Claims:1. A static mixer unit (100) for an exhaust gas system (500) comprising:
a housing (201) configured for guiding exhaust gas from an inlet opening (202) to an outlet opening (203);
a plurality of angularly twisted blades (204) spaced apart from each other are configured inside the housing (201);
a hub (205) configured substantially axially within the housing (201) such that the plurality of angularly twisted blades (204) are mounted between the hub (205) and the housing (201), wherein the exhaust gas impinges an inner wall (205a) of the hub (205) and diffuses fluid particles from the exhaust gas; and
a tray (206) configured to the hub (205) protrudes outwardly at the inlet opening (202) of the housing (201) for accumulating fluid particles diffused from the exhaust gas.

2. The static mixer unit (100) as claimed in claim 1, wherein plurality of angularly twisted blades (204) are fixed and extends from an inner wall (205a) of the housing (201) up to an outer rim (205b) of the hub (205) for deflecting the exhaust gas.

3. The static mixer unit (100) as claimed in claim 1, wherein exhaust gases coming into the inlet opening (202) impinges on an inner wall (205a) of the hub (205) and diffuses fluid particles from the exhaust gas.

4. The static mixer unit (100) as claimed in claim 1, wherein the plurality of angularly twisted blades (204) has an angle of inclination ranging from about 30º to about 70º with respect to a hub axis (A-A).

5. The static mixer unit (100) as claimed in claim 1, wherein each of the plurality of angularly twisted blades (204) is configured with a curved tip end (204a) for creating spiral exhaust gas flow.

6. The static mixer (100) as claimed in claim 1, wherein the hub (205) is provided with an inner wall (205a) for impingement of exhaust gas.

7. The static mixer (100) as claimed in claim 1, wherein the tray (206) is provided with an inclination ranging from about 0º to about 30º with respect to the axis C-C.

8. A method of assembling a static mixer unit (100) comprising steps of:
configuring a housing (201) for guiding exhaust gas from an inlet opening (202) to an outlet opening (203);
configuring a plurality of angularly twisted blades (204) spaced apart from each other inside the housing (201);
configuring a hub (205) substantially axially within the housing (201) such that the plurality of angularly twisted blades (204) are mounted between the hub (205) and the housing (201), wherein the exhaust gas impinges an inner wall (205a) of the hub (205) and diffuses fluid particles from the exhaust gas; and
configuring a tray (206) protruding outwardly at the inlet opening (202) of the housing (201) for accumulating fluid particles diffused from the exhaust gas.
, Description:TECHNICAL FIELD
Present disclosure generally relates to a mixer unit. Particularly but not exclusively relates to a static mixer unit for an exhaust gas system of an internal combustion engine which aids in reduction of harmful elements in the exhaust gas by fluid diffusion.
BACKGROUND OF DISCLOSURE
Internal combustion engines especially, in a diesel engine, the ignition of fuel is taking place by a compression-ignition process. In a compression-ignition process air is compressed up to the ratios of 15:1 and 22:1 [also termed as equivalence ratio] resulting in high pressure and temperatures, leading to ignition of the fuel without the aid of fuel ignition or spark plug. This high compression of the fuel automatically ignites the fuel and hence develops the power stroke in the internal combustion engine. The compression-ignition also leads to increased efficiency of the internal combustion engine. However, during combustion in a diesel engine, the mixing, vaporization, atomization and combustion are all occurring at the same time. Therefore, any imbalances in the fuel supplied to the combustion chamber increases formation of harmful exhaust gases. If the amount of fuel supplied to the combustion chamber is greater than the equivalence ratio, then smoke and soot formation increases. If the fuel supplied is less than that of the equivalence ratio, mono-nitrogen oxides (NOX) are formed. Right after combustion, burnt fuel are exhausted from the engine through the exhaust manifold as exhaust gases. These exhaust gases contain compounds and gases such as Carbon Dioxide (CO2), water (H2O), Nitrogen (N2), Oxygen (O2), Carbon Monoxide (CO) etc., which are exhausted in to the atmosphere. These gases if not treated, will cause harmful environmental effects such as acid rain, photochemical smog phenomena and global warming.
However, emission reducing means and after-treatment devices such as three way catalysts, catalytic converter are mandatorily installed in automobiles which diffuse the exhaust gases before it is exhausted into the atmosphere. Moreover, diesel internal combustion engines are equipped with Exhaust gas recirculation (EGR) or Selective Catalyst Reduction (SCR) devices, which decreases the amount of mono-nitrogen oxides (NOx) exhausted into the atmosphere. The EGR and SCR devices break down the mono-nitrogen oxides (NOx) into Nitrogen (N2) and water (H2O). Such emission reducing devices are not efficient in adequately breaking down the exhaust gases or mono-nitrogen oxides (NOx) into Nitrogen (N2) and water (H2O).
To mitigate the problems in EGR and SCR devices, a mixer unit is installed at the vicinity of exhaust conduit. The mixer unit deflects the exhaust gases, thereby reducing the harmful elements in the exhaust gas. However, the mixer unit does not provide a means for collecting the reduced exhaust particles. This will make the system prone to expel the exhaust gas along with the reduced harmful exhaust elements/particles to the atmosphere.
SUMMARY OF THE DISCLOSURE
The shortcomings of the prior art are overcome and additional advantages are provided through the present disclosure. Additional features and advantages are realized through the techniques of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered a part of the claimed disclosure.

In one embodiment, the present disclosure provides a static mixer unit for an exhaust gas system comprising housing configured for guiding exhaust gas from an inlet opening to an outlet opening. A plurality of angularly twisted blades spaced apart from each other and configured inside the housing. A hub configured substantially axially within the housing such that the plurality of angularly twisted blades are mounted between the hub and the housing, wherein the exhaust gas impinges an inner wall of the hub and diffuses fluid particles from the exhaust gas. A tray configured to the hub protrudes outwardly at the inlet opening of the housing for accumulating fluid particles diffused from the exhaust gas.

In one embodiment, plurality of angularly twisted blades are fixed and extends from an inner wall of the housing up to an outer rim of the hub for deflecting the exhaust gas.

In one embodiment, exhaust gases coming into the inlet opening impinges on an inner wall of the hub and diffuses fluid particles from the exhaust gas.

In one embodiment, the plurality of angularly twisted blades has an angle of inclination ranging from about 30º to about 70º with respect to a hub axis (A-A).

In one embodiment, the plurality of angularly twisted blades have a curved tip end for creating spiral exhaust gas flow.

In one embodiment, the hub is provided with an inner wall for impingement of exhaust gas.

In one embodiment, the tray is provided with an inclination ranging from about 0º to about 30º with respect to the axis C-C.

In one embodiment, a method of assembling a static mixer unit is provided, the method comprising steps of: firstly configuring housing for guiding exhaust gas from an inlet opening to an outlet opening. Secondly, a plurality of angularly twisted blades spaced apart from each other is configured inside the housing. Thirdly, a hub is configured substantially axial within the housing such that the plurality of angularly twisted blades are mounted between the hub and the housing, wherein the exhaust gas impinges an inner wall of the hub and diffuses fluid particles from the exhaust gas. Further, a tray protruding outwardly at the inlet opening of the housing is configured for accumulating fluid particles diffused from the exhaust gas.
The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
The features of the present disclosure will become more fully apparent from the following description and appended claims, taken in conjunction with the accompanying drawings. Understanding that, these drawings depict only several embodiments in accordance with the disclosure and are therefore, not to be considered limiting of its scope. The disclosure will be described with additional specificity and detail through use of the accompanying drawings.

Figure 1 illustrates front view of the static mixer unit according to an exemplary embodiment of the present disclosure.

Figure 2 illustrates perspective view of the static mixer unit according to an exemplary embodiment of the present disclosure.

Figure 3 illustrates static mixer unit installed in an exhaust gas system according to an exemplary embodiment of the present disclosure.

Figures 4 and 5 illustrates side view and perspective views of the static mixer unit during working of the static mixer unit when the spray is mixed with the exhaust gases according to an embodiment of the present disclosure.

The figures depict embodiments of the disclosure for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.

DETAILED DESCRIPTION OF THE DISCLOSURE

In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, similar symbols typically identify similar components, unless context dictates otherwise. The illustrative embodiments described in the detailed description, drawings, and claims are not meant to be limiting. Other embodiments may be utilized, and other changes may be made, without departing from the scope of the subject matter presented herein. It will be readily understood that the aspects of the present disclosure, as generally described herein, and illustrated in the figures, can be arranged, substituted, combined, and designed in a wide variety of different configurations, all of which are explicitly contemplated and make part of this disclosure.

In one non-limiting exemplary embodiment of the present disclosure, a static mixer unit is provided. The static mixer unit may be installed in an exhaust gas system of an internal combustion engine for treating the exhaust gases before releasing it to the environment. The static mixer unit is installed within the exhaust conduit or exhaust pipe of a machine or vehicle for treating and directing the exhaust gas coming out from the exhaust manifold of the exhaust gas system. The exhaust gas is a mixture of gases such as Carbon Dioxide (CO2), Water (H2O), Nitrogen (N2), Oxygen (O2), Carbon Monoxide (CO) etc. which are released to the atmosphere. The static mixer unit is configured to receive the exhaust gas flow along an inner wall of the housing in the exhaust manifold. The static mixer unit is placed in the exhaust gas flow path which diffuses the exhaust gas and gathers the fluid particles from within the exhaust gas. Thereby the exhaust gases comprising harmful elements are reduced to non-harmful elements which are expelled to the atmosphere.
Figures 1 to 3 illustrates an exemplary embodiment of the static mixer unit (100) illustrating various views of the static mixer unit (100). The static mixer unit (100) is configured with a hub (205) which is located concentrically within the housing (201). The static mixer unit (100) is provided with an inlet opening (202) and an outlet opening (203). Exhaust gases from the exhaust manifold (not shown) enters the static mixer unit (100) through the inlet opening (202). The static mixer unit (100) is configured with a plurality of angularly twisted blades (204) to deflect exhaust gases off the plurality of angularly twisted blades (204) and exit through the outlet opening (203). The plurality of angularly twisted blades (204) are spaced apart from each other and located within the concentric space in-between the housing (201) and the hub (205). In an embodiment of the present disclosure, one end of the plurality of angularly twisted blades (204) are fixed to an inner side wall (205a) of the housing (201) and other end of the plurality of angularly twisted blades (204) are fixed to the outer rim (205b) of the hub (205). In an embodiment of the present disclosure, the plurality of angularly twisted blades (204) has an angle of inclination ranging from about 30º to about 70º with respect to a hub axis (A-A) as shown in Figure 2.
The housing (201) comprising an inner wall (201a), facilitates flow of the exhaust gases along the inner wall (201a) of the housing (201). The hub (205) configured inside the housing (201) protrudes out of the housing (201) such that part of the hub (205) is outside the housing (201) and a tray (206) is configured in the hub (205) also protrudes outside the housing (201) and towards the inlet opening (202) of the static mixer unit (100) as shown in Figure 3. The tray (206) or the protruded portion of the hub (205) is in arcuate shape or convex shape to facilitate collection platform for particulate matter formed due to reaction of the exhaust gases with the sprayed ammonia. In one embodiment, the tray (206) is provided with an inclination ranging from about 0º to about 30º with respect to axis C-C. In one embodiment, the particulate matter is the matter formed due to reaction of reducing agents such as ammonia with the exhaust gases comprising mono-nitrogen oxides (NOX) or any other reducing agent which serves the purpose.

In an embodiment of the present disclosure, the exhaust gases deflects off the plurality of angularly twisted blades (204) in a spiral motion before entering the mixing chamber (209).

In an embodiment of the present disclosure, the plurality of angularly twisted blades (204) are fixed in-between the housing (201) and the hub (205) and the angularly twisted blades makes acute angle with the hub (205) with respect to the central axis (C-C) (shown in Figure 2).
In an embodiment of the present disclosure, the plurality of angularly twisted blades (204) have an axial entry at upstream (212) of the static mixer unit (100).
In an embodiment of the present disclosure, the plurality of angularly twisted blades (204) have an angular entry at upstream (212) of the static mixer unit (100).
In an embodiment of the present disclosure, the plurality of angularly twisted blades (204) have an axial exit at upstream (212) of the static mixer unit (100).
In an embodiment of the present disclosure, the plurality of angularly twisted blades (204) have an angular exit at upstream (212) of the static mixer unit (100).
In an embodiment of the present disclosure, the plurality of angularly twisted blades (204) have an axial entry at upstream (212) of the static mixer unit (100).
In an embodiment of the present disclosure, the plurality of angularly twisted blades (204) have an angular entry at downstream (213) of the static mixer unit (100).
In an embodiment of the present disclosure, the plurality of angularly twisted blades (204) have an axial exit at downstream (213) of the static mixer unit (100).
In an embodiment of the present disclosure, the plurality of angularly twisted blades (204) have an angular exit at downstream (213) of the static mixer unit (100).
In an embodiment of the present disclosure, the plurality of angularly twisted blades (204) have an axial entry at downstream (213) of the static mixer unit (100).
Figure 4 in one non-limiting exemplary embodiment of the present disclosure. The figure illustrates a static mixer unit (100) that may be installed in an exhaust gas system (500) of an internal combustion engine. The static mixer unit (100) is placed within an exhaust pipe (207) which may be connectable to the exhaust manifold (not shown in figure). An injector unit (208) is provided at the vicinity of inlet of the exhaust pipe (207) such that, the spray fluid from the injector unit (208) is directed along the exhaust gas flow path. The spray fluid released from the injector unit (208) mixes with the exhaust gas (as shown in Figure 5) and impinges on the inner side wall (205a) of hub (205) of the static mixer unit (100). Exhaust gas from the exhaust manifold passes through the static mixer unit (100) and the exhaust gas gets deflected upon impinging with plurality of angularly twisted blades (204). The deflected exhaust gas enters a mixing chamber (209), which facilitates centrifugal mixing of the exhaust gas as well as Diesel Exhaust Fluid (DEF). The mixing chamber (209) creates homogeneity at inlet of the Selective Catalyst Reduction (SCR) chamber (210) before the treated exhaust gas is exhausted into the atmosphere.

The exhaust gas from the exhaust manifold mixes with the ammonia jet sprayed from the injector unit (208) and impinges on the inner wall (205a) of the hub (205). During impingement of the exhaust gas on the static mixer unit (100) the diesel exhaust fluid (DEF) breaks down into droplets of fluid. These fluid particles are gathered in the hub (205) and then collected in the tray (206). In an embodiment of the present disclosure, the hub (205) is open at one end and the other end of the hub (205) is closed. The exhaust gas impinging on the inner wall (205a) of the hub (205) forms fluid droplets and accumulates in the tray (206) of the static mixer unit (100). The injector unit (208) is directed to impinge directly onto the hub (205) such that, the exhaust gas mixes with the ammonia sprayed from the injector unit (208) and fluid breakdown occurs within the hub (205).

In an embodiment of the present disclosure, the exhaust gas entering the exhaust pipe (207) may comprise gases and compounds such as Carbon Dioxide (CO2), water (H2O), Nitrogen (N2), Oxygen (O2), Carbon Monoxide (CO), un-burnt Hydrocarbons (HC) etc. which are harmful to the environment. Pre-treatment of these harmful exhaust gases have to be carried out before exhausting the same into the atmosphere.

In an embodiment of the present disclosure, the exhaust gas as it flows through the exhaust pipe (207) mixes with ammonia sprayed from the injector unit (208) which leads to hydrolysis reaction.

In an embodiment of the present disclosure, the ammonia injected into the exhaust pipe (207) reacts with the exhaust gas in the Selective Catalyst Reaction (SCR) chamber (210), wherein mono-nitrogen oxides (NOX) is broken down into Nitrogen (N2), Oxygen (O2), carbon dioxide (CO2) and water vapour (H2O) thereby, reducing the harmful gases in the exhaust gases.

Advantages
In an embodiment, the harmful elements in the exhaust gas from the exhaust manifold are reduced by the impingement and fluid diffusion before exhausting into the atmosphere.
In an embodiment, the tray provided to the hub of the static mixer unit collects fluid particles from the exhaust gas mixture and directs the fluid particles through the mixing chamber of the exhaust system.
In an embodiment, the tray provided on the hub is an economical way of reducing harmful particles in the exhaust gas by fluid breakdown. This static mixer unit avoids additional components in the exhaust system for exhaust gas reduction.
In an embodiment, the tray collects the fluid particles through the fluid particle diffusion and the reduced exhaust gas [i.e. water molecules] is let out into the environment.
In an embodiment, curved tip ends of the plurality of angularly twisted blades generate spiral exhaust gas flow for mixing exhaust gases and to regulate the exhaust gas flow into the atmosphere.
REFERRAL NUMERALS
100 Static Mixer Unit
500 Exhaust gas System
201 Housing
201a Inner wall
202 Inlet opening
203 Outlet opening
204 Plurality of angularly twisted blades
204a Curved tip end
205 Hub
205a Inner side wall
206 Tray
207 Exhaust pipe
208 Injector unit
209 Mixing chamber
210 Selective Catalyst Reduction chamber
211 Fluid spray or Ammonia spray
212 Upstream
213 Downstream
A-A and C-C Hub axes

EQUIVALENTS

With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.

It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to “at least one of A, B, or C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B.”

In addition, where features or aspects of the disclosure are described in terms of Markush groups, those skilled in the art will recognize that the disclosure is also thereby described in terms of any individual member or subgroup of members of the Markush group.

While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope being indicated by the following claims.