhaust gas treatment element.

Abstract: A system includes an internal combustion engine producing an exhaust stream, a particulate filtering device that treats the exhaust stream, a particulate sensor operatively coupled to the exhaust stream at a position downstream of the particulate filtering device, and a temperature sensor operatively coupled to the exhaust stream. The system includes a controller that interprets a particulate sensor particulate stability condition, interprets a particulate sensor input value and a particulate sensor temperature, compensates the particulate sensor input value in response to the particulate sensor temperature, and filters the compensated particulate sensor input value. The controller determines a soot accumulation value in response to the filtered compensated particulate sensor input value, interprets a diagnostic enable condition, and determines a particulate filter diagnostic value in response to the active diagnostic enable condition and the soot accumulation value.

Abstract: A particulate matter detection device 100 includes a first electrode 1 whose one surface is covered with an inter-electrode dielectric material 4; a second electrode 2 disposed on the side of the one surface of the first electrode 1, to perform the discharge of electricity by a voltage applied between the first electrode 1 and the second electrode; and a pair of measurement electrodes 5, 15 disposed on the surface of the inter-electrode dielectric material 4 so as to face each other; characteristic measurement means 3 for measuring electric characteristics between the pair of measurement electrodes 5 and 15; and particulate matter amount calculation means 13 for obtaining the amount of the particulate matter 11 collected by the surface of the inter-electrode dielectric material 4, based on the change amount of the electric characteristics.

Abstract: In a PM detection sensor, a gas introduction hole is formed in a cover unit which surrounds a PM detection element. The gas introduction hole faces a detection part having detection electrodes of a comb structure. A projected part generated when an opening part of the gas introduction hole is projected on the detection part is within an inside area of the detection part. The projected area of the opening part of the gas introduction hole is positioned within the inside area having a uniform electric field intensity between the detection electrodes. The target detection gas is directly introduced through the gas introduction hole to the area having the uniform electric field intensity generated on the detection part. PM contained in the target detection gas is captured and accumulated on the area having the uniform electric field intensity but not on the area having non-uniform electric field intensity.

Abstract: A shielding part is formed on a detection part in a particulate matter detection element. The detection part has a pair of detection electrodes formed in a comb structure. A shielding layer is made of heat insulating material and formed on the detection part in order to shield a predetermined area having non-uniform electric field intensity. An area having uniform electric field intensity on the detection part is exposed only to exhaust gas as target detection gas when a predetermined voltage is supplied between the detection electrodes in order to detect electric characteristics of the detection part. This structure prevents the area other than the area having the uniform electric field intensity on the detection part from being exposed to the exhaust gas.

Abstract: A particulate matter detection element includes a capacitance component disposed in parallel with a detected resistance RSEN. A direct current-power source that supplies a direct current (IDC) for particulate matter detection, and an alternating-current power source that supplies an alternating current (IAC) for disconnection detection are provided.

Abstract: An electrode assembly for a particulate matter sensor in a gas environment. The electrode assembly includes an insulating tube, a conductor, and a positioning structure. The insulating tube has an outer surface and defines an interior cavity with an interior surface. The conductor is disposed within the interior cavity of the insulating tube. The conductor is electrically coupled to an electrode at a first end of the insulating tube and includes a contact portion at a second end of the insulating tube for connection to an external conductor. The positioning structure is coupled to the conductor. The positioning structure mechanically supports the conductor at a distance from the interior surface of the insulating tube to at least partially define an air dielectric gap at approximately a heater location corresponding to a heater.

Abstract: Provided is a system for determining a number of particles, which has a simplified and compact structure as well as a reduced cost.

Abstract: A metal compound (50) able to trap a sulfur component in exhaust gas is arranged in a flow path of the exhaust gas, a property of the metal compound (50) changing along with an increase of the amount of sulfur component trapped at the metal compound (50) is measured, and the cumulative value of the amount of SOX actually contained in the exhaust gas is calculated from the measured property. On the other hand, the assumed cumulative value of the amount of SOX, assumed to be contained in the exhaust gas when assuming that fuel or oil of a sulfur concentration assumed in advance is used, is calculated. It is judged if fuel or oil with a high sulfur concentration is being used from the actual cumulative value of the amount of SOX and the assumed cumulative value of the amount of SOX.

Abstract: A particulate matter sensor includes a ceramic rod, a first metal layer deposited on the ceramic rod, a ceramic layer deposited on the first metal layer, and a second metal layer deposited on the ceramic layer. The first metal layer serves as a source electrode, and the second metal layer serves as a detection electrode. In another embodiment, a particulate matter sensor includes a metal rod, a ceramic sheet deposited or wrapped around the ceramic rod, and a metal layer deposited on the ceramic layer or sheet. The metal rod serves as a source electrode, and the second metal layer serves as a detection electrode.

Abstract: A system for improving operation of an engine having a particulate matter sensor is presented. The system may be used to improve engine operation during cold starts especially under conditions where water vapor or entrained water droplets are present in vehicle exhaust gases. In one embodiment, an engine controller that activates a heater of an exhaust gas sensor after an output of a particulate matter sensor exceeds a threshold value after an engine is started.

Abstract: A sensor, particularly an impedance sensor, for example a soot sensor, is provided which has two mutually electrically insulated electrodes, wherein at least one external electrode is formed from a composite of metal and inorganic oxide as a film pattern having a film thickness of 0.5 to 20 ?m. The trace width of the film pattern and the spacing between the traces is 5 to 70 ?m and the border region around the conductor trace edge varies less than 10 ?m. Both electrodes can be arranged adjacent to each other as a film pattern in a plane. Preferably, the sensor has a heater. For mass production, electrodes are produced as a film pattern having a film thickness of 0.5 to 20 ?m on electrically insulating oxide bases and, following full-surface imprinting of a metal powder and oxide-containing paste, the electrodes are structured particularly accurately as traces from the printed film. In particular, the film thickness of the printed film is reduced.

Abstract: A particulate matter sensor includes a particulate matter detection filter having a volumetric soot storage capacity smaller than the volumetric soot storage capacity of a diesel particulate filter, and a differential pressure measuring part measuring a differential pressure between an inlet and an outlet of the particulate matter detection filter.

Abstract: A particulate matter detection device of the present invention includes a plate-like element base material, and a pair of measurement electrodes arranged in the element base material, each of the measurement electrodes is a combteeth-like electrode including a plurality of planarly arranged combteeth portions, and a comb spine portion which connects the plurality of combteeth portions of each of the measurement electrodes to one another at one end of each of the plurality of combteeth portions, the combteeth portions of the measurement electrodes are arranged to engage with each other with a space being left therebetween, and the comb spine portion of at least one of the measurement electrodes is covered with a comb spine covering portion made of a dielectric material.

Abstract: A sensor controller is for a particulate matter detection sensor that includes a pair of opposed electrodes spaced from each other and disposed on an attachment portion. The sensor controller includes a calculation portion configured to calculate an amount of particulate matter attached to the particulate matter detection sensor based on a detection value from the particulate matter detection sensor, and a determination portion configured to determine whether water exists in the exhaust passage based on the detection value. Thus, it is possible to accurately determine whether water exists in the exhaust passage.

Abstract: In a gas analyzer 3 and a gas analyzing system 100 adapted to introduce and analyze a part of a measurement target gas flowing through a measurement target gas flow passage 12, in order to ensure accuracy in controlling the measurement target gas flowing through the measurement target gas flow passage 12 and accuracy in its own and other measurements, there are provided an object measurement device 35 adapted to acquire a part of the measurement target gas introduced from the measurement target gas flow passage 12 so as to measure a quantity etc. of a measurement object contained in the measurement target gas, an acquired gas flow rate measurement device 34 adapted to measure a flow rate of the measurement target gas acquired by the object measurement device 35, and a gas supply device 36 adapted to supply another gas of a flow rate equal to the gas flow rate measured by the acquired gas flow rate measurement device 34 to a portion downstream of a shunt point in the measurement target gas flow passage 12.

Abstract: A particulate matter detector of the present invention has an electrode portion, a signal measuring portion, and a calculation portion and further has a measurement signal memory portion for memorizing the values of the measurement signal measured by the signal measuring portion, a signal judgement portion for judging the necessity of correction by comparing a calculated amount of change with a value of a background signal noise after calculating an amount of change between values of the consecutive measurement signals of 10 or less samples memorized by the measurement signal memory portion, and a correction portion for correcting the value of the measurement signal, if the calculated amount of the change shows a decrease of at least twice the value of the background signal noise, by adding the decrease value to the value of the measurement signal where the decrease is confirmed.

Abstract: A method for operating a particle sensor (10). The particle sensor (10) has at least two inter-digital electrodes (12, 13) which engage one in the other and to which a sensor voltage U(IDE) (21) is applied in order to determine loading of the particle sensor (10) with soot particles (16). A sensor current I(IDE) (31) across the electrodes (12, 13) is measured and evaluated. In order to remove the loading with soot, a heating element (14) heats the particle sensor (10) in a regeneration phase. The method characterized in that the sensor current I(IDE) (31) is determined, and a shunt diagnosis of the particle sensor (10) is carried out in accordance with the measured sensor current I(IDE) (31).

Abstract: A gas sensor is capable of detecting a concentration of PM contained in an exhaust gas emitted from a diesel engine. The gas sensor is comprised of a ceramic substrate and detection parts which are formed on the ceramic substrate with resistance parts. A resistance value of each of the resistance parts is changed on the basis of the quantity of conductive particulate matter captured by and accumulated on the detection parts. The detection parts have a different detection range. A part of the detection range of each of the detection parts is overlapped together. The concentration of PM contained in the target detection gas is detected on the basis of the change of the resistance value of the resistance parts.

Abstract: Provided is a method of diagnosing regeneration failure of an exhaust emission control device including filter regenerating means for forcibly heating a particulate filter 13 so as to burn off captured particulates. An exhaust flow rate to the particulate filter 13 and a differential pressure between entry and exit sides of the particulate filter 13 are obtained to calculate a gradient of change in the differential pressure relative to change in the exhaust flow rate. The calculated gradient is compared with a predetermined reference gradient to diagnose the particulate filter 13 as having regeneration failure when the calculated gradient exceeds the reference gradient.

Abstract: A method and kit for determining the effectiveness of an exhaust filter. The method may involve exposing an indicator to an exhaust stream of a engine downstream of the exhaust filter, visually comparing the indicator against test samples, and assigning a level of exhaust filter effectiveness based on the comparison. The method may also involve restricting the exhaust stream, diverting a test stream of exhaust from the exhaust stream, and exposing the indicator to the test stream. The kit may include a collector having a housing defining a flow passage configured to transmit a test stream of exhaust from a engine and a restrictor having a orifice plate configured to restrict an exhaust stream from which the test stream is diverted.

Abstract: A particulate matter sensor is provided for sensing particulate matter present in exhaust gases in a conduit. The particulate matter sensor includes a sensing element with a sensing face which extends into the exhaust conduit and provides a signal indicative of the amount of particulate matter detected in the exhaust conduit. An inner shield is provided to surround the sensing face and includes an inner shield inlet for admitting exhaust gases therein to be sensed. An outer shield surrounds a portion of the inner shield and defines an outer shield chamber extending axially beyond the inner shield. The outer shield has an outer shield inlet passage to receive exhaust gasses from the conduit. Exhaust gases enter the inner shield from the outer shield chamber through the inner shield inlet.

Abstract: A process for monitoring a conversion capacity of a particulate filter arranged in an exhaust gas duct of an internal combustion engine to oxidize nitrogen monoxide to nitrogen dioxide over a catalytic coating includes determining a flow resistance of the particulate filter and setting a temperature of the exhaust gas upstream of the particulate filter. A threshold for a change in the flow resistance of the particulate filter is defined. The monitoring process determines that inadequate conversion capacity of the catalytic coating of the particulate filter is reached when a change in the flow resistance of the particulate filter does not reach the defined threshold within a given period of time.