摘要:
A method for analyzing a condition of at least one partial volume of a catalytic converter through which a gas mixture flows, includes measuring a temperature with a sensor at least at one location or in a region within a partial volume during a change of chemical and/or physical properties of the gas mixture. The location or the region and a configuration of the sensor are selected in such a way that a reaction of the measured temperature to a change of the properties of the gas mixture is at least approximately representative of a reaction of the temperature in the partial volume of the catalytic converter. Set point values are determined for the respective change in the properties of the gas mixture on the basis of a thermodynamic model while taking physical boundary conditions and properties of the partial volume into account. The reaction of the measured temperature is determined and compared with the set point values.
摘要:
A honeycomb body, in particular a catalyst carrier body, includes at least partially structured sheet-metal layers forming a multiplicity of channels through which a fluid can flow. An electrically insulating intermediate layer has at least two sheet-metal layers being mechanically clamped together and an insulating layer electrically insulating the at least two sheet-metal layers from one another.
摘要:
A catalytic converter is connected downstream of an internal combustion engine of a motor vehicle and has at least a short portion to be quickly electrically heated. A method for controlling the heating of the catalytic converter includes turning on electric heating only after a delay after starting the internal combustion engine, if a rate of temperature change in the heatable portion of the catalytic converter, being caused by heat contained in exhaust gases of the internal combustion engine, is no greater than approximately a rate of temperature change attainable by electric heating.
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 assembly, in particular a catalyst carrier body, includes at least one electrically heatable honeycomb body having layered metal sheets forming a stack with a plurality of channels through which a fluid can flow. The metal sheets have a thickness of about 0.03 to 0.12 mm. The honeycomb body is electrically subdivided with regard to its cross-section or in its axial direction. At least one electric current path is formed through the metal sheets with an electric resistance of between 0.01 and 2 .OMEGA.. The resistance, which is dependent on the temperature, can be used for monitoring and regulating the honeycomb assembly.
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:
A honeycomb body assembly, in particular a catalyst carrier body, comprises at least one electrically heatable honeycomb body having layered metal sheets forming a stack with a plurality of channels through which a fluid can flow. The metal sheets have a thickness of about 0.03 to 0.12 mm. The honeycomb body is electrically subdivided with regard to its cross-section and/or in its axial direction. At least one electric current path is formed through the metal sheets with an electric resistance of between 0.01 and 2 .OMEGA.. The resistance, which is dependent on the temperature, can be used for monitoring and regulating the honeycomb assembly.
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 catalyzer configuration, in particular for internal combustion engines, has a diffusor which widens in the direction of flow disposed upstream of a honeycomb body, a converger which narrows in the direction of flow downstream of the catalyst body, and at least one flow guiding body located within the diffusor and/or converger. In order to achieve a uniform inflow at the front side of the catalyst body without excessively throttling the exhaust gas flow, a flow guide body composed of a multiplicity of adjacent and/or imbricated channels having at least partially an increasing cross-section in the direction of flow is disposed in the diffusor. The individual channels preferably have an opening angle .alpha. that prevents burbling at the walls of the individual channels. In addition, the flow guide body can be coated with a catalytically active material, thus allowing the volume of the diffusor and/or of the converger to be used for housing catalytically active surfaces.