摘要:
A catalytic converter has a carrier structure and a catalytically active coating adhering to the carrier structure, and is disposed downstream of an internal combustion engine of a motor vehicle for cleaning exhaust gas. A method for functional monitoring of the catalytic converter includes determining a temperature of the catalytically active coating and/or of the structure of the catalytic converter at least at one location. A temperature of the exhaust gas is determined upstream of the at least one location of the catalytic converter. At least first derivatives over time of both temperature values are formed. A difference of the derivatives over time is formed. An instant after a start of the engine at which the difference changes its sign is ascertained. An apparatus for functional monitoring of the catalytic converter includes at least one measuring sensor for measuring a temperature of the carrier structure and/or of the catalytically active coating. At least one device determines an exhaust gas temperature. A differentiation circuit forms derivatives over time of the measured or determined temperatures. A subtraction circuit forms a difference between the two derivatives over time. A comparison circuit ascertains an instant at which the difference changes its sign.
摘要:
A honeycomb body includes an axis, a jacket tube being conical relative to the axis, and a configuration being fitted in the jacket tube. The configuration includes at least one stack being wound about the axis in an involute. The stack has a plurality of sheet metal layers being layered on one another. The layers include a plurality of corrugated layers. Each of the layers has a circular ring segment shape being defined by an outer arc being approximately circular relative to a center point and an approximately circular inner arc being concentric with the outer arc and being disposed between the outer arc and the center point. Each of the corrugated layers has corrugations being oriented approximately radially relative to the center point. The corrugations have associated corrugation heights. The respective corrugation heights on each of the arcs is in a given ratio, and the arcs having lengths in a ratio being approximately equal to the given ratio.
摘要:
A honeycomb body includes an axis along which a flow of fluid is to be conducted through the honeycomb body. At least two oppositely disposed end surfaces define the honeycomb body along the axis. An internal structure for conducting an electric current for heating is formed of at least one sheet-metal layer. Metal support configurations each support the internal structure at a respective one of the end surfaces. An electric insulation is disposed between the internal structure and the support configuration. A method for producing an electrically heatable honeycomb body includes producing at least one approximately rectangular sheet-metal layer having two opposed end edges being aligned approximately perpendicularly to an axis. Each end edge is encompassed with a folded joint having a ceramic layer resting on the at least one sheet-metal layer, to form support configurations. The sheet-metal layer and the folded joints are corrugated at obtuse angles preferably being approximately perpendicularly to the axis. The sheet-metal layer including the folded joints are layered in layers and the layers are wound about the axis. The support configurations are mounted in jacket tubes. Force-locking connections are produced in the support configurations between the layers formed with the folded joints.
摘要:
A metal honeycomb body is disposed within a jacket member. At least partly structured sheet-metal layers are wrapped around one another and extend alternatingly back and forth in a curved, preferably involute, fashion between an outer annular region and an inner annular region of the honeycomb body. The sheet-metal layers form loops. At least three reversal lines are defined in the outer annular region, and the sheet-metal layers are intertwined about these reversal lines. A method for producing the honeycomb body includes the following steps: forming or winding a multi-layer hollow coil from at least one sheet-metal strip which has at least partial structuring; deforming the multi-layer hollow coil from the outside thereof towards the inside at at least three lines such that the at least one sheet-metal strip extends in loops between outer and inner reversal lines; and compacting the resulting deformed multi-layer structure about the inner reversal lines by rotationally intertwining the loops formed by the folded sheet-metal layers in a given direction.
摘要:
A method for monitoring the status of a catalytic converter through which a catalyzable fluid, particularly an exhaust gas from an internal combustion engine, flows along a flow direction from an inlet end to an outlet end, includes measuring the temperature of the catalytic converter along the flow direction continuously or at a plurality of measurement points along the flow direction forming a mean temperature value. The temperature of the catalytic converter is measured at least at one measurement point forming an associated local temperature value. The mean temperature value is compared with the local temperature value for deriving a statement as to the status of the catalytic converter. An assembly for monitoring the status of a catalytic converter through which a catalyzable fluid can flow along a flow direction from an inlet end to an outlet end of the catalytic converter includes a first temperature measuring sensor including a length of wire having a temperature-variable electrical resistance and being coupled to the catalytic converter along the flow direction, and at least one second temperature measuring sensor being coupled to the catalytic converter at a measuring point.
摘要:
An internal combustion engine has an engine control for processing a number of measured values received over measurement lines, converting the measured values into control data for operating the engine and carrying the control data over engine feed lines to the engine, for instance for controlling at least one of fuel injection, air delivery and ignition with the control data. A method for controlling the internal combustion engine includes directly measuring a temperature of walls or structures of a catalytic converter disposed downstream of the engine, supplying a value of the temperature to the engine control over at least one data line, processing the value of the temperature in the engine control along with other measured values and using the processed value to control the engine. An apparatus for controlling the engine and for monitoring the temperature of the catalytic converter includes at least one temperature sensor integrated on or in walls or structures of the catalytic converter. An engine control receives a number of measurement data as input variables from measurement lines and derives control data for operation of the engine from the measurement data. Engine feed lines carry the control data to the engine. At least one data line delivers measured temperature values from the catalytic converter to the engine control as input variables in addition to other input variables.
摘要:
A device for reducing the number of particles in the exhaust gas of an internal combustion engine includes at least two structures through which an exhaust gas can flow, initially through a first structure and then through a second structure during operation. An electrical potential difference can be generated between the structures. In this way, the exhaust gas downstream of the second structure has fewer particles, averaged over time, than the exhaust gas upstream of the first structure. In addition, the particles downstream of the second structure have a larger mean diameter than those upstream of the first structure, so that it is possible to reduce emissions, in particular of fine dust, in the exhaust gas of internal combustion engines. A method for reducing the number of particles in the exhaust gas of an internal combustion engine, is also provided.
摘要:
A honeycomb body includes ceramic walls all being entirely formed of printed layers forming channels through which a fluid can flow. The channels lie next to one another. At least one of at least one measuring sensor or electrically conductive mass forms a monolithic, unitary structure with one of the ceramic walls. Sensor material may be used as an alternative to ceramic material. A method of producing the honeycomb body is also provided.
摘要:
A device for the treatment of an exhaust gas flow includes at least one inflow channel with a front region and a rear region and at least one return flow channel. A first coating is provided in the rear region of the at least one inflow channel. The coating assists an exothermal reaction of the exhaust gas flow. A device is formed in the front region of the inflow channel for the transfer of heat from a return flow channel. A method for operating a device for the treatment of an exhaust gas flow, a vehicle having the device and an operating method for an exhaust gas system of a vehicle having the device, are also provided.
摘要:
A device for treating exhaust gases includes a particle separator, an SCR catalytic converter for selectively reducing nitrogen oxides and an ammonia generator for generating ammonia as a selective reducing agent for reducing nitrogen oxides. The particle separator is provided in a main exhaust line and the ammonia generator is provided in a first secondary line. The first secondary line opens into the main exhaust line at a junction in such a way that an ammonia-containing gas stream generated in the ammonia generator can flow through the SCR catalytic converter. The method and the device advantageously permit the proportion of particles and nitrogen oxides (NOx) contained in the exhaust gas of an internal combustion engine to be reduced simultaneously, with the energy consumption for this reduction being small and at the same time the entire device being embodied as a compact unit.