An exhaust purification system includes: a diesel oxidation catalyst (DOC) provided on an exhaust passage of an engine; a diesel particulate filter (DPF) provided on the exhaust passage at a position downstream of the DOC to collect particulate matter contained in exhaust gas; electrodes that detect a capacitance of the DOC; a particulate matter accumulation estimating unit that estimates an amount of particulate matter accumulated in the DPF on the basis of the detected capacitance; and a forced regeneration control unit that injects fuel into the DOC and performs forced regeneration that burns and removes at least the particulate matter accumulated in the DPF when the estimated accumulated particulate matter amount surpasses a predetermined amount.

A method is provided for determining exhaust mass flow through a diesel particulate filter (DPF) in an engine arrangement including an engine and an exhaust after treatment system (EATS) comprising the DPF. The method comprises determining soot loading and soot distribution in the DPF, measuring pressure drop over the DPF, measuring pressure in the DPF, measuring temperature in the DPF, and determining exhaust mass flow through the DPF as a function of the measured pressure drop, the measured pressure, the measured temperature, and the soot loading and soot distribution. An arrangement is also provided for determining exhaust mass flow through a diesel particulate filter. A method for controlling one or more engine components, and an engine, are also provided.

A level sensor assembly (10) for measuring physical properties indicative of a quality of a urea solution (AdBlue/DEF), where at least a portion of said level sensor assembly (10) is inserted in a tank (50), said level sensor assembly (10) comprises a header unit (12) mounted in an aperture of the tank (50); heating tubes (20) inserted in the tank for heating/thawing the urea solution in the tank (50) and one or more tubes (22) for suction of urea solution from the tank (50), said tubes (20,22) being connected to the header unit (12); and a level sensor (24,26) for measuring level of urea solution in the tank (50). Further, a detachable UQS sensor (30) is installed in the header unit (12), said UQS sensor (30) being at least partly submerged in a liquid pool (32) of urea solution in the header unit (12), and the liquid pool (32) in the header unit (12) comprises a compressible and/or expanding bottom (34).

The sensor includes a filter member including cells that trap PM in exhaust gas; electrode members arranged to face each other with the cell interposed and forming a capacitor, an electric heater that executes, when an amount of PM has accumulated in the cells, filter regeneration of heating the cells to combust and remove the PM, a storage unit that stores a reference reduction amount, which is an electrostatic capacitance reduction amount between the electrode members in a case where the filter regeneration is executed in a state where the PM is not flowing into the filter member, and estimation units that estimate a PM amount based on (a) an actual electrostatic capacitance change amount between the electrode members during a regeneration interval period, and (b) a difference between an actual electrostatic capacitance reduction amount between the electrode members and the reference reduction amount during a filter regeneration period.

An aftertreatment system configured to reduce constituents of an exhaust gas produced by an engine comprises an aftertreatment component and an optical assembly. The optical assembly comprises an optical emitter configured to emit light onto a face of the aftertreatment component, and an optical detector configured to detect light reflected from the face of the aftertreatment component. A controller is configured to determine at least one of an amount of NOx gases or an amount of ammonia on the face of the aftertreatment component based on an optical parameter of the detected light that has reflected from the face of the aftertreatment component.

A process for detecting reductant deposits includes accessing data indicative of signal output from a radiofrequency sensor positioned proximate a decomposition reactor tube; comparing the data indicative of signal output from the radiofrequency sensor to a deposit formation threshold; and activating a deposit mitigation process responsive to the data indicative of signal output from the radiofrequency sensor exceeding the deposit formation threshold.

An exhaust gas purification device includes a diesel particulate filter (DPF) for capturing particulate matter (PM) in an exhaust gas, a selective catalytic reduction (SCR) device for reducing NOx in the exhaust gas, detecting units for detecting the DPF electrostatic capacity, an estimating unit for estimating the inside temperature of the DPF based on the electrostatic capacity, and a controlling unit for executing forced DPF regeneration. A lower limit temperature is defined as a temperature to trigger PM combustion, and an upper limit temperature is defined as a temperature to avoid filter erosion. The controlling unit executes the forced regeneration with an amount of fuel supplied for causing the inside temperature to reach the lower limit temperature, when the inside temperature is at or above the SCR activation temperature, and executes the forced regeneration with another amount of fuel supplied for causing the inside temperature to reach the upper limit temperature, when the inside temperature is below the SCR activation temperature.

A heater is provided that includes at least one resistive heating element having a material with a non-monotonic resistivity vs. temperature profile and exhibiting a negative dR/dT characteristic over a predetermined operating temperature range along the profile. The heater can include a plurality of circuits disposed in a fluid path to heat fluid flow.

A method of using a radio frequency sensor for determining an estimate of soot load in a diesel particulate filter is disclosed, The method comprises: receiving a first mean attenuation value derived from attenuation values for each of a first plurality of radio frequencies within a first band of radio frequencies detected by the radio frequency sensor; and receiving first standard deviation data for the mean attenuation value relating to the first plurality of radio frequencies within the first band of radio frequencies. The method further comprises: determining whether the standard deviation data exceeds a standard deviation threshold, In the event that the standard deviation data does not exceed a standard deviation threshold, the method uses the first mean attenuation value to infer a value for soot load in the diesel particulate filter, in the event that the standard deviation data exceeds a standard deviation threshold, the method comprises: receiving a second mean attenuation value derived from attenuation values for each of a second plurality of radio frequencies within a. second band of radio frequencies; and receiving second standard deviation data relating to the mean attenuation value for a second plurality of radio frequencies within the second band of radio frequencies detected by the radio frequency sensor, In the event that the second standard deviation data does not exceed the standard deviation threshold, the method uses the second mean attenuation value to infer the value for soot load in the diesel particulate filter.

A device that includes a conduit, a first window, a second window, a first catalyzed layer, a second catalyzed layer, an optical source, and an optical detector is disclosed. The conduit may be configured to receive an exhaust gas. The first catalyzed layer may be disposed on the first window and the second catalyzed layer may be disposed on the second window. The first catalyzed layer and the second catalyzed layer may be configured to cause a reaction with soot in the exhaust gas at an activation temperature to reduce accumulation of the soot on the first window and the second window. The optical source may be configured to emit a beam of light into the conduit through the first window. The optical detector may be configured to receive at least a portion of the beam of light through the second window.