DE102004029538A1 - Charging device for internal combustion engines with pulse jet support - Google Patents

Abstract

The invention relates to a charging device (11) having a compressor part (9) and a turbine part (10) for an internal combustion engine (1). The compressor part (9) is associated with an inflow line (8.1) and an outflow line (8.2). The turbine part (10) is acted upon via an exhaust pipe (59) with the exhaust pipe (59) with the exhaust gas of the internal combustion engine (1). Between the compressor-side outflow line (8.2) and the exhaust line (59) to the charging device (11) upstream of the charging device (11) in the exhaust pipe (59) opening pulse jet tube (53) is arranged.

Description

technical area

to Improvement of the cylinder filling with combustion air come on internal combustion engines charging devices for use. The superchargers can be used as exhaust gas turbochargers or mechanically driven loader or be designed as a pressure wave loader and increase in the intake tract of an internal combustion engine the pressure level, at open Inlet valves of the internal combustion engine a higher degree of filling to reach the cylinder. At lower speeds of internal combustion engines occurs in exhaust gas turbochargers on the so-called "turbo lag", since due to the lower exhaust gas flow rate the discharged from the turbine to the compressor impeller of the exhaust gas turbocharger mechanical power for increasing the pressure in the intake tract of the internal combustion engine no longer sufficient.

at Exhaust gas turbochargers which are used on internal combustion engines, be it self-igniting or spark-ignited internal combustion engines, used, occurs in the lower speed range of the internal combustion engine the above already mentioned Turbo lag on. In this operating state of an internal combustion engine extends the exhaust gas flow, that of the internal combustion engine is produced, not to the compressor impeller of the exhaust gas turbocharger to drive at a speed which leads to a sufficient pressure increase in the Intake tract of the internal combustion engine could lead.

A Possible solution, the above-described Betriebscharakteristikum exhaust gas turbochargers To be master, lies in the exhaust gas turbocharger, e.g. electrical To provide drivable Zusatzag gregate, for example, via a One-way clutch from reaching a certain lower speed value the internal combustion engine are switchable and after crossing a certain, the turbo lag avoiding speed of the internal combustion engine can be thrown off again, what about, for example an overrunning clutch or an overrunning clutch or the like can take place.

so trained auxiliary drives on exhaust gas turbochargers increase on the one hand the cost of the exhaust gas turbocharger and on the other hand take a relative huge Space in use, the internal combustion engines in always to a more limited extent disposal stands.

The presented above remedial option therefore a considerable effort in terms of the used Components and in terms of stress additional Space in the engine compartment of an internal combustion engine.

Out the drive technology Pulse-Jet tubes are known. Pulse-Jet pipes are extremely easy and inexpensive built up. In the simplest case, a piece of pipe of a defined length with a combustion chamber at one end is sufficient. The combustion chamber can through a valve, e.g. a check valve from a mixture preparation device upstream of the combustion chamber be separated. In the combustion chamber, an ignition device is provided, which ignited at startup a mixture cloud, so that a pressure wave is induced in the direction of the pipe end, which is a corresponding Thrusting effect. After expansion end of the pressure wave within of the pulse-jet tube passes through that induced in the combustion chamber Negative pressure over that mentioned Valve of the mixture preparation device Fresh mixture in the combustion chamber while the pressure wave runs back into the combustion chamber at the same time, there Subsequently, the fresh mixture is compressed, so that afterwards a renewed ignition of the fresh mixture on the hot returning Exhaust front can be done. Depending on the design in terms of tube length of the Pulse-jet tube and free flow cross-section, this process takes place at a frequency of up to 300 Hz.

Presentation of the invention

According to the invention, it is proposed a charging device for Internal combustion engines, such as e.g. Assign a pulse-jet tube to an exhaust gas turbocharger. Advantageously, the pulse-jet tube is practically barely Moving parts very simple. Compared to an im Intake tract of an internal combustion engine arranged, electrical Additional drive for the charger is hardly required electric power, furthermore builds the invention proposed, attributable to the charger pulse jet tube much easier.

The pulse-jet tube is preferably integrated on the charging device, such as an exhaust-gas turbocharger, for example, so that the upstream side of the pulse-jet tube is acted upon by the downstream side of the compressor, ie with compressor outlet pressure. On the outflow side, the pulse-jet tube opens into the exhaust pipe upstream to the turbine part of an exhaust gas turbocharger of an internal combustion engine. Instead of an exhaust gas turbocharger, a mechanically driven supercharger or a pressure wave supercharger can also be used. The pulse-jet tube can be arranged both perpendicular to the flow axis of the exhaust pipe, as well as inclined thereto. is the pulse-jet tube is received inclined to the exhaust pipe so that the pressure waves leaving the pulse-jet tube are introduced with pulse in the flow direction of the exhaust gas flowing in the exhaust pipe, a significant increase in performance can be achieved on the turbine part of a charging device designed as exhaust gas turbocharger become.

drawing

Based In the drawings, the invention will be described below in more detail.

It shows:

1 a charging system of an internal combustion engine with turbocharger,

2 a pulse-jet tube extending between the compressor outlet side and turbine inlet side of the charging device and opening into the exhaust pipe of the internal combustion engine to the turbine side of the charging device.

variants

1 are the essential components of an internal combustion engine refer.

The internal combustion engine 1 includes a crankcase 2 in which a crankshaft rotates, which can be bent several times and is connected to the connecting rods of the pistons of the internal combustion engine. The control of the internal combustion engine 1 via a central engine control unit 3 ,

The internal combustion engine 1 has an intake tract 4 in which a suction opening 6 assigned, an air mass meter 5 is provided. From the intake 6 flows the sucked combustion air of a charging device 11 in the form of an exhaust gas turbocharger. About the intake 6 sucked air flows into a compressor impeller 9 a compressor part of the charging device 11 to.

In the 1 illustrated charging device 11 is designed as an exhaust gas turbocharger and includes a compressor impeller 9 , which via an exhaust gas turbocharger shaft 12 with a turbine wheel 10 connected is. The turbine wheel 10 (Turbineneil) of the charging device 11 is acted upon via the exhaust gas volume flow of the individual cylinders of the internal combustion engine, ie flows and drives due to the exhaust gas flow through the exhaust gas turbocharger shaft 12 the compressor impeller 9 at.

Outflow side flows through the compressor impeller 9 compressed air to an intercooler 39 to. Downstream of the intercooler 39 is a charge air sensor in the intake air line 41 arranged, which a throttle device 37 is downstream. From the throttle device 37 from the charged, ie compressed air flows to an inlet valve 29 to and in its open state in a combustion chamber 32 the internal combustion engine 1 one. In the cylinder head area of the internal combustion engine 1 is located in the area of the inlet valve 29 a fuel injector 24 that with a fuel rail 33 communicates. The fuel distributor 33 is about a pressure gauge in this prevailing pressure level 35 supervised. The pressure level in the fuel rail 33 is via a high pressure pump 36 maintained, in turn, one-sided with a fuel module with electric fuel pump 38 communicates. Via an exhaust gas recirculation valve 40 For example, the suction line for the charged, ie compressed combustion air at one of the throttle device 37 downstream point of the combustion air are mixed admixed, depending on the degree of opening of an exhaust gas recirculation valve 40 , reference numeral 41 denotes a charge air sensor.

In the cylinder head area of the internal combustion engine 1 is located between the inlet valve 29 and an exhaust valve 30 an ignition coil 28 , Furthermore, located in the cylinder head area of the internal combustion engine 1 a camshaft 25 that is a phase sensor 26 assigned. About the phase sensor 26 lets the phase position of the internal combustion engine 1 detect. The internal combustion engine 1 also includes a flywheel, which is a crankshaft sensor 27 is assigned, via which the speed of the internal combustion engine 1 can be detected. In addition, the internal combustion engine 1 a knock sensor 34 as well as at least one temperature sensor 23 assigned.

In the illustration according to 1 is the charging device 11 designed as an exhaust gas turbocharger whose compressor impeller 9 is charged with air. The trained as exhaust gas turbocharger charging device 11 includes a waste gate 21 , which is actuated via a waste gate actuator.

Outflow side of the charging device 11 in the exhaust pipe 15 a first λ probe 16 and a first catalyst 17 downstream. The first catalyst 17 is another, the main catalyst 18 downstream. Between the first catalyst 17 and the main catalyst 18 there is a temperature sensor 19 , Behind the main catalyst 18 there is another, ie second λ-probe 20 in the exhaust pipe 15 ,

The throttle device 37 that the intercooler 39 in the charge air line is connected by means of the accelerator pedal 14 operated, in the representation according to 1 only schematically indicated and to a switching valve 13 acts.

The representation according to 2 is to take a variant of a pulse-jet tube, which is arranged between the outlet side of the compressor part of the charging device and the inlet of the turbine-side part of the charging device.

From the illustration according to 2 shows that the compressor impeller 9 the charging device 11 over a line 8.1 to the charging device 11 Intake air flows in. The through the compressor impeller 9 compressed air flows over a pipe 8.2 from the charging device 11 from. The administration 8.2 at the outlet side of the compressor part of the charging device 11 has a branch 54 , About the branch 54 flows into a pulse-jet tube 53 at the entrance 51 according to the speed of the compressor impeller 9 precompressed air too. The inlet pressure P _{PJ, ON} essentially corresponds to the outlet pressure of the compressor P _{V, A.} Inside the Pulse Jet tube 53 is a pipe section through a first valve 55 and a second valve 56 limited. The resonance tube section of the pulse-jet tube 53 has a free flow cross-section 57 on. Further, the pulse jet tube 53 behind the first valve 55 an ignition device 58 assigned.

The ignition device 58 may be formed, for example, as a glow plug or as a conventional spark plug. The ignition device 58 is arranged such that it immediately downstream of the first valve 55 into the wall of the Pulse Jet tube 53 is admitted. Before the first valve 55 is in the area of the branch 54 from the discharge line 8.2 of the compressor part 9 the charging device 11 a fuel injection point 60 intended. At this is - indicated by the in 2 drawn fuel mist - fuel into the branch 54 injected.

Behind the first valve 55 runs the pulse-jet tube 53 arcuate to the second valve 56 , Behind the second valve 56 extends an outflow area 52 of the pulse-jet tube 53 , which is streamlined, ie designed with rounded edges. About the in 2 shown outflow area 52 the expanding pressure waves flow into the exhaust pipe 59 one. The outflow area 52 of the pulse-jet tube 53 is such that the out of the combustion chamber of the pulse jet tube 53 exiting expanding pressure waves with a minimized proportion of crossflow velocity in the exhaust pipe 59 enter and the turbine wheel 10 the charging device 11 flow to.

The functioning of the in 2 shown Pulse Jet Boosters is as follows. About the branch 54 from the discharge line 8.2 of the compressor impeller 9 the charging device 11 flows into the entrance 51 of the pulse-jet tube 53 pre-compressed intake air. The not in the branch 54 entering proportion of the pre-compressed intake air flows through the discharge line 8.2 the in 2 not shown, however 1 removable intake tract 4 the internal combustion engine 1 to. By the fuel mist injected into the pre-compressed intake air (cf. 60 ) is in front of the first valve 55 of the Pulse Jet Booster 50 an ignitable mixture is available. This ignitable mixture flows when the first valve is open 55 in the pump-like, between the first valve 55 and the second valve 56 extending combustion chamber. During the influx of the ignitable mixture from the branch 54 over the opened first valve 55 is the second valve 56 , which the outflow area 52 of the pulse-jet tube 53 forms, closed. That over the opened first valve 55 in the example formed spherical combustion chamber ignitable mixture is through the ignition device 58 Ignited (spark plug or glow plug), so that one to the second valve 56 propagating pressure wave arises. After expansion end of the pressure wave in the combustion chamber of the pulse-jet tube 53 behind the first valve 55 pulls the pressure wave through the vacuum induced in the combustion chamber via the first valve 55 Fresh mixture (ie ignitable mixture) from the branch 54 in the combustion chamber, while the pressure wave is retracted simultaneously into the combustion chamber and subsequently via the open first valve 55 inflowing fresh mixture compressed so that then again an ignition of the fresh mixture takes place at the hot returning exhaust front of the pressure wave.

The second valve 56 reaching pressure wave front passes through the second valve 56 in the outflow area 52 of the pulse-jet tube 53 out and compresses that in the exhaust pipe 59 over the exhaust valves 30 the internal combustion engine 1 Exiting exhaust, which is the turbine wheel 10 the charging device 11 flows in. To that in the exhaust pipe 59 the compressor impeller 10 the charging device 11 To impart the highest possible momentum to flowing exhaust gas is the outflow area 52 of the pulse-jet tube 53 tilted as much as possible to the cross flow fraction of the in the exhaust pipe 59 to keep the incoming pressure wave low. The pressure with which the expanding pressure wave from the combustion chamber 53 of the pulse-jet tube is indicated by p _{P, J.} The first valve 55 and the second valve 56 are in terms of their closing surfaces are dimensioned such that they the free flow cross-section 57 of the arcuately curved pulse-jet tube 53 close. The free flow cross section 57 indicates the cross section of a to a combustion chamber of the arcuately curved pulse-jet tube 53 subsequent resonance tube. The combustion chamber of the Pulse Jet tube 53 is in contrast to the free flow cross section 57 in a significantly enlarged diameter designed area of the pulse-jet tube, starting behind the first valve 55 along the ignition source 58 extends and into the resonance tube, which has the free flow cross-section 57 has, flows. Through the first valve 55 is an encapsulation of the combustion chamber against the branch 54 ie against the inlet side and through the second valve 56 against the exit side, ie the outflow area 52 given. The first valve 55 as well as the second valve 56 can have a two valves 55 . 56 common control device 63 be operated.

About the controller 63 can be the first valve 55 and the second valve 56 be activated actively. However, it is also possible, the two valves, ie the first valve 55 and the second valve 56 as passive valves, such as as pure check valves to train. With an active control of the two valves 55 . 56 via the common control device 63 can be the first valve 55 be constantly driven oscillating, while the second valve 56 during operation of the pulse-jet tube 53 is open and inactive pulse-jet tube 53 closed is. Pressure wave surges in the outlet region of the internal combustion engine can disturb the flow within the pulse-jet tube 53 come. This circumstance is prevented by the fact that the second valve 56 of the pulse-jet tube 53 over the two valves 55 . 56 common control device is operated oscillating.

The in the tube section of the pulse-jet tube 53 between the first valve 55 and the second valve 56 reciprocating pressure waves emerge on the outlet side with an outlet pressure P _{PJ, OFF} from the pulse-jet tube 53 out and into an exhaust pipe 59 one. In the exhaust pipe 59 be from the cylinders of the internal combustion engine to the exhaust valves 30 discharged gases collected and the turbine impeller 10 (Turbineneil) of the charging device 11 fed. The charging device 11 has - as in 2 indicated schematically - via a waste gate 21 , via which exhaust gas into the exhaust pipe 15 can be derived.

The pressure build-up within the pulse-jet tube 53 essentially turns itself on automatically, even if the pulse-jet tube 53 without closed second valve 56 is designed. That the Pulse Jet tube 53 at the end of the resonance tube section occlusive second valve 56 can also be omitted; In this case, however, precautions must be taken to prevent exhaust gas entry or disruption of the flow within the pulse-jet tube 53 To prevent by shocks in the exhaust stream of the internal combustion engine.

1

Internal combustion engine

2

crankcase

3

Engine control unit

4

intake system

5

Air flow sensor

6

suction

8.1

management to the charging device

8.2

management of charging device

9

Compressor impeller (Compressor)

10

A turbine rotor (Turbine)

11

charging

12

wave

13

switching valve

14

accelerator Internal combustion engine

15

exhaust pipe

16

first λ probe

17

first catalyst

18

main catalyst

19

temperature sensor

20

second λ probe

21

Wastegate with actuator

23

temperature sensor

24

fuel injector

25

camshaft (Trucks)

26

phase sensor

27

crankshaft sensor

28

ignition coil

29

intake valve

30

outlet valve

31

piston

32

combustion chamber

33

Fuel distributor

34

knock sensor

35

pressure gauge (Fuel-Rail)

36

high pressure pump

37

throttling device

38

tank with electric fuel pump

39

intercooler

40

Exhaust gas recirculation valve

41

Charge air sensor

51

entry

52

exit

53

Pulse jet pipe

54

junction CDP

55

1. Valve

56

Second Valve

57

Flow area

(Resonance tube portion)

58

ignition source

59

exhaust pipe

60

Fuel injection

61

Exhaust gas recirculation line

62

sensor

63

control device for 1. and 2nd valve

P _{V, E}

Compressor inlet pressure

P _{V, A}

CDP

P _{T, E}

Turbine inlet pressure

P _{T, A}

Turbine outlet pressure

P _{PJ, ON}

inlet pressure Pulse jet pipe

P _{PJ, AUS}

CDP Pulse jet pipe

Claims (11)

Charger ( 11 ) with a compressor part ( 9 ) and a turbine part ( 10 ) for an internal combustion engine ( 1 ), wherein the compressor part ( 9 ) an inflow line ( 8.1 ) and a discharge line ( 8.2 ) and the turbine part ( 10 ) via an exhaust pipe ( 59 ) with the exhaust gas of the internal combustion engine ( 1 ) is acted upon, characterized in that between the compressor-side discharge line ( 8.1 ) and the exhaust pipe ( 59 ) to the charging device ( 11 ) an upstream of the charging device ( 11 ) in the exhaust pipe ( 59 ) pulse Pulse Jet tube ( 53 ) is arranged. Charging device according to claim 1, characterized in that the pulse jet tube ( 53 ) on the inflow side with the discharge line ( 8.2 ) of the compressor part ( 9 ) connected is. Charging device according to claim 1, characterized in that the pulse jet tube ( 53 ) upstream of a first valve ( 55 ) and downstream a second valve ( 56 ). Charging device according to claim 1, characterized in that the pulse jet tube ( 53 ) an ignition device ( 58 ). Charging device according to claim 4 , characterized in that the ignition device ( 58 ) is designed as a spark plug or as a glow plug. Charging device according to claim 1, characterized in that a portion of the pulse-jet tube ( 53 ) by one or both valves ( 55 . 56 ) is closable on the inflow side and / or outflow side or on the inflow and outflow side. Charging device according to claim 1, characterized in that the pulse jet tube ( 53 ) inclined to the exhaust pipe ( 59 ) and the outflow-side mouth in the flow direction of the in the exhaust pipe ( 59 ) flowing exhaust gas points. Charging device according to claim 1, characterized in that the pulse jet tube ( 53 ) of the pulse jet booster ( 50 ) between a branch ( 54 ) from the discharge line ( 8.2 ) of the compressor impeller ( 9 ) of the charging device ( 11 ) arcuate to the discharge area ( 52 ) of the pulse-jet tube ( 53 ) in the exhaust pipe ( 59 ). Charging device according to claim 1, characterized in that the branch ( 54 ) to the entrance ( 51 ) of the pulse-jet tube ( 53 ) a fuel injection point ( 60 ) is assigned to which fuel in the compressor-side pre-compressed air before the first valve ( 55 ) of the pulse jet booster ( 50 ) is injected. Charging device according to claim 4, characterized in that the ignition device ( 58 ) in the flow direction of the fresh mixture through the pulse-jet tube ( 53 ), immediately downstream of the first valve ( 55 ) is arranged. Charging device according to claim 1, characterized in that the pulse jet tube ( 53 ) an enlarged in the flow cross section formed as a combustion chamber area with an ignition source ( 58 ) and has a subsequent resonant tube section, softer compared to the flow cross-section of the combustion chamber region of the pulse-jet tube ( 53 ) in a reduced free flow area ( 57 ) is trained.