JPH11148360A - Reciprocating type internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To keep air charge to all cylinders uniform with a simple means. SOLUTION: This reciprocating type internal combustion engine, which involves at least one cylinders 1-9 arranged in line with each other and in which supercharging air is introduced into the respective cylinders through a supercharging air pipe 10 extending along the cylinders of one row, one end of the supercharging air pipe is connected to an exhaust turbine supercharger through a supercharging air cooler 12, and the other end is closed, a space 13 for increasing the volume of the supercharging air pipe 10 by an amount of auxiliary air volume is provided at the closed end of the supercharging air pipe 10, thus it is possible to keep air charge to all the cylinders 1-9 uniform.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises at least one row of cylinders arranged side by side, and supercharging air is introduced into each cylinder by a supercharging air pipe extending along the cylinder row. The present invention relates to a reciprocating internal combustion engine having one end connected to an exhaust turbine supercharger via a supercharged air cooler and the other end closed. The invention is particularly advantageously applied to large diesel or gas engines for ships or power plants.

[0002]

2. Description of the Related Art In an internal combustion engine of this type, a cylinder may be supplied with air unevenly at a predetermined number of cylinders, a predetermined number of revolutions, and a predetermined ignition sequence. Apart from the fact that optimal combustion is impaired by this, the individual cylinders are thermally overloaded. It has been found that the cause of this problem is that one or more natural frequencies of the air column in the supercharged air tube resonate with one or more harmonic frequencies of the periodic excitation by air intake of individual cylinders .

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a reciprocating internal combustion engine of the type described at the outset, in which the supply of air to all cylinders is made uniform by simple means.

[0004]

According to the present invention,
The problem is solved by providing a space at the closed end of the charging air line which increases the volume of the charging air line by the auxiliary air volume.

[0005]

By locating the auxiliary air volume there instead of closing the charging air line at the closed end, the natural frequency of the air column in the charging air line is reduced. Therefore, no resonance occurs at the rated speed. This measure is sufficient for an internal combustion engine operating at a constant speed.

[0006] Since the natural frequency is moved downward by the auxiliary air volume, the resonance occurrence point also moves toward a lower rotational speed. This is because, for a reciprocating internal combustion engine that is not operated at a constant rotation speed but operated on a propeller curve, for example, when the rotation speed is lower than the rated rotation speed, a non-uniform air supply accompanies each cylinder. It means that a large thermal load occurs. This is particularly disadvantageous since the air supply is inherently worse during partial load operation on the propeller curve than during full load operation.

This disadvantage is eliminated in an embodiment of the invention by the provision of a shut-off device, for example a butterfly valve, between the charging air line and the space forming the auxiliary air volume. When operating at the rated speed in such an internal combustion engine, the shut-off device is opened in order to reduce the natural frequency and prevent resonance, whereby the excitation frequency is placed above the natural frequency. When operating at a speed lower than the rated speed, the natural frequency is set to a value in the case where the auxiliary air volume does not exist, the shut-off device is closed to prevent resonance,
Then the excitation frequency is placed below the natural frequency.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 schematically shows the main components of an embodiment of the present invention.

The illustrated reciprocating internal combustion engine has nine cylinders 1-9 arranged in a row. However, the invention is also applicable to reciprocating internal combustion engines with different numbers of cylinders. A supercharged air pipe 10 extends along the cylinder row, and an inlet passage 11 having a small cross-sectional area branches off from the supercharged air pipe 10 toward each of the cylinders 1 to 9. Air is introduced from a not-shown exhaust turbine supercharger into the supercharged air pipe 10 through the supercharged air cooler 12 in the direction of arrow a.
At the normally closed other end of the supercharging air pipe 10, there is provided a space 13 forming an auxiliary air volume. In the case of this embodiment, a reciprocating internal combustion engine operated at a variable speed is targeted, so that a shutoff device 14 is provided between the supercharged air pipe 10 and the space 13. This shut-off device can be formed as a simple butterfly valve. The shut-off device 14 is advantageously controlled automatically in relation to the engine speed such that it opens at a rated speed and closes at a predetermined low speed. The cylinders 1 to 9 are connected to each exhaust passage 15
Are connected to a common exhaust pipe 16. If the reciprocating internal combustion engine is to be operated only at a constant speed, the shut-off device 14 is omitted.

[0010] If the reciprocating internal combustion engine is formed as a V-type engine with two supercharging air pipes, the second supercharging air pipe for the second row of cylinders also has a space defining an auxiliary air volume. .

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing main components of an embodiment of the present invention.

[Explanation of symbols]

 1-9 Cylinder 10 Supercharged air pipe 11 Inlet passage 12 Supercharged air cooler 13 Space 14 Shutoff device 15 Exhaust passage 16 Exhaust pipe

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Robert Glauber Germany 86316 Friedberg am Beerweg 21 (72) Inventor Thomas Lauell Germany 86391 Stadtbergen am Graben 26

Claims (3)

[Claims] 1. A supercharged air pipe is provided with at least one row of cylinders arranged side by side. Supercharged air is introduced into each cylinder by a supercharged air pipe extending along the cylinder row. In a reciprocating internal combustion engine which is connected to an exhaust turbine supercharger via a heater and has the other end closed, the volume of the supercharged air pipe (10) is added to the closed end of the supercharged air pipe (10). Space that increases by volume (1
(3) A reciprocating internal combustion engine, wherein (3) is provided. 2. The reciprocating type according to claim 1, wherein a shut-off device (14) such as a butterfly valve is arranged between the supercharging air pipe (10) and the space (13). Internal combustion engine. 3. The reciprocating internal combustion engine according to claim 2, wherein the shut-off device is operated as a function of the rotational speed of the internal combustion engine.