CN112041554A

CN112041554A - Air inlet circuit connector

Info

Publication number: CN112041554A
Application number: CN201980028102.5A
Authority: CN
Inventors: N·德莱福特里; T·维尼齐亚尼
Original assignee: Renault SAS
Current assignee: Renault SAS
Priority date: 2018-04-25
Filing date: 2019-04-15
Publication date: 2020-12-04
Anticipated expiration: 2039-04-15
Also published as: EP3784898A1; FR3080654B1; CN112041554B; KR20210002572A; FR3080654A1; WO2019206717A1; JP2021522439A

Abstract

The invention relates to an intake circuit connector, in particular for a heat engine of a motor vehicle, comprising a tubular section (3) for fresh air circulation and a flow obturator (5) for regulating the air circulation, characterized in that a duct (9) for gas circulation projects into the section downstream of and immediately adjacent to the obturator.

Description

Air inlet circuit connector

Technical Field

The present invention relates to an intake circuit connector. The invention also relates to a combustion engine or a heat engine comprising such an intake circuit connector. The invention also relates to a motor vehicle comprising such a combustion engine.

Background

Combustion engines, in particular combustion engines mounted to motor vehicles, require fresh air to run, which is led into the combustion chamber through an air intake circuit. The combustion of the fuel in the combustion chamber produces gases that are exhausted through an exhaust circuit.

Combustion or heat engines typically include an Exhaust Gas Recirculation (EGR) system. Such EGR systems are typically used to reduce polluting emissions and/or to optimize engine power. A greater or lesser proportion (also referred to as EGR ratio) of exhaust gas is redirected from the exhaust circuit of the engine to the air intake circuit. In the remainder of the description, the exhaust gases that are redirected from the exhaust circuit of the engine to the air intake circuit are referred to as EGR gases.

The EGR system makes it possible to reintroduce the gases burnt during the previous combustion into the combustion chamber. Such systems require the EGR gas to be mixed with fresh air. For this purpose, mixers are generally used, referred to as air-EGR mixers in the remainder of the description. However, such mixers are very bulky compared to other elements of the combustion engine. Furthermore, such a mixer can lead to pressure losses in the air intake circuit of the combustion engine.

Disclosure of Invention

The object of the present invention is to provide a system which addresses the above mentioned drawbacks and improves the systems known in the prior art. In particular, the invention proposes a valve system which makes it possible to form a combustion engine which does not comprise an air-EGR mixer.

In order to achieve this object, the invention relates to an intake circuit connector, in particular intended for a heat engine of a motor vehicle, comprising a tubular section intended for the circulation of fresh air and a flow obturator intended for regulating the circulation of air, characterized in that a duct intended for the circulation of gases projects into this section downstream of and immediately adjacent to said obturator.

Advantageously, the conduit intended for the circulation of the gas may open in the upstream direction of the section.

Advantageously, the duct intended for the circulation of the gas can open into the section in a region of high air flow and of strong turbulence generated by the flow obturator.

The protruding opening of the duct may be inclined in the section so as to form an angle between the main direction of the section and the main direction of the duct of between 10 ° and 80 °, in particular between about 10 ° and 80 °, for example about 45 °, in particular such that the second gas stream circulating in the duct is introduced into the first air stream circulating in the tubular section in counter-current flow or counter-current flow.

The flow occluder may have a percentage of closure less than or equal to 90%.

The conduit may protrude into the tubular section with a protruding height, for example less than or equal to one half of the diameter of the tubular section, for example approximately equal to one quarter of the diameter of the tubular section.

The distance from the end of the catheter projecting into the tubular section to the flow occluder in a direction perpendicular to the main direction of the tubular section may for example be less than or equal to half the diameter of the tubular section.

The distance from the end of the catheter projecting into the tubular section to the flow obturator in the main direction of the tubular section may for example be between 0.5 and 2 times the diameter of the flow obturator, for example approximately equal to one half of the diameter of the flow obturator.

The shape of the cross-section of the protrusion of the conduit may be elongated in a plane containing the main direction of the tubular section.

The invention also relates to a combustion engine comprising a connector as defined above.

Finally, the invention relates to a motor vehicle comprising a combustion engine as defined above or a connector as defined above.

Drawings

Fig. 1 schematically illustrates an embodiment of an intake circuit connector.

Fig. 2 schematically shows an intake circuit connector such as that of fig. 1 in operation when no EGR gas is introduced.

Fig. 3 schematically illustrates an intake circuit connector such as that of fig. 1 in operation when EGR gas is introduced.

Detailed Description

The air intake circuit of a combustion engine may comprise an air intake valve intended to regulate the flow of oxidant air into the combustion chamber. The present invention proposes to exploit the presence of such an air intake valve in the engine, thus making it possible to dispense with the use of an air-EGR mixer in the engine. The air intake valve, in addition to its role in regulating the oxidant air flow rate, is also intended to act as a mixer of air and EGR gas. The intake valve then also acts as a valve for metering EGR gas. To this end, a conduit intended to channel EGR gas is directly connected to the air intake valve at a judiciously chosen location. This makes it possible to introduce EGR gas into the air intake circuit while mixing it with fresh air. As a result of this, engines provided with such valves do not require an air-EGR mixer and are therefore particularly reduced in volume.

In the rest of the description, the expression "intake circuit connector" denotes a valve system comprising a conduit, in particular a conduit intended to channel EGR gases.

Fig. 1 schematically shows an embodiment of an intake circuit connector 1. The intake circuit connector 1 comprises a tubular section 3. The tubular section 3 is intended for the circulation or passage of a first fluid, preferably air, more preferably fresh air. The intake circuit connector 1 further comprises a flow obturator 5. The flow obturator 5 is intended to regulate the circulation or flow (called first flow) of a first fluid (for example air) in the tubular section 3. The direction of circulation of the first flow of the first fluid in the tubular section 3 is indicated by the arrow 7. The intake circuit connector 1 further comprises a conduit 9 connected to the tubular section 3 downstream of the flow obturator 5. The conduit 9 projects into the tubular section 3 downstream of and immediately adjacent to the flow obturator 5. The conduit 9 is intended for the circulation of a second fluid, preferably EGR gas, and for introducing the second fluid into the tubular section 3. The direction of circulation of the flow of the second fluid in the conduit 9 (referred to as second flow) is indicated by the arrow 11.

The term "fresh air" is understood to mean air which is introduced into the air intake circuit for the first time, in other words air which has never been previously conveyed into the combustion chamber.

When the first fluid circulates in the tubular section 3, there is an inherent pressure loss in the tubular section 3. Advantageously, the conduit 9 opens into the tubular section 3 downstream of the flow obturator 5 in the region of high air flow and/or pressure losses and/or turbulence or intense turbulence generated by the flow obturator 5. The second fluid is thus introduced into this turbulent flow, which makes it possible to minimize the pressure losses associated with the introduction of the second fluid into the tubular section 3. This also makes it possible to optimize the mixing of the first fluid with the second fluid.

The conduit 9 is connected to the tubular section 3, protruding into the tubular section 3. For example, the conduit 9 is mounted by being punched into the tubular section 3, in other words into the body of the intake circuit connector 1.

The conduit 9 projects into the tubular section 3 with a projection height h. The projecting height h of the conduit 9 in the tubular section 3 is for example less than or equal to half the diameter D of the tubular section 3. Preferably, the height h of projection of the duct 9 in the tubular section 3 is for example approximately equal to a quarter of the diameter D of the tubular section 3.

Advantageously, the conduit 9 opens in the upstream direction of the tubular section 3. Advantageously, the protruding access opening of the duct 9 is inclined in the section 3.

The tubular section 3 extends in a main direction Δ 1. The conduit 9 extends in a main direction Δ 2. The main direction Δ 2 of the conduit 9 forms an angle Φ with the main direction Δ 1 of the tubular section 3.

Advantageously, the conduit 9 is connected to the tubular section 3 such that the main direction Δ 1 of the tubular section 3 and the main direction Δ 2 of the conduit 9 form an angle Φ of between 10 ° and 80 °, in particular of about between 10 ° and about 80 °, preferably of about 45 °. The angle Φ between the main directions Δ 1, Δ 2 of the tubular section 3 and the conduit 9 is chosen such that the second flow of the second fluid circulating in the conduit 9 is introduced in counter-current flow or counter-current manner into the first flow of the first fluid circulating in the tubular section 3. As a result of this, the first and second flows interact, which makes it possible to obtain a mixture between the first and second fluids.

According to one exemplary embodiment, the intake circuit connector 1 comprises an oxidant intake valve and is intended for a combustion engine. The tubular section 3 is intended, for example, for channeling air (e.g. fresh air), in particular for introducing oxidant air. The conduit 9 is for example intended for channelling gases (for example EGR gases). The conduit 9 may also be intended for channeling blow-by gases (which refers to the venting of gases), for example, or for channeling fuel vapors.

Preferably, the valve of the intake circuit connector 1 has a small percentage of closure. This serves in particular to avoid fouling of the intake circuit connector 1 due to the introduction of EGR gas into the tubular section 3.

The expression "percentage of closure" is understood to mean the percentage of closure compared with the open position of the flow obturator 5, corresponding to the rest position. A closing percentage of 0% corresponds to the open position of the flow obturator 5 and a closing percentage of 100% corresponds to the fully closed position of the flow obturator 5.

Advantageously, the percentage of closure of the flow obturator 5 is less than or equal to 90%, preferably less than or equal to 50%, more preferably less than or equal to 20%. Therefore, the intake circuit connector 1 is not easily affected by the fouling.

The distance D1 from the end of the catheter 9 projecting into the tubular section 3 to the flow obturator 5 in a direction perpendicular to the main direction Δ 1 of the tubular section 3 is, for example, less than or equal to half the diameter D of the tubular section 3. Preferably, the distance D1 is for example approximately equal to a quarter of the diameter D of the tubular section 3.

In the main direction Δ 1 of the tubular section 3, the distance D2 from the end of the catheter 9 projecting into the tubular section 3 to the flow obturator 5 is, for example, between 0.5 and 2 times the diameter D5 of the flow obturator 5. Preferably, the distance D2 is for example approximately equal to one half of the diameter D5 of the flow obturator 5. Advantageously, the duct 9 is arranged as close as possible to the turbulent flow zone of the tubular section 3, which is generated by the flow obturator 5.

As shown in fig. 1, the distances d1 and d2 are measured, for example, between the center of the flow obturator 5 and the center of the cross section of the end of the catheter 9 protruding into the tubular section 3.

The shape of the cross-section of the projection of the duct 9 is for example elongated in a plane P which contains the main direction Δ 1 of the tubular section 3 and maximizes the angle formed between this plane and the main direction Δ 2. The diameter of the cross section of the protrusion of the duct 9 is for example about D/5. The shape and size of the cross-section of the protrusion of the conduit 9 will be selected, for example, according to the EGR gas flow demand.

According to an exemplary embodiment, the valve 1 is of the type with a flap. The flow obturator 5 is then for example a flap.

The operation of an intake circuit connector 1 such as that of fig. 1 will be described below with reference to fig. 2 and 3.

Fig. 2 schematically shows the intake circuit connector 1 in operation when no second fluid (e.g. EGR gas) is introduced into the tubular section 3.

The flow obturator 5 is in the open position, in the rest position.

The valve 21, which is not shown in fig. 1 but is shown in fig. 2, is arranged in the conduit 9 upstream of the conduit, that is to say at the end of the conduit 9 opposite the end projecting into the tubular section 3.

The conduit 9 is closed by a valve 21. Thus, the second fluid is not introduced into the tubular section 3.

The arrow 23 indicates a first flow of the first fluid in the tubular section 3. As schematically shown in fig. 2, the presence of the conduit 9 connected to the tubular section 3 and protruding into the tubular section 3 causes only a small pressure loss in the tubular section 3. Thus, the valve 1 functions as if there were no conduit 9.

However, there may be slight air turbulence in the tubular section 3, in particular in the region 25 upstream of the end of the conduit 9 projecting into the tubular section 3.

Advantageously, the projection height h of the duct 9 into the tubular section 3 can be reduced in order to reduce the phenomenon of air turbulence in the tubular section 3. The protrusion height h can be chosen, in particular by balancing the angle Φ between the main directions Δ 1, Δ 2 of the tubular section 3 and the conduit 9, which serves to minimize the phenomenon of air turbulence in the tubular section 3, while ensuring the best quality of mixing between the first and second fluids.

Fig. 3 schematically shows the intake circuit connector 1 in operation when a second fluid, for example EGR gas, is introduced into the tubular section 3.

The flow obturator 5 is inclined at an angle ω with respect to the main direction Δ 1 of the tubular section 3. The angle of inclination ω of the flow obturator 5 with respect to the main direction Δ 1 of the tubular section 3 is, for example, between 0 ° and 20 ° (for example, about 20 °).

The arrow 33 indicates a first flow of the first fluid in the tubular section 3. As illustrated by the arrow 33 in fig. 3, the inclined position of the flow obturator 5 with respect to the main direction Δ 1 of the tubular section 3 generates a pressure loss in the tubular section 3. This creates a reduced pressure zone that allows the introduction of the second fluid into the tubular section 3.

Arrows 35 indicate a second flow of the second fluid in the conduit 9. The conduit 9 makes it possible to introduce the second fluid into the tubular section 3 under aerodynamic disturbance of the first fluid. As illustrated by arrows 37 in fig. 3, after the introduction of the second flow of the second fluid into the tubular section 3, the flow of the first and second fluids downstream of the end of the conduit 9 protruding into the tubular section 3 has a small pressure loss. Thus, the intake circuit connector 1 makes it possible to obtain a homogeneous mixture of the first fluid (which is, for example, air) and the second fluid (for example, EGR gas) at its outlet. Furthermore, the mixing of the first fluid and the second fluid causes a reduction in pressure loss. Thus, the intake circuit connector 1 functions as a mixing valve.

One advantage of an air intake circuit connector, such as the one described with reference to fig. 1-3, is that it acts as a flow regulator for the first fluid and as a mixer for mixing the first and second fluids. When such an intake circuit connector is arranged, for example, in a combustion engine, it makes it possible to dispense with the use of an air-EGR mixer. The outlet of the intake circuit connector produces a homogeneous mixture of the first fluid (which is, for example, air) and the second fluid (which is, for example, EGR gas), while the pressure loss in the intake circuit of the first fluid has been minimized.

Fig. 1 to 3 show the intake circuit connector 1 with the main direction Δ 2 of the conduit 9 positioned in a plane perpendicular to the plane of the flow obturator 5.

The reference α indicates the angle formed between the plane of the flow obturator 5 and the orthogonal projection of the main direction Δ 2 of the duct 9 on a plane perpendicular to the direction Δ 1 when in the rest position, open position. In the exemplary embodiment of fig. 1-3, the angle α is approximately 90 °.

According to a variant, the main direction Δ 2 of the catheter 9 can be positioned in the plane of the flow obturator 5. The angle alpha is then 0 deg.. Any other orientation of the main direction Δ 2 of the catheter 9 relative to the plane of the flow obturator 5 may also be chosen. The value of the angle a should be chosen between 0 ° and 360 ° depending on the geometry of the intake circuit connector upstream of the flow obturator 5. The optimum value of the angle alpha should be determined, for example, by means of aerodynamic calculations.

The invention has been described in relation to fig. 1 to 3 in the case of a valve 1 of the type having a flap. According to a variant, the valve 1 can be of the type with a sliding shutter.

An intake circuit connector, such as the one described with reference to fig. 1 to 3, may be used for the combustion engine (or heat engine) 41. Such an intake circuit connector makes it possible to dispense with the use of an air-EGR mixer in the combustion engine. This results in a more compact combustion engine.

The invention also relates to a motor vehicle 51 comprising such a combustion engine 41 or an intake circuit connector (such as the one described with reference to fig. 1 to 3).

A connector such as the one described with reference to fig. 1 to 3 may be used for any type of application where it is desired to mix two fluids, one of which has a flow regulated by a valve. Such a connector may be used in a boiler, for example.

Claims

1. An intake circuit connector, in particular intended for a heat engine of a motor vehicle, comprising a tubular section (3) intended for fresh air circulation and a flow obturator (5) intended for conditioning air circulation, characterized in that a duct (9) intended for gas circulation projects into this section downstream of and immediately adjacent to the obturator.

2. A connector according to claim 1, characterized in that the conduit (9) intended for the circulation of the gas opens in the upstream direction of the section (3).

3. The connector according to claim 1 or 2, characterized in that the duct (9) intended for the circulation of the gas opens into the section (3) in a region of high air flow and of strong turbulence generated by the flow obturator (5).

4. A connector according to any one of claims 1 to 3, characterized in that the protruding opening of the duct (9) is inclined in the section (3) so as to form an angle (Φ) between the main direction (Δ 1) of the section (3) and the main direction (Δ 2) of the duct (9) of between 10 ° and 80 °, for example of about 45 °, in particular such that the second gas flow circulating in the duct (9) is introduced into the first air flow circulating in the tubular section (3) in counter-current flow or counter-current manner.

5. A connector according to any one of claims 1 to 4, characterized in that the flow obturator (5) has a percentage of closure less than or equal to 90%.

6. A connector according to any one of claims 1 to 5, wherein the conduit (9) projects into the tubular section (3) with a projection height (h) which is less than or equal to one half of the diameter (D) of the tubular section (3), for example approximately equal to one quarter of the diameter (D) of the tubular section.

7. A connector according to any one of claims 1 to 6, characterized in that the distance (D1) from the end of the conduit (9) projecting into the tubular section (3) to the flow obturator (5) in a direction perpendicular to the main direction (Δ 1) of the tubular section (3) is less than or equal to half the diameter (D) of the tubular section (3).

8. The connector according to any one of claims 1 to 7, characterized in that in the main direction (Δ 1) of the tubular section (3), the distance (D2) from the end of the conduit (9) projecting into the tubular section (3) to the flow obturator (5) is between 0.5 and 2 times the diameter (D5) of the flow obturator (5), for example approximately equal to half the diameter (D5) of the flow obturator.

9. Connector according to any one of claims 1 to 8, characterized in that the shape of the cross-section of the projection of the duct (9) is elongated in a plane (P) containing the main direction (Δ 1) of the tubular section (3).

10. A combustion engine (41) comprising a connector according to any one of claims 1-9.

11. A motor vehicle (51) comprising a combustion engine according to claim 10 or a connector according to any of claims 1-9.