摘要:
The device (1) has an adsorber (2) with a volume, V, through which an exhaust gas can flow. The volume can be calculated using an equation and the average values for the mass flow and temperature of the exhaust gas. The volume corresponds to the equation V = a + bt + c/m + dt 2> + e/(m 2>) + ft/m + gt 3> + h/(m 3>) + it/(m 2>) + kt 2>/m, where t is the average exhaust gas temperature, m is the average exhaust gas mass flow, a = 0.1660393, b = 0.0033635701, c = -1.7023186, d = 6.5277225 X 10 -> 6>, e = 195.657, f = -0.1373556, g = -9.0343024 X 10 -> 9>, h = -1273.9098, i = 1.0172767 and k = -1.442512 X 10 -> 5>.
摘要:
A metal honeycomb body having an axial length (L) and consisting of sheet metal layers (1; 10, 11) which are structured such that a fluid, especially the exhaust gas of an internal combustion engine, can flow through the honeycomb body in a direction of flow (S) from one incoming flow front face (12) to an outgoing flow front face (13). The sheet metal layers (1; 10, 11) are provided with a plurality openings (6), at least in partial areas thereof. The honeycomb body has holes (6) in all of the sheet metal layers (1; 10, 11) in a partial volume (T) of at least 55 % of the axial length (L) thereof and at a radial dimension of 20 mm.The holes (6) have respectively a surface of 1 -120 mm2; the surface of the sheet metal layers in the partial volume (T) is reduced by the holes (6) by 10-80 %, preferably 35-50 % in relation to a sheet metal layer without any holes; the distance (R2,R3) of the partial volume (T) to the front faces (12, 13) of the honeycomb is such that no holes come into contact with or overlap with the front-face edges of the sheet metal layers.
摘要:
The invention relates to a honeycomb body (1) comprising gas-permeable channels (2). The inner cross-section and number of said channels define a specific geometric surface area (GSA) of the honeycomb body, and they are at least partially separated from one another by separating walls (3). The material and thickness of said walls define a specific heat capacity with regard to the geometric unit area. The honeycomb body comprises an adsorption material provided especially for the adsorption of hydrocarbons. The specific geometric surface area (GSA) of the honeycomb body (1) is greater or equal to 37.5 m K/J [meter Kelvin/joule], preferably greater or equal to 40, especially greater than 60, said geometric surface area being divided by the specific heat capacity (cp) with regard to the area, measured at room temperature without adsorption material and eventual other coatings. The honeycomb body (1) can additionally comprise a catalytically active coating which works in an at least oxidative manner. The honeycomb body is preferably constructed of sheet metal layers having a thickness of less than or equal to 40 νm with more than 450 cpsi, especially more than 540 cpsi. This dimensioning of a hydrocarbon trap can be used for the purification of motor vehicle exhaust gases in order to reduce the emission of pollutants during the cold-start phase.
摘要:
The invention relates to a honeycomb body (1), at least having a housing (2) and a honeycomb structure (3) with a plurality of channels (4), wherein the honeycomb structure (3) is formed by at least one at least partially structured metal layer (5), which forms connecting points (6) that fix the honeycomb structure (3) in place, and wherein a cross-section (8) of the honeycomb structure (3) has radial zones (9, 10, 11) with connecting points (6), wherein in at least one zone (9, 10, 11) furthermore at least 1%, and no more than 20%, of the inner contact points (7) of the at least one at least partially structured metal layer (5) in the cross-section (8) form a connecting point (6), and the connecting points (6) have lengths (13) in the direction of a structure (12), wherein the lengths (13) of the connecting points (6) are different in at least two radial zones (9, 10, 11).
摘要:
The invention relates to a honeycombed body (1) comprising at least one housing (2) and a honeycombed structure (3) having a plurality of channels (4). Said honeycombed structure (3) is made of at least one at least partially structured metallic layer (5) that forms connecting points (6) fixing the honeycombed structure (3). At the most 20 % of the inner contact points (7) in a cross-section (8) of the honeycombed structure (3) form a connection point (6), and the connection points (6) are at a distance from each other such that a connection-free area (9), that is respectively the same size, is formed surrounding said points.
摘要:
The method according to the invention for evaporating a predeterminable volume of a fluid comprises the following steps: a) successive addition of at least one first partial volume at a first volume adding rate (17) and at least one predeterminable second partial volume that is different from the first partial volume, at a second volume adding rate (17) to a supply line (3); b) at least partial evaporating of the partial volumes such that a vapor film is formed between the partial volumes and a wall of the supply line (3); c) conveying the partial volumes through the supply line (3) to an evaporator surface (5); and d) applying the partial volumes to a region of the evaporator surface (5), the position of which is varied as a function of at least one of the following parameters: i) the mass of the corresponding partial volume and ii) the volume adding rate (17) of the corresponding partial volume. The method according to the invention and the device (1) according to the invention advantageously permit an evaporation of a fluid, particularly of a urea/water solution, in a manner that is as effective as possible. The utilization of the highest possible proportion of evaporator surfaces is achieved by the mass and/or volume addition rate-dependent distribution of the impingement surfaces on the evaporator surface (5). For this purpose, a heating strategy is advantageously employed in the region of the supply line (3) that ensures that the Leidenfrost effect occurs when the individual partial volumes are added. In this manner, a distribution that is as even as possible can be achieved using a corresponding configuration of the geometry of the evaporator channel (4).
摘要:
The invention relates to a method for providing a reducing agent-containing gas flow (24) in the exhaust gas system of an internal combustion engine. Said method comprises the following steps: A) providing at least one reducing agent precursor (12, 28, 34); B) evaporating the at least one reducing agent precursor (12, 28, 34) to give a gas flow (13); C) at least partially heating the gas flow (13) to temperatures of at least 250°C; D) at least partially converting the reducing agent precursor (12, 28, 34) in the gas flow (13) to a reducing agent; and E) adding the reducing agent-containing gas flow (24) to the exhaust gas (25) of the internal combustion engine. The method and the device according to the invention allow the provision of a reducing agent-containing gas flow (13) the quantity of which can be easily controlled and can be adapted to the dynamic changes in situation which occur especially in the exhaust gas system of mobile applications such as for example motorcars. According to the invention, the temperature of the first zone (7) is kept at 150°C or just below while the temperature of the second zone (8) is kept at more than 300°C. The hydrolytic catalyst (22) is hardly cooled when the reducing agent precursor is fed to the hydrolytic catalyst (22) in the form of steam, thereby having a positive effect on the process.
摘要:
The invention relates to an exhaust gas treating device comprising a particle separator (101), an SCR catalyst (102) for selectively reducing nitrogen oxides and an ammonia generator (103) for producing the ammonia in the form of a selective reduction agent for reducing said nitrogen oxides, wherein the particle separator (101) is placed in a main exhaust gas line (104), the ammonia generator (103) is mounted in a first auxiliary line (105) leading to the main exhaust gas line (104) opening, which is embodied in such a way that a gas flow containing the ammonia produced in the ammonia generator (103) is enable to pass through the SCR catalyst (102). The inventive method and device make it possible to simultaneously reduce the content in particles and nitrogen oxides (NOx) of the exhaust gases of an internal combustion engine (100), wherein the power consumption for said reduction is limited and the device can be entirely produced in the form of a compact unit.