CN-121993310-A - Method and device for operating an internal combustion engine with hydrogen

Abstract

A method and a device for operating an internal combustion engine (10) with hydrogen are proposed, wherein hydrogen is blown directly into a combustion chamber (5) of the internal combustion engine. In this case, after the air inlet valve (6) of the internal combustion engine has been closed, hydrogen is blown in an angle range that is later than 40 DEG crank angle.

Inventors

• H. KOS
• M. Lippish
• O. Turk
• T. Burch e

Assignees

• 罗伯特·博世有限公司

Dates

Publication Date

20260508

Application Date

20251103

Priority Date

20241104

Claims (8)

1. 1. Method for operating an internal combustion engine (10) with hydrogen, which is blown directly into a combustion chamber (5) of the internal combustion engine, characterized in that the hydrogen is blown in an angular range later than 40 ° crank angle after the air inlet valve (6) of the internal combustion engine is closed.
2. 2. The method according to claim 1, characterized in that the angular range for the blowing-in is selected as late as possible.
3. 3. Method according to claim 2, characterized in that for the selection of the angular range, the pressure in the combustion chamber (5) due to compression after the closing of the air inlet valve (6) is taken into account.
4. 4. A method according to claim 2 or 3, characterized in that for the selection of the angular range, the amount of hydrogen blown in is taken into account.
5. 5. The method according to claims 2 to 4, characterized in that for the selection of the angular range, the centre of gravity of the combustion of the hydrogen is taken into account.
6. 6. The method of claim 5, wherein the center of gravity of the combustion is affected by selecting an ignition angle of the combustion.
7. 7. A method according to any one of the preceding claims, characterized in that the knocking tendency of the combustion is taken into account for the selection of the angular range.
8. 8. Device for operating an internal combustion engine (10) with hydrogen, which is blown directly into a combustion chamber (5) of the internal combustion engine (10), characterized in that the device causes the hydrogen to be blown in an angular range later than 40 ° crank angle after the air inlet valve (6) of the internal combustion engine is closed.

Description

Method and device for operating an internal combustion engine with hydrogen Technical Field The present invention relates to a method and apparatus for operating an internal combustion engine with hydrogen. Background Methods and devices for operating an internal combustion engine with hydrogen are known, in which hydrogen is blown directly into the combustion chamber of the internal combustion engine. A corresponding internal combustion engine and a valve for blowing hydrogen directly into a combustion chamber of the internal combustion engine are known from DE 10 2023 206 011. Disclosure of Invention THE ADVANTAGES OF THE PRESENT INVENTION In contrast, the method according to the invention and the device according to the invention, which have the features of the independent claims, have the advantage that an improved operation of the internal combustion engine can be achieved. In particular, knocking of combustion in the internal combustion engine is avoided, whereby more efficient operation of the internal combustion engine can be achieved. Further advantages and improvements result from the measures of the dependent claims. By selecting the angle range as late as possible for the injection, the operation of the internal combustion engine, in particular the knocking tendency of the internal combustion engine, is improved. By taking into account the pressure in the combustion chamber due to compression, the optimal angular range for injection is optimized. For this optimization, the amount of hydrogen blown in and the centre of gravity of the combustion are also taken into account in an advantageous manner. In particular, the center of gravity of the combustion can be influenced by selecting a suitable ignition angle. The knock tendency of the internal combustion engine is then optimized by the measures mentioned. Drawings Embodiments of the invention are illustrated in the accompanying drawings and explained in more detail in the following description. Wherein: FIG. 1 shows a schematic diagram of an internal combustion engine, and Fig. 2 shows a characteristic curve family of knocking tendency with respect to the angle of the blowing of hydrogen gas. Detailed Description Fig. 1 schematically shows an internal combustion engine 10 operated with hydrogen, which has a cylinder 3 in which a piston 4 is arranged. Above the piston 4, the cylinder 3 forms a combustion chamber 5 into which a mixture of hydrogen and air is introduced and combusted. The pressure in the combustion chamber 5 is increased by the combustion of the hydrogen-air mixture in the combustion chamber 5 and is converted into mechanical work by the movement of the piston 4 in the cylinder 3 by means of a connecting rod and a crankshaft, which are not shown here. Thus, generally known gasoline internal combustion engines are referred to herein. In order to supply air into the combustion chamber 5, an intake pipe 2 is provided in which the amount of supplied air is controlled by the throttle plate 1. The amount of air introduced into the combustion chamber 5 is controlled by opening and closing the throttle plate 1. Furthermore, a blowing valve 9 is provided, through which hydrogen is blown directly into the combustion chamber 5. Ignition of the mixture of hydrogen and air in the combustion chamber 5 is achieved by means of a spark plug not shown in the drawings. An exhaust pipe 8 is provided for the exhaust gas to be led away after combustion, through which the combusted exhaust gas is discharged from the combustion chamber 5. In addition, an air inlet valve 6 and an exhaust gas outlet valve 7 are also schematically shown in fig. 1. By opening and closing the air inlet valve 6 and the exhaust gas outlet valve 7, the combustion chamber 5 is connected with the intake pipe 2 or the exhaust pipe 8 according to the operating stage of the internal combustion engine 10. For controlling the internal combustion engine 10, a control device 11 is also shown, which generates signals for actuating the throttle plate 1 or the blow-in valve 9. Such an internal combustion engine 10 is typically operated in a 4-stroke method. In this case, fresh air is sucked into the combustion chamber 5 in a first suction stroke by opening the air inlet valve 6 and the piston 4 moving from top dead center to bottom dead center. A negative pressure is generated in the combustion chamber by the movement of the piston, and air is sucked in through the intake pipe 2 due to the negative pressure. By opening the throttle plate 1, the amount of air introduced into the combustion chamber 5 is controlled here. A compression stroke is then performed in which the piston 4 moves again from the bottom dead center to the top dead center and thus compresses the gas in the combustion chamber 5. In this compression stroke, too, hydrogen is injected directly into the combustion chamber 5 through the blow-in valve 9. The compression stroke is followed by a combustion stroke in which a mixture o