System, method, and article of manufacture for cooling and filtering engine intake air

Various methods and systems are provided for an air induction system for an engine. In one example, the air induction system includes an intake conduit and an assembly coupled to the intake conduit which includes a water spray for removing particulates from, and for cooling, intake air flowing through the water spray.

FIELD

Embodiments of the invention relate to air intake systems for an engine. Other embodiments relate to systems, methods, and assemblies for treating ambient intake air of an engine.

BACKGROUND

Internal combustion engines may employ a filter to clean a flow of intake air before it enters the engine. In this manner, an amount of particulates that enters the engine may be reduced, thereby reducing engine degradation, for example. Further, internal combustion engines may employ a cooler, such as a charge air cooler, to cool the flow of intake air before it enters the engine, thereby increasing the density of the intake air, resulting in increased engine performance.

In some examples, a vessel that includes the engine may travel through conditions in which the air is particulate-laden with fine particulates, such as fine sand particles. In such an example, the air filter and/or charge air cooler may become clogged, resulting in reduced engine operating efficiency and reduced cooling.

BRIEF DESCRIPTION

In one embodiment, an air induction system for an engine is disclosed. The air induction system comprises an intake conduit and an assembly coupled to the intake conduit which includes a water spray for removing particulates from, and for cooling, intake air flowing through the water spray.

In such an embodiment, the water spray may be delivered by at least one conduit which traverses the assembly and includes a plurality of delivery ports such that the cross-section of the assembly is sprayed with water. As such, the water spray may contact particulates in the airflow thereby removing them from the airflow. Further, the water spray may provide cooling to the airflow if the temperature of the water in the water spray is less than the temperature of the intake air. In this manner, the assembly filters and cools intake air that passes through it.

DETAILED DESCRIPTION

The following description relates to various embodiments of an air induction system of an engine that includes a combined filter-cooler assembly for filtering and cooling the flow of intake air.FIG. 1shows an example in which the combined filter-cooler assembly is coupled to an intake conduit of an air induction system of an engine included in a marine vessel. Details of example embodiments of the combined filter-cooler assembly are described with reference toFIGS. 2 and 3. For example,FIG. 2shows a perspective view of an example embodiment of the combined filter-cooler assembly in which an upstream side of the combined filter-cooler assembly is visible.FIG. 3shows a side view of the combined filter-cooler assembly which includes a water circuit that supplies water to a water spray region of the combined filter-cooler assembly and filters water that drains from the combined filter-cooler assembly. Further details of a water delivery conduit which traverses the water spray region are described with reference to a perspective view of the conduit shown inFIG. 4. An example method for the combined filter-cooler assembly is described with reference toFIG. 5.

FIG. 1is a block diagram of an example embodiment of a system, herein depicted as a marine vessel100, such as a ship, configured to operate in a body of water101. The marine vessel100includes a propulsion system102with an engine104. However, in other examples, engine104may be a stationary engine, such as in a power-plant application, or an engine in a rail vehicle propulsion system. In the example embodiment ofFIG. 1, a propeller106is mechanically coupled to the engine104such that it is turned by the engine104. In other examples, the propulsion system102may include a generator that is driven by the engine, which in turn drives a motor that turns the propeller, for example.

The engine104receives intake air for combustion through an air induction system108which includes an intake conduit114. The intake conduit114receives ambient air from outside of the marine vessel100. Exhaust gas resulting from combustion in the engine104is supplied to an exhaust passage116. Exhaust gas flows through the exhaust passage116, and out of an exhaust stack118of the marine vessel100. In one example, the engine104is a diesel engine that combusts air and diesel fuel through compression ignition. In other non-limiting embodiments, the engine104may combust fuel including gasoline, kerosene, biodiesel, or other petroleum distillates of similar density through compression ignition (and/or spark ignition).

In the example embodiment ofFIG. 1, a turbocharger120is arranged between the intake conduit114and the exhaust passage116. The turbocharger120increases air charge of ambient air drawn into the intake conduit114in order to provide greater charge density during combustion to increase power output and/or engine-operating efficiency. The turbocharger120includes a compressor122arranged along the intake conduit114. The compressor122is at least partially driven by a turbine124(e.g., through a shaft126) that is arranged in the exhaust passage116. While in this case a single turbocharger is shown, the system may include multiple turbine and/or compressor stages. Further, the air induction system108includes a charge air cooler (CAC)146arranged in the intake conduit114downstream of the compressor122. The CAC146cools the air charge of ambient air after it passes through the turbocharger120in order to further increase the intake air charge density thereby further increasing the engine operating efficiency.

Further, the air induction system108depicted in the example embodiment ofFIG. 1includes a combined filter-cooler assembly200. The combined filter-cooler assembly200is configured to remove particulates from the ambient intake air, as well as cool the ambient intake air, via a water spray, as will be described in greater detail below with reference toFIGS. 2-5. For example, the marine vessel may travel through areas where a relatively large amount of thin, fine sand is present in the ambient intake air. Under such conditions, an air filter composed of fibrous materials, for example, may become easily clogged. In the example embodiment shown inFIG. 1, the combined filter-cooler assembly is positioned upstream of the CAC146in the intake conduit114.

The marine vessel100further includes a controller148to control various components related to the propulsion system102. In one example, the controller148includes a computer control system. The controller148further includes computer readable storage media (not shown) including code for enabling on-board monitoring and control of marine vessel operation. The controller148, while overseeing control and management of the propulsion system102, may be configured to receive signals from a variety of engine sensors150, as further elaborated herein, in order to determine operating parameters and operating conditions, and correspondingly adjust various engine actuators152to control operation of the marine vessel100. For example, the controller148may receive signals from various engine sensors150including, but not limited to, engine speed, engine load, boost pressure, exhaust pressure, ambient pressure, ambient temperature, etc. Correspondingly, the controller148may control the propulsion system102by sending commands to various components such as cylinder valves, throttle, etc.

FIGS. 2 and 3show examples of combined filter-cooler assemblies200and300, respectively, such as the combined filter-cooler assembly200shown inFIG. 1, which may be articles of manufacture. In the examples illustrated inFIGS. 1-3, like parts are identified by like reference numbers. As depicted in the schematic diagram shown inFIG. 2, the combined filter-cooler assembly200is positioned in the intake conduit114such that ambient intake air flows through the combined filter-cooler assembly200before flowing to an inlet of the compressor of the turbocharger. In this way, substantially all of the ambient intake air that enters the intake conduit114is filtered and cooled by the combined filter-cooler assembly200.

As shown in the embodiment illustrated inFIG. 2, the combined filter-cooler assembly200includes a body201that encloses a water spray region202. The body may be made of stainless steel, for example, or another suitable material that is resistant to rust. The combined filter-cooler assembly200is part of, and forms a section of, the air intake conduit114. For example, a first conduit may lead up to an ingress of the combined filter-cooler assembly, the ingress receiving air from external to the engine. A second conduit may lead away from an egress of the combined filter-cooler assembly, the egress delivering the intake air to an intake of the engine.

The perspective view of the combined filter-cooler assembly200depicted inFIG. 2shows an upstream side of the body (e.g., ingress) including a perforated screen240with a plurality of perforations242dispersed across the length and width of the perforated screen240. In some examples, the perforated screen240may be made of the same material as the rest of the body, such as stainless steel. In other examples, the perforated screen240may be made of a material that is different than the rest of the body, such as a porous material that is permeable to the flow of intake air, for example. Although the perforations242are depicted as having a round shape, it should be understood the perforations may have any suitable shape. Further, as shown inFIG. 2, each perforation242has substantially the same size. For example, each perforation may have a diameter of 1 inch (2.54 cm). In other examples, the perforations may have varying sizes.

In some embodiments, a downstream side (not shown) of the body (e.g., egress) may be substantially open such that airflow exiting the combined filter-cooler assembly is unimpeded. In other embodiments, the downstream side of the body may have a similar structure to the upstream side of the body depicted inFIG. 2. In still other embodiments, the downstream side of the body may be comprised of a number of horizontal slats traversing the width of the downstream side such that direction of the airflow exiting the combined filter-cooler assembly is returned to its initial direction.

Further, at least one turbulence-generating slat may traverse the water spray region202in a direction perpendicular to the flow direction of intake air (e.g., perpendicular to the plane of the page inFIG. 3). In the example embodiments depicted inFIGS. 2 and 3, a plurality of slats traverse the water spray region202. For example, downwardly curved slats204and upwardly curved slats206are shown dispersed throughout the water spray region202, each slat having substantially the same radius of curvature. As depicted, alternating columns of downwardly curved slats204and upwardly curved slats form an alternating inversion pattern. In the example embodiment ofFIG. 3, the curved slats are angled with respect to initial direction of the flow of intake air. For example, curved slats204have an angle indicated at205(e.g., 15°) and curved slats206have an angle indicated at207(e.g., −15°). The curved slats change the direction of the intake airflow thereby generating turbulence in the airflow as it travels through the combined filter-cooler assembly. In some examples, one or more slats may have a different radius of curvature. In other embodiments, the slats may be flat instead of curved and the slats may have different angles with respect to the initial airflow direction (e.g., 20°, 60°, etc.), for example. In still other embodiments, the combined filter-cooler assembly may include a combination of curved and flat slats. Further, in some embodiments, the slats may be dispersed in a random array throughout the water spray region202.

The curved slats204and206may be made of the same material as the body of the combined filter-cooler assembly, such as stainless steel, for example. In other examples, the curved slats may be made of a different material than the body of the combined filter-cooler assembly. Further, the curved slats204and206may be coated with polytetrafluoroethylene or nitrated with salt bath. In this manner, degradation of the blades from water contact and/or build up of particulates from the intake air may be reduced.

Further, at least one conduit, such as a water delivery conduit, may traverse the water spray region202in a direction perpendicular to the flow direction of intake air (e.g., perpendicular to the plane of the page inFIG. 3). The at least one conduit may be positioned downstream of at least one of the slats that traverses the water spray region202. The conduit may be a tube or a pipe, for example. Further, the conduit may be made of any suitable material, such as metal, plastic, or rubber. In the example ofFIG. 3, the combined filter-cooler assembly200includes a plurality of upstream conduits214(e.g., eight conduits arranged in two columns of four) fluidically coupled (not shown inFIG. 3) to an upstream water header212and a plurality of downstream conduits210(e.g., four conduits) fluidically coupled (shown inFIG. 2) to a downstream water header208. As depicted, the downstream conduits210are aligned in parallel along a vertical direction of the combined filter-cooler assembly200. Likewise, the four upstream conduits214in each of the two conduits are aligned in parallel along a vertical direction of the combined filter-cooler assembly200. Further, the upstream conduits214and downstream conduits210form four rows in which the conduits are aligned in parallel along a horizontal direction (e.g., airflow direction) in each row. In other embodiments, the alignment of the conduits may be staggered, for example. It should be understood that the combined filter-cooler assembly may include any suitable number of water headers which may supply water to any suitable number of conduits, as desired.

The number and positions of the slats and conduits traversing the combined filter-cooler assembly is such that the intake airflow path is unimpeded at a macro level. For example, the airflow path of the combined filter-cooler assembly extends from the ingress to the egress. At the macro level, the unimpeded intake airflow path may be free of any restriction smaller than 1 mm, for example. Specifically, the unimpeded intake airflow at the macro level may have all openings within the filter-cooler assembly with a height and width, or a diameter, of at least 1 mm, for example. In an embodiment, due to the unimpeded airflow at a macro level, the intake air is only filtered within the water spray region of the assembly by way of its interaction with the water spray. This allows substantially all the particulates removed from the intake air by the water to fall to the bottom of the assembly for collection and subsequent filtration of the particulates from the water. It also allows for filtration and removal of relatively large particles, such as sand, without clogging a conventional mechanical filter.

In the example embodiment depicted inFIG. 2, the fluidic coupling between the water headers and the water delivery conduits is shown. For example, downstream water header208is formed in an upside down U-shape around the combined filter-cooler assembly200, and each end of four conduits210that traverse a water spray region202is fluidically coupled to the water header208. Upstream water header212is formed in an upside down U-shape around the combined filter-cooler assembly200, and each end of eight conduits214that traverse the water spray region202is fluidically coupled to the water header212. In such a configuration, the coupling of each end of a water delivery conduit to the U-shaped water header allows for uniform pressure along the length of each of the conduits, and therefore, a uniform water pressure maybe be delivered by each of the conduits.

FIG. 4shows an example embodiment of a section of a water delivery conduit400, such as an upstream conduit214or a downstream conduit210described above with reference toFIGS. 2 and 3. As shown in the example ofFIG. 4, the conduit400includes a plurality of delivery ports that are dispersed along the length of the conduit400through which water is delivered in different directions to the water spray region of the combined filter-cooler assembly. For example, the conduit400includes delivery ports402along the length of the top of the conduit400and delivery ports404along the bottom of the conduit. The conduit400further includes delivery ports408along one side of the conduit400(e.g., the downstream side) and delivery ports410along the opposite side of the conduit400(e.g., the upstream side). As shown inFIG. 4, the delivery ports form a t-shape through a cross-section of the conduit400, as indicated by lines406and412. In this manner, water spray may be delivered along the length, width, and depth of the combined filter-cooler assembly thereby spanning a full cross-section from top to bottom of the interior of the combined filter-cooler assembly.

In other examples, the delivery ports may form an x-shape through a cross-section of the conduit. In still other examples, the delivery ports may be formed in a spiral or random array along the length of each conduit. Furthermore, one or more conduits traversing the combined filter-cooler assembly may have delivery ports positioned in a different configuration. Thus, the delivery ports may be dispersed in a desired configuration along the length, width, and depth of the combined filter-cooler assembly thereby delivering water spray to substantially the entire interior of the combined filter-cooler assembly.

Continuing withFIG. 3, the upstream water header212may be a high pressure water header that delivers a relatively high pressure water spray, and the downstream water header208may be a low pressure water header that delivers a relatively low pressure water spray. As such, the upstream water header212and upstream conduits214form a high pressure water assembly, and the downstream water header208and downstream conduits210form a low pressure water assembly. The high pressure water spray may be delivered upstream of the low pressure water spray so that the high pressure water spray may contact the particulates in the flow of intake air such that they are knocked out of (e.g., removed from) the turbulent airflow. Particulates that are removed from the airflow fall uncollected to a bottom of the assembly, as will be described in greater detail below. In this manner, the particulates are washed from the flow of intake air, for example. Some cooling of the airflow may occur as the water passes through the high pressure water spray. Once at least some of the particulates have been removed from the airflow, the airflow moves through the low pressure water spray in which it is further cooled and humidified by the spray of relatively low pressure water.

The water header208is supplied with water by water pump234which may be a high pressure water pump (e.g., water pump234supplies water with a relatively higher pressure than water pump230) that is in included in a water supply circuit of the combined filter-cooler assembly200. The water header212is supplied with water by water pump230which may be a low pressure water pump (e.g., water pump230supplies water with a relatively lower pressure than water pump234) that is included in the water supply circuit. The supplies of water from pumps234and230to the water headers208and212are controlled by valves236and232, respectively. The valves232and236may be globe valves or check valves, for example, in communication with a controller, such as controller148described with reference toFIG. 1.

The pumps230and234pump water from water supply228. In some embodiments, water supply228may be water (e.g., sea water) from the body of water in which the marine vessel in which the combined filter-cooler assembly is positioned is traveling. In other examples, the water supply228may be a make-up feed tank which holds fresh water. The water supply228may further include water which has been drained from the combined filter-cooler assembly and filtered by the water filtration circuit.

Particulates that are removed from the water spray region and fall to the bottom of the combine filter-cooler assembly, as well as at least some of the water that is delivered to the water spray region, are collected in a collector216positioned at a base of the combined filter cooler assembly200(e.g., the bottom of the combined filter-cooler assembly). As shown in the example embodiments ofFIGS. 2 and 3, collector216has a pan shape with a drain conduit218that extends the width of the collector216and is fluidically coupled to the water filtration circuit. In other embodiments, the collector216may have a funnel shape with a single hole at the bottom as a drain that is fluidically coupled to the water filtration circuit. The drain conduit218may have a length or diameter that is large enough that particulates that fall into the collector216can be drained from the collector (e.g., at least the size of perforations242in the perforated screen240). In this example, particulates impacted and/or entrain by the water spray pass down, uncollected, until the particles then can be drained and flushed out. In this way, the intake airflow path may remain unimpeded at a macro level even when particulates are continually removed over a long period of engine operation. Further, clogging of the drain conduit218and the collector216may be reduced, since this configuration avoids particulates being collected on a filter and then dripping down in such a way as may clog the system.

The water filtration circuit includes eductor220which is configured to pump water and particulates from the collector216. For example, valve238may be opened during operation of the water pump230to create a venturi effect in the eductor220which draws water and particulates from the collector216and through the eductor220. Valve238may be a globe valve or a check valve, for example, in communication with a controller, such as controller148described with reference toFIG. 1.

After passing through the eductor220, water and particulates enter a first filter224, such as a duplex strainer, where larger particulates are removed. In the example in which the first filter224is a duplex strainer, particulates collected by the duplex strainer may be removed manually as needed, for example.

After passing through the first filter224, water and any remaining particulates enter a second filter226, such as a separator or three-wing device, which removes finer particulates from the flow. In the example in which the second filter is a separator or three-wing device, the finer particulates (e.g., sand) collected by the separator or three-wing device may be discharged to the body of water in which the marine vessel is traveling. Water that has been filtered by the second filter224then passes to the water supply228. It should be understood that the components of the water filtration circuit described above are for the purpose of example, and one or more of the components of the water filtration circuit may be removed or replaced without departing from the scope of the present invention.

Continuing toFIG. 5, it shows a flow chart illustrating an example embodiment of a method500for a combined filter-cooler assembly, such as combined filter-cooler assembly200or300described above with reference toFIGS. 2 and 3, respectively. Specifically, method500describes the flow of intake air through the combined filter-cooler assembly and how it is filtered and cooled.

At510of method500, ambient intake air is inducted into the combined filter-cooler assembly. As described above with reference toFIG. 2, the combined filter-cooler assembly may include a perforated screen on the upstream side of the assembly such that relatively large particulates (e.g., larger than the size of the perforations) are filtered from the flow of intake air as the intake air enters the combined filter-cooler assembly.

At512of method500, the intake air flows over curved slats, such as slats204and206described above with reference toFIGS. 2 and 3, such that turbulence is generated in the airflow. In this manner, the direction of the airflow is changed and the particulates, which are heavier than the air, may impact the slats instead of following the change in direction of the airflow.

Once turbulence is generated in the flow of intake air, the intake flows through a high pressure water spray at514of method500. For example, a high pressure pump may be operated to deliver the water spray through delivery ports in one or more first water delivery conduits fluidically coupled to the high pressure water pump, as described above, such that the high pressure water spray spans a cross-section from top to bottom of the interior of the combined filter-cooler assembly. The high pressure water spray contacts particulates in the airflow thereby removing them from the airflow. Further, the high pressure water spray may provide some cooling to the flow of intake air.

After flowing through the high pressure water spray, the intake air flows through a relatively low pressure water spray at516of method500. For example, a low pressure pump may be operated to deliver the water spray through delivery ports in one or more low pressure water delivery conduits (one or more second water delivery conduits) fluidically coupled to the low pressure water pump, as described above, such that the low pressure water spray spans a cross-section from top to bottom of the interior of the combined filter cooler assembly. The low pressure water spray may provide greater cooling to the flow of intake air than the high pressure water spray, as well as provide some particulate removal. Additionally, by flowing the intake air through the high pressure and low pressure water sprays, the intake air may be humidified, which may assist in reducing NOxemissions, for example.

At518of method500, particulates that are removed from the water sprays, as well as some of the water from the water sprays, are collected in a collector positioned at the base of the combined filter-cooler assembly, such as collector216described above with reference toFIGS. 2 and 3.

Particulates and water that are collected in the collector, are drained to a water filtration circuit at520of method500. The water filtration circuit may include at least one filter which removes particulates from the water. The filtered water may then flow to a tank where it may be pumped to be used again in the combined filter-cooler assembly.

At522of method500, the filter and cooled flow of intake air is directed to the engine. In some examples, the airflow may be compressed by a compressor of a turbocharger and/or further cooled by a charge air cooler such that the air charge reaches a desired density, for example.

Thus, the combined filter-cooler assembly may include one or more turbulence-generating slats which traverse the assembly in a direction perpendicular to the flow direction of the intake air and one or more water delivery conduits which traverse the assembly in a direction perpendicular to the flow direction of the intake air. In this manner, the combined filter-cooler assembly may remove particulates from the flow of intake air as well as cool and humidify the flow of intake air.

Another embodiment relates to an air induction system for an engine. The air induction system includes an assembly configured to be coupled upstream of the air intake of an engine. The assembly includes a body (e.g., housing) and a water spray system attached to the body. The water spray system is configured to spray water in a water spray region in an interior of the body. In operation, intake air for the engine is drawn through the water spray region, where it encounters the water spray for removal of particulates from the intake air, and for cooling. Subsequent the water spray, the intake air is passed to the engine air intake.

In an embodiment, the water spray region, which is the entirety of the region in the body where water is sprayed, is filter-less, meaning there is no mesh (fiber) or other mechanical filter in the water spray region. Here, the intake air is only filtered within the water spray region of the assembly by way of its interaction with the water spray. This allows substantially all the particulates removed from the intake air by the water to fall to the bottom of the assembly for collection and subsequent filtration of the particulates from the water. It also allows for filtration and removal of relatively large particles, such as sand, without clogging a conventional mechanical filter.

In another embodiment, at least part of the water spray region is filter-less from a vertical perspective. That is, there is at least one sub-region of the water spray region, extending vertically from the top of the body (e.g., from spray outlet(s) of the water spray system where water is outputted into the water spray region), to the bottom of the body where water collects, where there is no mesh (fiber) or other mechanical filter through which the water would pass. Thus, in at least this sub-region, water can pass from the top of the body (e.g., spray outlets) to the bottom of the body, without encountering a mechanical filter. Such an arrangement facilitates the passage of removed particulates to the bottom of the body.

Another embodiment relates to an article of manufacture. The article includes a body (e.g., housing) having an interior. The article further includes a water spray system attached to the body. The water spray system is configured to spray water in a water spray region within the interior of the body. The body is configured for attachment to an air intake system of an engine, upstream of where intake air is drawn into the engine for combustion. The body is also configured for intake air to pass through the water spray region. The article also includes a plurality of slats traversing the water spray region in the interior of the body in a direction perpendicular to a flow direction of the intake air. In operation, the article is attached upstream of where intake air is drawn into an engine for combustion. Intake air is drawn through the water spray region, and the water spray system sprays water into the water spray region. The sprayed water removes particulates from the intake air, and cools the intake air. Interaction of the intake air and/or sprayed water with the slats creates turbulence, for helping to increase the extent to which particulates are removed.

Another embodiment relates to an article of manufacture. The article includes a body (e.g., housing) having an interior. The article further includes a water spray system attached to the body. The water spray system is configured to spray water in a water spray region within the interior of the body. The body is configured for attachment to an air intake system of an engine, upstream of where intake air is drawn into the engine for combustion. The body is also configured for intake air to pass through the water spray region. The water spray system includes a high pressure water assembly with one or more first water delivery conduits traversing the water spray region for removing particulates from intake air passing through the water spray region. The water spray system also includes a low pressure water assembly with one or more second water delivery conduits traversing the water spray region for cooling the intake air. The article also includes a plurality of turbulence-generating slats traversing the water spray region in the interior of the body in a direction perpendicular to a flow direction of the intake air.

Another embodiment relates to an air induction system for an engine. The system includes an intake conduit having an ingress and an egress, the ingress for receiving intake air from external to the engine and the egress for delivering the intake air to an intake of the engine. The system further includes an assembly coupled to the intake conduit between the ingress and egress. The assembly includes a body (e.g., housing) with an interior, and a water spray system, attached to the body, for spraying water in a water spray region in the body interior. When intake air passes through the water spray region, the sprayed water removes particulates from, and cools, the intake air flowing through the sprayed water. The body interior includes an unimpeded airflow path, at a macro level, extending from the ingress to the egress. Thus, intake air flowing through the assembly encounters only the water spray for particulate filtration. The assembly may further include a plurality of slats disposed in the water spray region, e.g., perpendicular to the flow of intake air through the water spray region, for creating air turbulence.

In an embodiment, each of the slats is a strip of metal, plastic, or other material, e.g., a relatively long and narrow strip of material. In an embodiment, each slat has a longitudinal axis defined by its longest dimension, which axis is perpendicular or about perpendicular (meaning perpendicular but for manufacturing tolerances) to the direction of intake air flow through the assembly.

As explained above, the terms “high pressure” and “low pressure” are relative, meaning that “high” pressure is a pressure higher than a “low” pressure. Conversely, a “low” pressure is a pressure lower than a “high” pressure.