DD207953A1 - COMBUSTION INSERTION FOR INTERNAL COMBUSTION ENGINE WITH FUEL INJECTION INTO A SIDE BURNER - Google Patents

Abstract

THE INVENTION INCLUDING A COMBUSTION CHAMBER OF APPLICATION, THROUGH SPECIAL DESIGN of the overflow, THE MAIN AND SUB COMBUSTION JOINED, IN CONJUNCTION M. OTHER SIZE, LOCATION U. FORM DETERMINED FACTORS I. WHOLE LOAD RANGE OF BURNING ENGINES REDUCTION OF FUEL CONSUMPTION, SMOKE TRUE EXERCISE, SOUND LEVEL U. EGT EFFECT , D. INTERCHANGEABILITY & SUSTAINABILITY OF COMBUSTIBLE CONVENTIONAL CONSTRUCTION TYPE IS NOT CONSIDERED THAT I AUTHORIZE THAT ITSELF WITH EASY MEANS AND LOW COST COMBUSTION OF COMBUSTION BATTERIES, OF WHICH OVERHEAD CHANNELS ARE CONSTANT CROSS SECTION, CAN BE REINFORCED.

Description

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Inventor: Klaus Winkler Berlin, the 18 · 9 _β 198ΐ

Horst Nicolai Klaus Rohloff

Attorney-at-law: Patent-Ing. Ullrich ^ cheffler

Title of the invention

Combustion insert for internal combustion engine with fuel injection into a secondary combustion chamber

Field of application of the invention

The invention relates to a combustion chamber insert, for an arranged in the cylinder head auxiliary combustion chamber, primarily for pre-chambers of internal combustion engines with fuel injection. The combustion chamber insert connects the main combustion chamber with the secondary combustion chamber by way of overflow ducts arranged in the region of the burner floor.

The fuel injection takes place in the secondary combustion chamber. The combustion chamber insert is fixed non-positively in or on the secondary combustion chamber. .

Characteristics of the known technical solutions It is known that the achievement of good mixture formation in internal combustion engines with fuel injection in secondary combustion chambers in addition to the design of the combustion chambers depends essentially on the execution of the combustion chamber inserts. In order to achieve economic parameters for the internal combustion engine, the most varied designs of combustion chamber inserts are known. -

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As a conventional embodiment, the aaer to the 'Neben-' combustion chamber, screwed combustion chamber insert with diffuser-like side combustion chamber side extension, central neck bore with main combustion chamber side adjacent to the piston crown inclined overflow wells is known. It will find Brennkamme reinsät ze with radially or tangentially arranged, more or less inclined to the piston crown overflow channels of different cross-sectional shape application. In addition, there are combustion chamber inserts with inner baffles and Leitkörpern to improve mixture formation and flow.

As a result of the high thermal load, the firing chambers are manufactured from heat- and scale-resistant, heat-resistant materials.

Number, location, cross-sectional size and shape of the overflow are next to the decisive factors for the combustion process and mixture formation factors, such as throttling and Überi ebeverluste, among other things, determined by the remaining between the overflow holes webs. The size of the webs significantly determines the life of this component.

Published descriptions show a two-part

t welding connected antechamber insert. The neck bore is in the main combustion chamber side part, expediently nozzle-shaped, expanded to a larger diameter in the form of a full or partial sphere, from which the overflow channels in a cylindrical, outwardly widening or nozzle-shaped constricting shape substantially radiate. The insert bottom is designed essentially hemispherical. To the outwardly widening execution of the overflow channels are no further details, only in the explanation of the illustrations is referenced nozzle-shaped outwardly extended Überströmknälen '.

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Another publication describes to achieve a directed flow a Vorkammereinsatz, which is provided with a central guide body. In the resulting annular gap, the upper flow channels open approximately horizontally. / ' The overflow are arranged approximately tangentially and expanded diffuser-like.

A third publication describes a Vorkammereinsatz, which is provided, inter alia, to improve the cooling, especially the Vorkammereinsζζ it, with a reinforced wall in the overflow channels. By increasing the wall thickness and the associated lengthening of the overflow channel length, in order to avoid the inevitably caused increase in losses, an expanding, funnel-shaped countersink was executed. This countersink has the goal of leaving the relevant length of the transfer channels unchanged. The overflow channels open into a main combustion chamber side, beveled, designed as a curved lateral surface, wall surface.

In a fourth publication, the overflow channels are designed as elongated holes aligned along the cylinder axis in the case of a burner attachment for prechamber arranged centrally in the cylinder head. The ratio of the area of the neck bore to the area of the overflow channels is not greater than 1sO, 85. The wall of the burner attachment is weakened by no more than 4 to 0 percent through the transfer channels. The overflow channels are inclined towards the piston crown and penetrate the wall radially or, starting from the neck bore, tangentially or in any intermediate position between radial and tangential.

Object of the invention

The aim of the invention, while maintaining conventional technologies, without significantly increasing the degree of difficulty and without the use of additional or built-in parts

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an improvement of the combustion and mixture formation process in internal combustion engines with fuel injection in secondary combustion chambers, primarily with Brennkamme reinsätze conventional design to achieve. In this case, cost-effectiveness and environmental friendliness are determining parameters by optimizing geometric sizes and conditions at the combustion chamber, especially in the area of overflow channels: and to improve the transition to Nebenbrennraunij.

The aim is, moreover, to carry out the geometric changes such that at any time with little effort combustor inserts, the conventional design, according to the invention, can be redesigned. -

The object of the invention is to design a combustion chamber insert in such a way that the unavoidable flow, throttle and overshoot losses occur. be reduced from the main to the secondary combustion chamber and vice versa to achieve optimum parameters. λ According to the invention by arranging a main combustion chamber side adjacent to the cylindrical part conical extension of Überströmquerschnittes the onflow of channels constant cross-section with sharp edges inevitably resulting edgebanding with ßtrahlkontraktion significantly reduced and simultane- ously achieved leadership in the inflow into the secondary combustion chamber. In the reverse flow pattern, ie from the secondary combustion chamber to the main combustion chamber, vortex formation, which occurs as a loss in the case of discontinuous cross-sectional enlargements, is also achieved due to the constant cross-section of sharp-edged channels.

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In the vortex field forming during the outflow, therefore, only the medium located in the conical enlargement, which volume is substantially limited in terms of the volume of the free jet, is swirled by the conical surface after detachment, so that the exit loss is reduced. Simultaneously, a flow of the acceleration ^v flowing at supersonic velocity medium is achieved by the extension and thus the mixing process in the main combustion chamber favored by be altered by the resulting increase in the exit velocity and momentum core length and penetration depth of the beam. The induced by pulse exchange beam resolution causes the mixing with the main combustion chamber side existing medium.

To achieve optimal mixture formation and combustion, the arranged conical extension of the preferably circular running overflow channel is inventively designed as an obliquely cut circular truncated cone whose small boundary surface is perpendicular to the center line of the overflow and the large boundary surface main combustion chamber side with evenly curved lateral surface predominantly runs parallel to the combustion chamber insert axis and thereby with a minor proportion in a compound designed as a radius or chamfer ^; can leak from cylinder jacket and burner bottom. The conical enlargement of the overflow channels is intended to be formed with a double cone angle alpha = 20... 50 ° and a truncated cone length ^M t "relative to overflow channel length" 1 "of t = (0.3... 0.5) 'x 1.

The, mainly radially to the combustion chamber insert axis: arranged, evenly distributed around the circumference, preferably circular Überströmkanale with conical extensions, which can also be right or left tangential to the neck bore or in an intermediate position 'can be at an angle to the combustion chamber insert axis beta = 65 ·· 75 ° inclined towards the piston crown.

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The ratio of the 'Querschnittses'der' neck bore with the diameter D to the sum of the smallest cross sections of the overflow e e should = 0.95.

For the mixture formation and ignition conditions to be created in the secondary combustion chamber, the Bremkamraersatz is known per se with. a diffuser-like extension and one in the secondary.

., Brennraum projecting annular vortex edge provided. The vertebral edge height h is designed with h zt 0.5 χ D. The area between the overflow channels represents a critical heat-conducting cross-section. To achieve a long service life, the individual bars should = 8 percent and the total area of weakening =? 50 percent of the unbroken ring cross section amount. Thus, a sufficient security against tearing or tearing of the burner bottom due to Tem-. achieved. . '

Also advantageous for life and mixture formation is the formation of the transition from Halsbohrung- to the burner bottom in the form of a radius of size R = (0.2 ... 0.5) χ D. The secondary combustion chamber with the combustion chambers insatζ can center, off-center, vertical or slightly inclined to be arranged to the cylinder axis of the internal combustion engine. The use of the combustion chamber inserts according to the invention causes a reduction in the specific fuel consumption in the entire load range of self-priming and supercharged internal combustion engines, both generator and propeller operation. Furthermore, the combustion chamber-forming and exhaust gas-carrying components ^x and assemblies are thermally relieved by an average reduction of the exhaust gas temperature by about 20'Kelvin. The improvement of the uiriweltbelastenden parameters flue gas turbidity and noise level is another advantage. For the frequency-dependent sound pressure level, a reduction of the level values by 1 ... 2 decibels.

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On. Another advantage of this design is that with simple means any time Brennerkammereinsätze can be transformed with Überströflikanälen constant cross-section. A deterioration of the interchangeability is not given because in multi-cylinder internal combustion Engines - limited construction - partially conventional, partially inventive design - no harmful effects. · Result.

embodiment

The combustion chamber insert according to the invention will be explained in the following embodiment.

FIG. 1 shows a longitudinal section through the combustion chamber insert and the auxiliary combustion chamber, partially shown

Figure 2 shows the section A-A through the Brennkainmereinsats in the region of the critical Wärmeleitquerschnittes. ;

The combustion chamber insert 1 is connected to the auxiliary combustion chamber 16 and is arranged replaceably in the cylinder head. The connection of main and Nebenbrennrsum is t given by overflow 2, the main combustion chamber side a conical enlargement 3 - characterized by the double cone angle 7 and the truncated cone 9 - have. Starting from the shark bore 11, the Bronnkamniere is radially penetrated in set wall of the over- 'strömkanälen, wherein also, not shown in the figures, left or right tangential course to the neck hole or an intermediate position between tangential and radial is possible. The remaining "webs 14 thus have different shape depending on Überströmkanalanordnung.

The overflow channels 2 with the conical enlargement 3 are inclined at an inclination angle 8 to the incinerator insert axis. '

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The small Begrenzungsflächü 4 of the conical extension 3 is perpendicular to the overflow channel center line and the large boundary surface 5 extends as a uniformly curved cylinder jacket 17 parallel to the combustion chamber insert axis 6. The connections of the cylinder jacket 1? and the neck bore 11 at the burner bottom I5 are preferably designed as radii. The overflow channel length 10 is formed by both the preferably circular-cylindrical and the conical portion. Nebenbrennräuraseitig the neck hole 11 opens into the diffuser-like extension 12, which ends with the protruding into the secondary combustion space vortex edge I3. ".. '- ..

Claims (3)

⁹ 233837 2 Erfindungsarispruch 1. Brennkamraereinsatz for internal combustion engine with fuel injection into a secondary combustion chamber and Überströmkanälen, characterized in that to achieve low-loss ßtrömungsvorgänge the transfer channels (2) are provided in preferred circular cross-section main combustion chamber side with a conical extension (3) in the form of an obliquely truncated circular truncated cone, wherein the small Boundary surface (4) is perpendicular to the Überströmkanalmittellinie and its large boundary surface (5) or a majority of this evenly curved cylinder jacket (17) parallel to the Brennerkammereinsatzachse (6) and a · possible minor portion of the large boundary surface (5) in a than Radius or chamfered compound of cylinder jacket (17) and burner bottom (15) can run out, the truncated cone length (9) between 30 to 50 percent of Überströmkanallänge (10), the double bevel angle between 20 and 50 degrees and whose angle of inclination to the combustor insert axis (8) is between 65 and 75 degrees. 2. combustion chamber insert according to item 1, characterized in that between the overflow channels with conical extension (2, 3) »di © remaining webs (14) provide sufficiently large cross sections for the heat conduction, wherein the individual web cross section greater than 8 percent and the cross-sectional weakening in total less than 50 percent of the neck bore (11) and cylinder jacket (17) limited impenetrable annular cross-section is. 3. combustion chamber insert according to item 1, characterized in that the ratio cross section of the neck bore (11) to the sum of the narrowest cross sections of the overflow (2) is greater than 0.95. -JSr - 233837 2 Combustion chamber insert according to item 1, g e k e η η ζ eich net in that-the overflow channels (2, 3) penetrate the combustion chamber insert wall radially or tangentially to the neck bore (11) or in any arbitrary intermediate position of radial and tangential arrangement. For this 1 string drawings