Combustion engine

Abstract

A combustion engine for combustion of an air-fuel mixture containing air and fuel, comprising at least one temperature adjusting means for cooling or heating the air, fuel, and/or air-fuel mixture and a control unit configured to determine the methane number and/or hydrogen content of the fuel and/or air-fuel mixture, wherein the control unit is configured to control a temperature of the air, fuel and/or air-fuel mixture based on the determined methane number and/or hydrogen content by controlling the at least one temperature adjusting means.

Claims

1. A combustion engine for combustion of an air-fuel mixture containing air and fuel, comprising: at least one temperature adjuster configured to cool or heat the air, the fuel, and/or the air-fuel mixture; and a controller configured to obtain a temperature of the air-fuel mixture downstream from mixing of the air and the fuel and upstream from the at least one temperature adjuster, and control the temperature of the air-fuel mixture based on a target knock value versus an actual knock value by controlling the at least one temperature adjuster downstream from compression of the air-fuel mixture and upstream from a combustion chamber of the combustion engine, wherein the target knock value and the actual knock value comprise a knock resistance or a knock probability.

2. The combustion engine of claim 1, comprising: a mixer configured to mix the air the fuel to obtain the air-fuel mixture; a sensor configured to sense the temperature of the air-fuel mixture; a compressor configured to compress the air-fuel mixture downstream from the sensor; and the at least one temperature adjuster downstream from the compressor, wherein the at least one temperature adjuster comprises at least one intercooler and/or at least one fluid circuit with a temperature adjusting fluid.

3. The combustion engine of claim 1, wherein the controller is configured to shift the actual knock value towards the target knock value via control of the temperature of the fuel and/or the air-fuel mixture by controlling the at least one temperature adjuster.

4. The combustion engine of claim 1, wherein the controller is configured to control the temperature of the fuel and/or the air-fuel mixture so that the combustion engine operates at a constant and/or a full load and/or a rotational speed with the target knock value within a range of 0 to 1.

5. The combustion engine of claim 1, wherein the fuel contains hydrogen and the actual knock value is based at least partially on a hydrogen content of the hydrogen in the fuel and/or the air-fuel mixture.

6. The combustion engine of claim 1, further comprising at least one sensor configured to sense: a methane number of the fuel and/or air-fuel mixture; and/or a hydrogen content of the fuel and/or air-fuel mixture; and/or physical parameters comprising the temperature and/or a humidity of the air, the fuel and/or the air-fuel mixture; and/or chemical parameters of the air, the fuel and/or the air-fuel mixture; and/or a composition of the air, the fuel and/or the air-fuel mixture; and/or a content of an exhaust gas in the air or charge air; and/or knock; and generates data thereof, wherein the controller is configured to process the data generated by the at least one sensor to derive at least one quality parameter of the air, the fuel and/or the air-fuel mixture.

7. The combustion engine of claim 1, wherein the controller is configured to control the temperature of the fuel and/or the air-fuel mixture at least partially based on a hydrogen content of the fuel and/or the air-fuel mixture by controlling the at least one temperature adjuster.

8. The combustion engine of claim 1, wherein the controller is configured to control the temperature of the fuel and/or the air-fuel mixture at least partially based on a methane number of the fuel and/or the air-fuel mixture by controlling the at least one temperature adjuster.

9. The combustion engine of claim 1, wherein the combustion engine is a reciprocating engine.

10. The combustion engine of claim 1, comprising a turbocharger comprising a turbine coupled to a compressor, and the at least one temperature adjuster comprises an intercooler disposed between the compressor and a combustion chamber of the combustion engine.

11. The combustion engine of claim 10, comprising at least one sensor coupled to the controller, wherein the at least one sensor is disposed upstream from the compressor.

12. The combustion engine of claim 1, wherein the at least one temperature adjuster comprises a plurality of intercoolers arranged in a plurality of stages, and the controller is configured to control the temperature of the fuel and/or the air-fuel mixture at one of the plurality of stages having a lowest temperature and/or a last stage of the plurality of stages.

13. The combustion engine of claim 1, wherein the controller is configured to selectively increase and decrease the temperature of the fuel and/or the air-fuel mixture in real-time to operate in a knock-free regime or the target knock value in response to variations in fuel quality determined at least by a methane number and/or a hydrogen content.

14. A method for operation of a combustion engine for combustion of an air-fuel mixture containing air and fuel, wherein the method comprises: determining a target knock value and an actual knock value of the fuel and/or the air-fuel mixture; obtaining a temperature of the air-fuel mixture downstream from mixing of the air and the fuel and upstream from at least one temperature adjuster; and controlling the temperature of the air-fuel mixture based on the target knock value versus the actual knock value by controlling the at least one temperature adjuster downstream from compression of the air-fuel mixture and upstream from a combustion chamber of the combustion engine, wherein the target knock value and the actual knock value comprise a knock resistance or a knock probability.

15. The method of claim 14, further comprising: determining the actual knock value of the fuel and/or the air-fuel mixture based on the fuel and/or a methane number and/or a hydrogen content; and calculating the target knock value of the fuel and/or the air-fuel mixture; and determining a target temperature and/or a target temperature difference of the fuel and/or the air-fuel mixture so that the actual knock value equals the target knock value; and controlling the temperature of the fuel and/or the air-fuel mixture by conditioning the fuel and/or the air-fuel mixture to reach the target temperature and/or the target temperature difference using the at least one temperature adjuster.

16. A computer program product for operation of a combustion engine for combustion of an air-fuel mixture containing air and fuel, comprising instructions causing an executing computer to perform the following: determining a target knock value and an actual knock value of the fuel and/or the air-fuel mixture; obtaining a temperature of the air-fuel mixture downstream from mixing of the air and the fuel and upstream from at least one temperature adjuster; and outputting control signals to at least one temperature adjuster to control the temperature of the air-fuel mixture based on the target knock value versus the actual knock value downstream from compression of the air-fuel mixture and upstream from a combustion chamber of the combustion engine, wherein the target knock value and the actual knock value comprise a knock resistance or a knock probability.

17. The computer program product of claim 16, wherein the instructions causing an executing computer to furthermore perform the following: computing and/or using a methane number and/or a hydrogen content of the fuel and/or the air-fuel mixture and/or the combustion engine, and determining the actual knock value based on the fuel and/or the methane number and/or the hydrogen content, and setting the target knock value for the combustion engine, and checking whether the target knock value equals the actual knock value, and if the actual knock value differs from the target knock value, deriving a target temperature and/or temperature difference of the fuel and/or the air-fuel mixture to shift the actual knock value to the target knock value.

18. The method of claim 14, wherein controlling the temperature comprises selectively increasing and decreasing the temperature of the fuel and/or the air-fuel mixture in real-time to operate in a knock-free regime or the target knock value in response to variations in fuel quality determined at least by a methane number and/or a hydrogen content.

19. The computer program product of claim 16, wherein outputting the control signals to control the temperature comprises selectively increasing and decreasing the temperature of the fuel and/or the air-fuel mixture in real-time to operate in a knock-free regime or the target knock value in response to variations in fuel quality determined at least by a methane number and/or a hydrogen content.

20. A combustion engine for combustion of an air-fuel mixture containing air and fuel, comprising: a mixer configured to mix the air the fuel to obtain the air-fuel mixture; a sensor configured to sense the temperature of the air-fuel mixture; a compressor configured to compress the air-fuel mixture downstream from the sensor; at least one temperature adjuster configured to cool or heat the air, the fuel, and/or the air-fuel mixture, wherein the at least one temperature adjuster is downstream from the compressor, wherein the at least one temperature adjuster comprises at least one intercooler and/or at least one fluid circuit with a temperature adjusting fluid; and a controller configured to control a temperature of the fuel and/or the air-fuel mixture based on a target knock value versus an actual knock value by controlling the at least one temperature adjuster, wherein the target knock value and the actual knock value comprise a knock resistance or a knock probability.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further details and advantages of the present invention will be described by means of the figures and their specific description hereinafter, wherein:

(2) FIG. 1 shows a schematic of an embodiment of a combustion engine proposed,

(3) FIGS. 2 and 3 show a first variant of a temperature control mechanism for a combustion engine proposed, and

(4) FIGS. 4 and 5 show a second variant of a temperature control mechanism for a combustion engine proposed.

DETAILED DESCRIPTION

(5) FIG. 1 shows an embodiment of a combustion engine 1 for combustion of an air-fuel mixture 2 containing air 3 and fuel 4, comprising at least one temperature adjusting means 5 (e.g., temperature adjuster) for cooling or heating the air 3 and/or fuel 4 and/or air-fuel mixture 2 and a control unit 6 (e.g., controller) configured to determine the methane number 7 and/or hydrogen content 8 of the fuel 4 and/or air-fuel mixture 2, wherein the control unit 6 is configured to control a temperature of the air 3 and/or fuel 4 and/or air-fuel mixture 2 based on the determined methane number 7 and/or hydrogen content 8 by controlling the at least one temperature adjusting means 5.

(6) This embodiment of a combustion engine 1 comprises an air-fuel mixing means 15 (e.g., air-fuel mixer), which mixes the air 3 and fuel 4 to an air-fuel mixture 2.

(7) This embodiment comprises at least one sensor 12, which can at least measure the methane number 7 and/or hydrogen content 8 of the fuel 4 and/or air-fuel mixture 2.

(8) This embodiment comprises a turbocharger 18 consisting of a compressor 16 and a turbine 17.

(9) In this embodiment, the at least one temperature adjusting means 5 comprises an intercooler 9 with a fluid circuit 10 and a fluid temperature controller 19, wherein the fluid temperature controller 19 can be controlled to alter the temperature of the temperature adjusting fluid 11.

(10) In respect to this embodiment of a combustion engine 1, firstly, the air 3 and fuel 4 enter the air-fuel mixing means 15; secondly, the air-fuel mixture 2 is measured by the sensor 12, compressed by the compressor 16 and cooled or heated by the temperature adjusting means 5 before the air-fuel mixture 2 enters the at least one combustion chamber 13; then, the exhaust gas leaves the combustion chamber 13, is decompressed by the turbine 17 of the turbocharger 18 and enters an exhaust aftertreatment system 20, e.g., a three-way catalyst, a SCR catalyst or the like, before it leaves the combustion engine 1.

(11) In this embodiment, the control unit 6 of the combustion engine 1 controls the temperature adjusting means 5 by means of the fluid temperature controller 19.

(12) The control unit 6 uses data for the temperature control 14 mechanism, wherein the data is generated by the at least one sensor 12.

(13) FIGS. 2 and 3 show a first variant of a temperature control 14 mechanism for a combustion engine 1 proposed, wherein FIG. 2 represents the control scheme and FIG. 3 represents the steps that are executed successively to achieve the temperature control 14.

(14) As shown in FIGS. 2 and 4, both variants comprise at least one temperature adjusting means 5 with an intercooler 9 and a fluid circuit 10 with temperature adjusting fluid 11, such as cooling water.

(15) The temperature adjusting means 5 cools or heats the air 3, fuel 4 and/or air-fuel mixture 2 before the air 3, fuel 4 and/or air-fuel mixture 2 enters a combustion chamber 13 of the combustion engine 1. The combustion chamber 13 is not illustrated in FIGS. 2 and 4; the horizontal arrows pointing towards the reference number 13 indicate that the cooled or heated fluid(s) are supplied to the combustion chamber 13

(16) Preferably, the combustion engine 1 comprises multiple temperature adjusting means 5, e.g., two or three intercoolers 9 and/or other temperature adjusting means 5.

(17) If multiple temperature adjusting means 5, particularly multiple intercoolers 9, are used and cooling or heating is performed in stages, it is advantageous to cool or heat the air 3, fuel 4 and/or air-fuel mixture 2 at stages with lower temperatures and/or at the last stage where the temperature of the air 3, fuel 4 and/or air-fuel mixture 2 is the lowest.

(18) Cooling the air 3, fuel 4 and/or air-fuel mixture 2 at the stage with the lowest temperature, the smallest amount of energy is required to achieve the target temperature of the air 3, fuel 4 and/or air-fuel mixture 2 for a present methane number 7 and/or hydrogen content 8.

(19) It is very much preferred that the temperature control 14 is performed in or close to real-time and dependent on the incoming fuel 4 quality.

(20) Preferably, the temperature control 14 mechanism is applied only if required. Preferably, the control unit 6 triggers the temperature control 14 mechanism when the quality of the fuel 4 decreases and/or the engine's operation point moves towards the actual knock resistance.

(21) Decreasing quality of the fuel 4 usually means decreasing methane numbers 4 and/or increasing hydrogen contents 8.

(22) In the first variant, shown in FIGS. 2 and 3, the control unit 6 of the combustion engine 1 is configured to control the temperature of the air 3, fuel 4 and/or air-fuel mixture 2 directly, i.e., by means of direct temperature control 14.

(23) This means that the control unit 6 retrieves the methane number 7 and/or hydrogen content 8 measured by the at least one sensor 12, sets a target temperature of the air 3, fuel 4 and/or air-fuel mixture 2 based on the retrieved methane number 7 and/or hydrogen content 8, and controls the temperature of the temperature adjusting fluid 11 of the temperature adjusting means 5.

(24) The temperature of the temperature adjusting fluid 11 can be controlled via the fluid temperature controller 19, which can comprise at least one mixing valve, radiator, exhauster or the like, and/or by controlling parameters associated with the fluid temperature controller 19, such as rotations of a fan.

(25) FIGS. 4 and 5 show a second variant of a temperature control 14 mechanism for a combustion engine 1 proposed, wherein FIG. 4 represents the control scheme and FIG. 5 represents the steps that are executed successively to achieve the temperature control 14. The second variant differs from the first variant of FIGS. 2 and 3 in that the control unit 6 is configured to control the temperature adjusting fluid 11 of the temperature adjusting means 5, i.e., by means of indirect temperature control 14.

(26) This means that in the variant shown in FIGS. 4 and 5, the temperature of the air 3, fuel 4 and/or air-fuel mixture 2 is controlled indirectly by means of direct control of the temperature of the temperature adjusting fluid 11, preferably by controlling the fluid temperature controller 19.

(27) This means that the control unit 6 retrieves the methane number 7 and/or hydrogen content 8 measured by the at least one sensor 12, sets a target temperature of the temperature adjusting fluid 11 of the temperature adjusting means 5, and controls the temperature of the temperature adjusting fluid 11 of the temperature adjusting means 5, preferably so that a required or target temperature of the air-fuel mixture 2 inside the combustion chamber 13 can be achieved.

(28) In the schematics, solid lines indicate the flow of the fluids, i.e., air 3, fuel 4 and/or the air-fuel mixture 2; and dashed lines indicate the application of the temperature control 14 mechanism controlled by the control unit 6.

LIST OF REFERENCES

(29) 1 combustion engine 2 air-fuel mixture 3 air 4 fuel 5 temperature adjusting means 6 control unit 7 methane number 8 hydrogen content 9 intercooler 10 fluid circuit 11 temperature adjusting fluid 12 sensor 13 combustion chamber 14 temperature control 15 air-fuel mixing means 16 compressor 17 turbine 18 turbocharger 19 fluid temperature controller 20 exhaust aftertreatment system