DE2747959A1 - Internal combustion engine exhaust system and silencer - uses tubes with multiple bores to cool exhaust gas - Google Patents

Abstract

A silencer forming part of the exhaust system of an internal combustion engine consists of two concentric tubes (51, 52). These tubes are joined by radial walls (55) which extend longitudinally so that the annular space between the tubes is divided into a number of separate compartments (5). A cooling fluid flows in these compartments (5) in the opposite direction to the flow of gas in the central bore (50). The outer wall of the outer tube (52) has a number of radial fins (56) which also extend longitudinally. These fins help to dissipate the heat which has been transferred to the cooling medium by convection and radiation.

Description

Designation: "Thermal exhaust gas routing addendum 9" Description In the Application P 27 3C 007.8 describes an exhaust system for internal combustion engines has been, in which a steel sheet-limited inlet zone of the exhaust gas passes over is subordinated in an aluminum-limited subsequent room, whose peculiarity consists in the fact that its walls partly consist of elongated gas ducts exist in which a different amount of gas flows than that in the same moment passes the next room and partly radiates directly into the open atmosphere. in the In the first case, this creates a double wall, the thermal gradient of which is in the gas flow of the partial flow guides is directed, in the second case there is one simple wall with thermal gradient nacii a en. In Figures 1 and 2 of this In addition, the corresponding Figures 1 and 2 of S 27 50 007.3 are repeated, in which this is also shown as a schematic drawing. From the sheet steel limited Inlet chamber 1/2/20/21, the exhaust gas enters the aluminum border through the perforations 7 Subsequent room 8 (figure), the wall structure of which can be seen in FIG. 2: the Gas guide channels 12, delimited by the two walls 11 and 13, change into entire circumference with wall parts of a simple type which, apart from a little accumulation of material, consist only of the outer wall 11. The reason for this additional registration exists in that the claims of P 27 30 007.8 only that part of what is described there Defined technical facts, which mattered, by internal Apply a sheet steel wall 4 (Figure 1) to the shape of the aluminum wall described to form a second channel group 14 (claim 1 there). Furthermore is to be observed in the case of Figures 1 and 2 in the additional application submitted herewith, that the designated in Figure 1 with numeral 8 first subsequent space il; this mental Context is identical to the interior of Figure 2, there with the number 9 is designated.

It already emerges from the description of P 27 30 007.8 that the organization of the exhaust gas passage through the aluminum body in each case of depends on the construction of the two closing bodies in which the aluminum part is suspended is, so the closing body with the spaces 2 (20/21) and 15 and the closing body with the space formations 8 and 18. For this reason, the definition of the claims here only based on the fact that, according to Figure 2, the interior 9 of the hollow chamber annulus only partially from the hollow chambers 12, i.e. double-walled in relation to the free atmosphere, is surrounded and the other part with a simple wall (11). The merits of this Construction can be seen from Figure 3, in which the Hohikammerringraum with was provided with an oval profile to enable an extremely flat design. With this construction it is now completely indifferent, -.rie the closing body organize the gas flow; since the end of the gas guide spaces (9, 12 or 14) at least partly an aluminum wall radiating into the open atmosphere and every at least partial part of the outer wall ii seams is always the characteristic the main application P 27 19 513.7 met that the sheet steel limited inlet part of the exhaust gas connected first aluminum follow-up chamber at least partially into the is able to radiate free atmosphere directly with its wall. This feature was with the gas course within the figure 1 already with P 27 30 007.8 also for the Case presented that not the partial flow channels of the outer hollow chamber jacket (12) represent the first aluminum subsequent room, but this is the interior that is in 1 with 8 and in FIG. 2 of this application, with 9.

L e r s e i t e

Claims (2)

Pat entansprtiche 1. Exhaust system for internal combustion engines with a Hollow-chamber annulus made of aluminum, primarily as an extruded part that is open on both sides produced and hung on both sides in closing bodies, which the exhaust gas flow in such a way arrange that a usually staiilblechbegrenzten inlet space or such with another material higher heat resistance than aluminum the inlet in an aluminum-limited subsequent space follows according to P 27 30 007.3 (Figure 1 tree 8), characterized in that that of a hollow chamber jacket with rib-like subdivided partial flow channels (3 in Figure 1, 9 in the. Figures 2 and 3) at least partially with its wall (11) directly into the free atmosphere radiates. 2. Device according to the previous claim, characterized in that each of the elongated gas guide spaces, regardless of whether as an interior Hollow chamber jacket space or as its rib-subdivided partial flow channels within of the double-walled or multi-walled one at least partially surrounding the interior Sheath body (Figure 3) partially radiating directly into the open atmosphere have simple wall (11),