Claims:We claim:

1. An exhaust system (100) for common-rail fuel injection diesel engine and having electrically controlled turbocharger (130) with integrated exhaust manifold (140), wherein for obtaining the maximum energy transfer, said turbocharger (130) is configured for anti-clockwise rotation of the turbine wheel thereof when viewed from the front of the engine by means of said single smooth integrated exhaust manifold (140).

2. Exhaust system (100) for common-rail fuel injection diesel engine as claimed in claim 1, wherein said integrated exhaust manifold (140) comprises a plurality of runners configured by combining into a single smooth exhaust gas passage (162) for the exhaust gases just after exiting the respective exhaust inlet ports to reduce the pressure drop to a minimum, during the exhaust gas flow therethrough for maximum energy transfer to said turbine wheel.

3. Exhaust system (100) for common-rail fuel injection diesel engine as claimed in claim 1, wherein said engine is a three-cylinder, common-rail direction fuel-injection diesel engine.

4. Exhaust system (100) for common-rail fuel injection diesel engine as claimed in claim 1, wherein said integrated exhaust manifold comprises an exhaust gas passage (150) connected to Exhaust Gas Regenerator (EGR).

5. Exhaust system (100) for common-rail fuel injection diesel engine as claimed in claim 3, wherein said integrated exhaust manifold (140) comprises three exhaust gas inlets (I1, I2, I3) from a respective cylinder thereof and connected via a respective smooth profiled section to said single exhaust gas passage (162) smoothly merging with the inlet of said turbocharger (130) by an anti-clockwise profiled section for obtaining the maximum energy transfer by reducing the pressure drop therein to a minimum.
6. Exhaust system (100) for common-rail fuel injection diesel engine as claimed in claim 1, wherein said integrated exhaust manifold (140) comprises a shorter intercooler hose length for a more compact packaging of said engine with respect to the vehicle interface.

7. Exhaust system (100) for common-rail fuel injection diesel engine as claimed in claim 1, wherein said exhaust system comprises:

• a cylinder head (110) with three cylinders disposed therein;
• an electronic actuator (120), a compressor housing (122), a central bearing housing (124), a lever (126), and a flap valve (128);
• compact turbocharger (130);
• an exhaust manifold (140) integrated thereto;
• a respective exhaust gas inlet (I1, I2, I3) connected to said exhaust gas manifold (140);
• said turbocharger (130) and said exhaust gas manifold (140) are connected to each other by means of a smooth exhaust gas passage (162);
• said exhaust gas passage (162) leads three inlets from a respective cylinder thereof and connected via a respective smooth profiled section to said single smooth exhaust gas passage which merges with the inlet of said turbocharger by means of an anti-clockwise profiled section when viewed from the front of the engine;
• a turbine housing (170) with a turbine wheel;

wherein said turbine wheel is rotated in anti-clockwise direction by means of the exhaust gases received via said smooth exhaust gas passage (162) for obtaining the maximum energy transfer by reducing the pressure drop therein to a minimum.

8. Exhaust system (100) for common-rail fuel injection diesel engine as claimed in claim 7, wherein said smooth exhaust gas passage (162) comprises:

• a respective exhaust gas inlet (I1, I2, I3) connected via a respective exhaust gas pipe to each cylinder of said engine;
• a drain (115) for said turbocharger (130);
• an air inlet (125) from an air filter;
• a shorter passage (145) leading to resonator and intercooler; and
• a passage to the Exhaust gas Aftertreatment System (EATS);

wherein said integrated exhaust manifold (140) comprises an exhaust gas passage (150) connected to Exhaust Gas Regenerator (EGR) via an EGR port.

9. Exhaust system (100) for common-rail fuel injection diesel engine as claimed in claim 8, wherein the merging of said smooth profiled section of integrated exhaust manifold (130) with the inlet of said turbocharger (140) by means of single smooth exhaust gas passage (162) is configured to reduce the pressure drop therein by 30 to 40% as compared to stepped merger of conventional manifold (30) and turbocharger (40).

10. Exhaust system (100) for common-rail fuel injection diesel engine as claimed in claim 9, wherein said smooth exhaust gas passage (162) of said integrated manifold (140) is configured to keep the peak temperatures thereof within the limiting temperature of the material of said integrated manifold (140).

11. Exhaust system (100) for common-rail fuel injection diesel engine as claimed in claim 9, wherein said integrated manifold (140) is made of a material preferably having a limiting temperature of 8000C.

Dated this 24th day of July 2019.

Digitally Signed.

(SANJAY KESHARWANI)
REGN. NO. IN/PA-2043.
APPLICANT’S PATENT AGENT , Description:FIELD OF INVENTION

The present invention relates to an exhaust system for a diesel engine with an integrated exhaust manifold. In particular, the present invention relates to an improved exhaust system for a diesel engine with common rail fuel injection which facilitates a smooth passage of exhaust gases. More particularly, the present invention relates to an exhaust system for common-rail fuel-injection diesel engine and having electrically controlled turbocharger with integrated manifold.

BACKGROUND OF THE INVENTION

The turbocharger in an internal combustion engine is powered by a turbine driven by the exhaust gases of the engine. At present, these turbine wheels are rotated in a clockwise direction. Due to presence of intercooler and air-filter, the length of piping required is substantially higher and therefore the packaging thereof in the engine becomes critical.

DISADVANTAGES OF THE PRIOR ART

In conventional exhaust systems, the turbocharger is powered by a turbine driven with turbine wheels rotating in clockwise direction when viewed from the engine’s front end. The presence of intercooler and air-filter also increases the required piping length and critically impairs a good packaging thereof within the engine and also leads to higher pressure drop in exhaust gas passage thereof.

Therefore, there is an existing need for an improved exhaust gas system having a turbocharger with turbine wheels thereof rotating in anti-clockwise direction. This exhaust system should also include this turbocharger with integrated exhaust manifold for smooth exhaust gas movement to facilitate lower pressure drop in the exhaust gas passage thereof.
OBJECTS OF THE INVENTION

Some of the objects of the present invention - satisfied by at least one embodiment of the present invention - are as follows:

An object of the present invention is to provide an improved exhaust gas system for a diesel engine with integrated exhaust manifold for a smooth exhaust gas flow.

Another object of the present invention is to provide an improved exhaust gas system for a diesel engine with electrically controlled turbocharger.

Still another object of the present invention is to provide an improved exhaust gas system for a diesel engine with the turbine rotation suitable for maximize energy transfer to turbine wheel.

Yet another object of the present invention is to provide an improved exhaust gas system for a diesel engine which minimizes the pressure drop during the exhaust gas flow through the exhaust gas manifold.

A further object of the present invention is to provide an improved exhaust gas system for a diesel engine which reduces the required piping length for better the packaging thereof within the engine.

A still further object of the present invention is to provide an improved exhaust gas system for a diesel engine with smoother flow path and reduced thermally stressed zones with temperatures spread uniformly.

These and other objects and advantages of the present invention will become more apparent from the following description, when read with the accompanying figures of drawing, which are however not intended to limit the scope of the present invention in any way.
DESCRIPTION OF THE INVENTION

The present invention comprises an exhaust system for a diesel engine with common-rail fuel injection and equipped with a turbocharger configured for turbine wheel rotation in anti-clockwise direction when viewed from the front-end of the engine, and an integrated manifold.

This is done to achieve a significantly smoother exhaust gas passage than that available in the conventional exhaust gas systems. Here, exhaust gas is moved through a smooth passage in the exhaust manifold just after exiting from the exhaust ports.

Accordingly, the runners of the exhaust manifold are configured to pass exhaust gases smoothly on the turbine wheel of the turbocharger. Here, the turbine wheel is rotated anti-clockwise to obtain maximum energy transfer. This also restricts the overall pressure drop to a minimum value during the exhaust gas flow through the exhaust gas manifold.

SUMMARY OF THE INVENTION

In accordance with an embodiment of the present invention, there is provided an exhaust system for common-rail fuel injection diesel engine and having electrically controlled turbocharger with integrated exhaust manifold, wherein for obtaining the maximum energy transfer, the turbocharger is configured for anti-clockwise rotation of the turbine wheel thereof when viewed from the front of the engine by means of the single smooth integrated exhaust manifold.

Typically, the integrated exhaust manifold comprises a plurality of runners configured by combining into a single smooth exhaust gas passage for the exhaust gases just after exiting the respective exhaust inlet ports to reduce the pressure drop to a minimum, during the exhaust gas flow therethrough for maximum energy transfer to the turbine wheel.

Typically, the engine is a three-cylinder, common-rail direction fuel-injection diesel engine.

Typically, the integrated exhaust manifold comprises an exhaust gas passage connected to Exhaust Gas Regenerator (EGR).

Typically, the integrated exhaust manifold comprises three exhaust gas inlets from a respective cylinder thereof and connected via a respective smooth profiled section to the single exhaust gas passage smoothly merging with the inlet of the turbocharger by an anti-clockwise profiled section for obtaining the maximum energy transfer by reducing the pressure drop therein to a minimum.

Typically, the integrated exhaust manifold comprises a shorter intercooler hose length for a more compact packaging of the engine with respect to the vehicle interface.

Typically, the exhaust system comprises:

• a cylinder head with three cylinders disposed therein;
• an electronic actuator, a compressor housing, a central bearing housing, a lever, and a flap valve;
• compact turbocharger;
• an exhaust manifold integrated thereto;
• a respective exhaust gas inlet connected to the exhaust gas manifold;
• the turbocharger and the exhaust gas manifold are connected to each other by means of a smooth exhaust gas passage;
• the exhaust gas passage leads three inlets from a respective cylinder thereof and connected via a respective smooth profiled section to the single smooth exhaust gas passage which merges with the inlet of the turbocharger by means of an anti-clockwise profiled section when viewed from the front of the engine;
• a turbine housing with a turbine wheel;

wherein the turbine wheel is rotated in anti-clockwise direction by means of the exhaust gases received via the smooth exhaust gas passage for obtaining the maximum energy transfer by reducing the pressure drop therein to a minimum.

Typically, the smooth exhaust gas passage comprises:

• a respective exhaust gas inlet connected via a respective exhaust gas pipe to each cylinder of the engine;
• a drain for the turbocharger;
• an air inlet from an air filter;
• a shorter passage leading to resonator and intercooler; and
• a passage to the Exhaust gas Aftertreatment System (EATS);

wherein the integrated exhaust manifold comprises an exhaust gas passage connected to Exhaust Gas Regenerator (EGR) via an EGR port.

Typically, the merging of the smooth profiled section of integrated exhaust manifold with the inlet of the turbocharger by means of single smooth exhaust gas passage is configured to reduce the pressure drop therein by 30 to 40% as compared to stepped merger of conventional manifold and turbocharger.

Typically, the smooth exhaust gas passage of the integrated manifold is configured to keep the peak temperatures thereof within the limiting temperature of the material of the integrated manifold.

Typically, the integrated manifold is made of a material preferably having a limiting temperature of 8000C.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The present invention will be briefly described in the following with reference to the accompanying drawings.

Figure 1 shows an exhaust gas system of an internal combustion engine, preferably for a 3-cylinder diesel engine having common-rail fuel injection, which is configured with an electrically controlled turbocharger and an exhaust manifold integrated thereto in accordance with the present invention.

Figure 2a-2b show a front end views of exhaust gas system having a compact turbocharger with integrated exhaust manifold configured in accordance with the present invention to provide smooth passage for gas flow, heat shield mountings, e-actuator for precise control of valve opening & closing and for resonator mounting.

Figure 3a shows an exploded perspective view of the exhaust gas system with compact turbocharger having integrated exhaust manifold shown in Figs. 1-2b.

Figure 3b shows a top view of the exhaust gas system with compact turbocharger having integrated manifold of Fig. 3a and fitted with an e-actuator.

Figure 3c shows a detailed cross-sectional view of the exhaust gas passage of the exhaust gas system sectioned across section line A-A shown in Fig. 3b.

Figure 3d shows another view of the compact turbocharger having integrated exhaust manifold shown in Fig. 3a.

Figure 4 shows another enlarged detailed view of the exhaust gas passage through the exhaust gas system with a compact integrated manifold and turbocharger shown in Figure 1 and Figures 3a-3d depicting the anticlockwise exhaust gas flow to obtain the maximum energy transfer to the turbine wheel in accordance with the present invention.

Figures 5a-5c show a temperature plot of the exhaust gas passage of the exhaust gas system shown in Figure 3a indicating the various views of the temperature prevailing at different portions thereof.

Figures 6a-6b show the pressure drop comparison in the combined conventional manifold and the integrated manifold configured in accordance with the present invention by means of the overlap of the exhaust manifold cores, i.e. gas flow path therein.

Figure 7 shows a comparative bar chart showing the pressure drop at different inlets of the conventional manifold and the integrated manifold configured in accordance with the present invention.

Figures 8a-8c show a comparison of the velocity profile during the exhaust stroke of cylinders 1, 2 and 3 of the conventional manifold (LHS) and of integrated manifold (RHS) configured in accordance with the present invention.

DETAILED DESCRIPTION OF THE ACCOMPANYING DRAWINGS

In the following a single cylinder naturally aspirated diesel engine with SCR technology configured in accordance with the present invention will be described in more details with reference to the accompanying drawings without limiting the scope and ambit of the present invention.

Figure 1 shows an exhaust gas system 100 of an internal combustion engine, preferably for a 3-cylinder diesel engine 150 with common-rail fuel injection and configured with an electrically controlled turbocharger having an exhaust manifold integrated thereto and configured in accordance with the present invention. It shows the cylinder head 110, electric actuator 120 of the compact turbocharger 130 and an integrated exhaust manifold 140 having smooth runners for smooth passage of the exhaust gas onto the turbocharger wheel rotating in an anticlockwise direction. This electric actuator 120 checks the current position of the valve (Feedback sensor) and captures the input signal from ECU and correspondingly actuates.

Since electric actuators are precise and operate without any delay/time lag during immediate requirement of boost. Although, the cost of electric actuators is higher than the conventional actuators, e-actuators are preferred considering the cost/benefit ratio thereof. Here, the control logic algorithm and diagnostic features of electric actuator 120 is incorporated in the engine ECU.

Figure 2a shows a front end view of compact turbocharger 130 having integrated exhaust manifold 140 configured in accordance with the present invention, which provides smooth passage for gas flow, heat shield mountings, e-actuator 120 for precise control of valve opening and closing and for resonator mounting.

Figure 2b shows another front end view of the compact turbocharger 130 having integrated exhaust manifold 140 shown in Fig. 2a.

Figure 3a shows an exploded perspective view of the exhaust system 100 with a compact turbocharger 130 having integrated exhaust manifold 140 shown in Figures 1-2a-2b. Exhaust gas from three (3) cylinders of the cylinder head 110 enters inlets I1, I2 and I3 thereof and an internal passage or outlet O leading to the exhaust gas recirculation (EGR) 160. The exhaust system 100 includes an electronic actuator 120, a compressor housing 122, a central bearing housing 124, a lever 126, flap/valve 128 and a turbine housing 170.

Figure 3b shows a top view of the exhaust system 100 with a compact turbocharger 130 having integrated exhaust manifold 140 shown in Fig. 3a and fitted with e-actuator 120. Cylinder head 110 is mounted with a mounting 112 and an integrated manifold and turbocharger 130, further details of which are shown in Fig. 3b through a sectional view across section line A-A.

Figure 3c shows a detailed view of the exhaust system 100 with a compact turbocharger 130 having integrated manifold shown in Fig. 3a indicating the cylinder head 110, turbocharger 130, integrated manifold 140 and turbocharger oil supply channel 166.

Figure 3d shows another detailed cross-sectional view of the exhaust system 100 with a compact turbocharger 130 having integrated manifold 140 and sectioned across section line A-A shown in Fig. 3b. It shows an exhaust gas passage from the exhaust port to the exhaust manifold. This exhaust gas passage includes cylinder head 110, turbocharger drain 115, air inlet 125 from air filter, passage 145 to resonator and intercooler and a passage 155 to exhaust aftertreatment system (EATS), and exhaust gas passage 162 from the cylinder head 110. It also shows the exhaust manifold runner 140 configured significantly smoother and exhaust ports 164 as well as EGR port 150 therein.

Figure 4 shows another enlarged detailed view of the exhaust gas system 100 with exhaust gas passage through a compact turbocharger 130 having integrated exhaust manifold 140, clearly depicting gas flow passage 162 in anticlockwise direction to obtain the maximum energy transfer to turbine wheel.

Figure 5a shows a temperature plot of the front view of the compact turbocharger 130 having integrated manifold 140 shown in Fig. 3a and indicating the temperatures prevailing at different portions, e.g. at inlets I1, I2 and I3 and at internal passage/outlet O to the exhaust gas recirculation (EGR). The selected material has a temperature limit of 8000C and the peak temperature here is 7200C, well within material temperature limit of 8000C.

Figure 5b shows a perspective view of the compact turbocharger 130 having integrated manifold 140 shown in Fig. 5a to indicate temperatures prevailing at different portions thereof. Here also, the peak temperature is around 7200C, well within material temperature limit of 8000C.

Figure 5c shows a temperature plot of the compact turbocharger 130 having integrated manifold 140 shown in Fig. 5a to indicate temperatures prevailing at different portions thereof. The peak temperature is again around 7200C, well within material temperature limit of 8000C. From Figures 5a to 5c, it is clear that temperatures are spread uniformly, and the maximum or peak temperature is around 7200C by smoother flow path and reduced thermally stressed zones.

Figure 6a shows the pressure drop comparison in the combined conventional manifold 30 and the integrated manifold 130 configured in accordance with the present invention, by means of the overlap of the exhaust manifold cores, i.e. gas flow path therein, both of which are depicted in their side view. In conventional manifold 30, there is a step formed adjacent the zone near the merger of manifold 30 and turbocharger 40, thus causing the highest pressure-drop.

Figure 6b shows pressure drop comparison in the combined conventional manifold 30 and the integrated manifold 130 configured in accordance with the present invention, by means of the overlap of the exhaust manifold cores, i.e. gas flow path therein, both of which are depicted in their side view. In conventional manifold 30, there is a step formed adjacent the zone near the merger of manifold 30 and turbocharger 40, causing the highest pressure-drop. However, with integrated manifold 130 configuration, almost 30-40% pressure drop is reduced as intermediate merging is eliminated and flow is smooth.
Figure 7 shows a comparative bar chart showing the pressure drop at different inlets I1, I2 and I3 of the conventional manifold and integrated manifold configured 30 in accordance with the present invention. Here, the pressure drops at exhaust inlets I1, I2 and I3 of integrated manifold 30 according to the present invention are respective 40.35%, 43.10% and 34.33% lower than in the conventional manifold. With integrated manifold, almost 30-40% pressure drop is reduced since intermediate merging is eliminated and flow becomes smooth.

Figure 8a shows a comparison of the velocity profile during exhaust stroke of cylinder 1 of conventional manifold 30 and integrated manifold 130 configured according to the present invention. This velocity streamline profile comparison shows laminar and smooth flow with reduced turbulence with integrated manifold configuration compared with conventional design.

Figure 8b shows a comparison of the velocity profile during the exhaust stroke of cylinder 2 of conventional manifold 30 and integrated manifold 130 configured according to the present invention. This velocity streamline profile comparison shows laminar and smooth flow with reduced turbulence with integrated manifold configuration compared with conventional design.

Figure 8c shows a comparison of the velocity profile during exhaust stroke of cylinder 3 of the conventional manifold 30 and integrated manifold 130 configured according to the present invention. This velocity streamline profile comparison shows laminar and smooth flow with reduced turbulence by integrated manifold 130 as compared with conventional manifold 30.

TECHNICAL ADVANTAGES AND ECONOMIC SIGNIFICANCE

The exhaust gas system of an internal combustion engine, e.g. a 3-cylinder diesel engine with common-rail fuel injection and with electrically controlled turbocharger having integrated exhaust manifold configured in accordance with the present invention offers the following advantages:

• Compact packaging w.r.t. vehicle interface by reducing the intercooler hose length.

• Minimum loss of energy of the exhaust gas before reaching turbine wheel.

• Better turbocharger performance.

• Minimum pressure-drop while exhaust gas flows through the exhaust gas manifold due to smooth runners provided therein.

The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments.

It is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation. The exemplary embodiments described in this specification are intended merely to provide an understanding of various manners in which this embodiment may be used and to further enable the skilled person in the relevant art to practice this invention.

Although, the embodiments presented in this disclosure have been described in terms of its preferred embodiments, the skilled person in the art would readily recognize that these embodiments can be applied with modifications possible within the spirit and scope of the present invention as described in this specification. Accordingly, the skilled person can make innumerable changes, variations, modifications, alterations and/or integrations in terms of materials and method used to configure, manufacture and assemble various constituents, components, subassemblies and assemblies, in terms of their size, shapes, orientations and interrelationships without departing from the scope and spirit of the present invention.

The numerical values given of various physical parameters, dimensions and quantities are only approximate values and it is envisaged that the values higher or lower than the numerical value assigned to the physical parameters, dimensions and quantities fall within the scope of the disclosure unless there is a statement in the specification to the contrary.

Throughout this specification, the word “comprise”, or variations such as “comprises” or “comprising”, shall be understood to imply including a described element, integer or method step, or group of elements, integers or method steps, however, does not imply excluding any other element, integer or step, or group of elements, integers or method steps.

The use of the expression “a”, “at least” or “at least one” shall imply using one or more elements or ingredients or quantities, as used in the embodiment of the disclosure in order to achieve one or more of the intended objects or results of the present invention.

The description of the exemplary embodiments is intended to be read in conjunction with the accompanying drawings, which are to be considered part of the entire written description. In the description, relative terms such as “lower”, “upper”, “horizontal”, “vertical”, “above”, “below”, “up”, “down”, “top”, and “bottom” as well as derivatives thereof (e.g. “horizontally”, “downwardly”, “upwardly” etc.) should be construed to refer to the orientation as then described or as shown in the drawing under discussion.

These relative terms are for convenience of description and do not require that the corresponding apparatus or device be constructed or operated in a particular orientation. Terms concerning attachments, coupling and the like, such as “connected” and “interconnected”, refer to a relationship, wherein structures are secured or attached to one another either directly or indirectly through intervening structures, as well as both movable or rigid attachments or relationships, unless expressly described otherwise.