Water-cooled casing treatment parts

Abstract

The present invention provides a "water-cooled casing treatment". Provides a method and system for preventing compressor surge while improving compressor efficiency and performance. In one example, the method may include cooling a recirculation passage in a compressor equipped with a casing treatment.

Description

Technical Field

[0001] The present description generally relates to methods and systems for controlling a vehicle engine to reduce compressor surge and improve compressor efficiency. Background Art

[0002] Supercharged engines have become increasingly popular due to the improved fuel economy and power output obtained by incorporating turbochargers into engine systems. A turbocharger includes a compressor coupled to a turbine via a drive shaft. The turbine is typically exhaust-driven, so boost is supplied to the combustion chamber of the engine system by utilizing energy generated by the engine that would otherwise be released as waste by the engine. The rotation of the turbine forces the compressor, which is fluidly coupled to an intake manifold in the engine, to rotate, thereby delivering boosted air to the engine. The use of a compressor can allow a smaller displacement engine to provide as much power as a larger displacement engine, but with additional fuel economy benefits.

[0003] However, compressors are susceptible to surge. For example, when the operator quickly releases the accelerator pedal, the air flow into the compressor inlet is reduced, resulting in a reduction in forward flow through the compressor while the compressor is still at a high pressure ratio (PR). This can cause pressure to build up at the outlet end of the compressor, driving the air flow in reverse, which can degrade components of the compressor. As another example, compressor surge can occur during high levels of cooled exhaust gas recirculation (EGR), increasing compressor pressure while reducing mass flow through the compressor.

[0004] Various methods have been developed to address the problem of compressor surge. Sun et al. show an exemplary approach in US2001 / 0173975 A1. A turbocharger with an active sleeve treatment is disclosed therein. The active sleeve treatment includes a bleed port and an injection port in a sleeve arranged in the compressor intake duct. The recirculation passage surrounds the sleeve and is fluidly connected to the bleed port adjacent to the impeller of the compressor at a first end. The second end of the recirculation passage is fluidly connected to the intake passage of the compressor through the recirculation port. During low mass flow conditions where pressure accumulates downstream of the impeller front blade, air can flow out of the impeller area, pass through the bleed port and the recirculation passage in the opposite direction to the flow through the intake passage, to enter the intake passage via the recirculation port. The additional air flow entering the intake passage can allow the compressor to operate at a lower airflow before surge occurs.

[0005] Gu et al. show another exemplary approach to reduce the occurrence of compressor surge in US8,061,974 B2. Among them, the compressor is adapted with a cover with ports of variable geometry and a bypass channel. The cover is adjusted so that the port in the cover alternates between a first warp position and a second warp position. When the port is arranged in the first warp position, air is recirculated in the upstream direction from the downstream end of the bypass channel to return the air to the intake channel of the compressor. This positioning of the port guides additional airflow to the intake channel, thereby alleviating the pressure accumulation at the compressor outlet end and reducing the possibility of surge. When the port is adjusted to the second warp position, air flows in the forward direction through the bypass channel to the impeller, thereby avoiding compressor blockage.

[0006] However, the inventors herein have recognized potential problems with such systems. As one example, the recirculation flow circulates heated air through the compressor intake due to compression. This can reduce the density of the charge air delivered to the engine combustion chamber, thereby reducing the boost potential of the air and reducing engine efficiency. In another example, the adaptation of a variable geometry ported cover tends to include a complex control system, which results in a more expensive production cost. Summary of the invention

[0007] In one example, the above problem can be solved by a method for flowing intake air through a compressor intake passage to an impeller and recirculating a portion of the intake air from the impeller back to an inlet to the compressor intake passage via a set of guide vanes positioned in a recirculation passage circumferentially surrounding the compressor intake passage. The intake air can be cooled in the recirculation passage via a cooling jacket circumferentially surrounding the recirculation passage. In this way, compressor surge can be mitigated while improving compressor efficiency and engine performance, while maintaining a fixed geometry to avoid increasing control complexity and manufacturing costs.

[0008] As an example, air recirculated through the compressor inlet may be cooled by a cooling jacket surrounding a recirculation passage. A coolant circulates through the cooling jacket, thereby extracting heat from the heated air through cooling surfaces of the recirculation passage. To maximize the cooling effect of the cooling jacket, structures may be arranged in the recirculation passage to direct and prolong contact between the recirculation air and the cooling surfaces.

[0009] In this way, compressor surge can be mitigated by extending the lower limit of the low mass flow range to allow the compressor to operate stably. In addition, engine performance can be improved by increasing the density of the recirculated air, which increases the boost potential of the air delivered to the engine combustion chamber and also improves the fuel economy of the vehicle. The technical effect of cooling the recirculation passage and configuring the recirculation passage with a structure that guides the airflow is to achieve an extension of the surge limit while improving the compressor efficiency.

[0010] It should be understood that the above summary is provided to introduce a series of concepts in a simplified form, which are further described in the detailed description. This is not meant to identify key or essential features of the claimed subject matter, the scope of which is uniquely defined by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that address any disadvantages noted above or in any part of this disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 An exemplary engine system for a hybrid vehicle is shown.

[0012] Figure 2 An exemplary compressor map is shown.

[0013] Figure 3 A cross-sectional view of a compressor adapted with a recirculation passage is shown.

[0014] Figure 4A is a front view of a first embodiment of a set of guide vanes for a recirculation passage.

[0015] Figure 4B is a front view of a second embodiment of a set of guide vanes for a recirculation passage.

[0016] Figure 4C is a front view of a third embodiment of a set of guide vanes for a recirculation passage.

[0017] Figure 5 is an isometric perspective view of the guide vanes.

[0018] Figure 6 is a schematic diagram showing a cooling circuit coupled to a turbocharger.

[0019] Figure 7 is a first cross-sectional view of an embodiment of a guide structure for a cooling jacket.

[0020] Figures 3 to 4C and Figure 7 Drawn approximately to scale. DETAILED DESCRIPTION

[0021] The following description relates to systems and methods for reducing the occurrence of compressor surge by cooling airflow through a recirculation passage at a compressor inlet. Figure 1 A non-limiting embodiment of a hybrid vehicle system including a turbocharged engine is shown in FIG. Figure 2 An exemplary compressor characteristic line diagram is provided in , which depicts the pressure ratio as a function of air flow rate to surge limit. A turbocharged engine may utilize an exhaust turbine to drive a compressor, which may be positioned in an intake passage of the engine. The compressor may include an outer casing having an inlet duct (e.g., an intake passage) surrounding a casing and an impeller (e.g., a compressor wheel) disposed at a downstream end of the casing, such as Figure 3 As shown. The recirculation passage may surround the sleeve and be fluidly coupled to the intake passage through the bleed port. A set of guide vanes may be arranged in the recirculation passage, surrounding the sleeve and including angled guide vanes to guide the airflow. FIG. 4A to FIG. 4C A first embodiment, a second embodiment and a third embodiment of the set of guide vanes are shown in front views showing different alignments of the guide vanes relative to the direction of rotation of the impeller. Figure 5 The geometry of one guide vane of the set of guide vanes is depicted in FIG. The wall of the recirculation channel can be cooled by means of a cooling jacket provided in the compressor and connected to the outer casing of the cooling circuit. Figure 6 A schematic diagram of the cooling circuit is shown in FIG. Figure 7 A cross-sectional view of an embodiment of a cooling jacket adapted with internal ribs is shown in In this way, a recirculation passage that cools and directs the recirculated airflow during low mass flow conditions can reduce compressor surge and improve compressor efficiency.

[0022] Now turn to Figure 1 , shows an example of a cylinder 14 of an internal combustion engine 10 that may be included in a vehicle 5. The engine 10 may be controlled at least in part by a control system including a controller 12 and input from a vehicle operator 130 via an input device 132. In this example, the input device 132 includes an accelerator pedal and a pedal position sensor 134 for generating a proportional pedal position signal PP. The cylinder (also referred to herein as a "combustion chamber") 14 of the engine 10 may include combustion chamber walls 136 with a piston 138 positioned therein. The piston 138 may be coupled to a crankshaft 140 such that reciprocating motion of the piston is converted into rotational motion of the crankshaft. The crankshaft 140 may be coupled to at least one drive wheel 55 of the passenger vehicle via a transmission 54, as further described below. In addition, a starter motor (not shown) may be coupled to the crankshaft 140 via a flywheel to enable a starting operation of the engine 10.

[0023] In some examples, the vehicle 5 may be a hybrid vehicle with multiple torque sources available to one or more wheels 55. In other examples, the vehicle 5 is a conventional vehicle with only an engine. In the example shown, the vehicle 5 includes an engine 10 and an electric machine 52. The electric machine 52 may be a motor or a motor / generator. When one or more clutches 56 are engaged, the crankshaft 140 of the engine 10 and the electric machine 52 are connected to the wheels 55 via a transmission 54. In the depicted example, the first clutch 56 is disposed between the crankshaft 140 and the electric machine 52, and the second clutch 56 is disposed between the electric machine 52 and the transmission 54. The controller 12 may send a signal to the actuator of each clutch 56 to engage or disengage the clutch so as to connect or disconnect the crankshaft 140 with the electric machine 52 and the components connected thereto, and / or to connect or disconnect the electric machine 52 with the transmission 54 and the components connected thereto. The transmission 54 may be a gearbox, a planetary gear system, or other types of transmissions. The powertrain may be configured in various ways, including as a parallel, series, or series-parallel hybrid vehicle.

[0024] The electric machine 52 receives power from the traction battery 58 to provide torque to the wheels 55. The electric machine 52 may also operate as a generator to provide power to charge the battery 58, such as during braking operations.

[0025] Cylinder 14 of engine 10 may receive intake air via a series of intake passages 142, 144, and 146. Intake passage 146 may communicate with other cylinders of engine 10 in addition to cylinder 14. In some examples, one or more of the intake passages may include a boosting device, such as a turbocharger or a supercharger. For example, Figure 1 Engine 10 is shown configured with a turbocharger 175 including a compressor 174 arranged between intake passages 142 and 144, and an exhaust turbine 176 arranged along exhaust passage 148. When the boosting device is configured as turbocharger 175, compressor 174 may be at least partially powered by exhaust turbine 176 via shaft 180. However, in other examples, such as when engine 10 is provided with a supercharger, compressor 174 may be powered by mechanical input from a motor or the engine, and exhaust turbine 176 may optionally be omitted.

[0026] A throttle 162 including a throttle plate 164 may be disposed in the engine intake passage to vary the flow rate and / or pressure of intake air provided to the engine cylinders. For example, throttle 162 may be positioned downstream of compressor 174, such as Figure 1 as shown; or alternatively, may be disposed upstream of compressor 174.

[0027] Exhaust passage 148 may receive exhaust gas from other cylinders of engine 10 in addition to cylinder 14. Exhaust gas sensor 128 is shown coupled to exhaust passage 148 upstream of emission control device 178. Exhaust gas sensor 128 may be selected from a variety of sensors suitable for providing an indication of exhaust air / fuel ratio (AFR), such as, for example, a linear oxygen sensor or UEGO (universal or wide-range exhaust gas oxygen sensor), a two-state exhaust gas oxygen sensor or EGO (as depicted), a HEGO (heated EGO), nitrogen oxides (NOx), hydrocarbons (HC), or carbon oxides (CO) sensors. Emission control device 178 may be a three-way catalyst, a NOx trap, various other emission control devices, or combinations thereof.

[0028] Each cylinder of engine 10 may include one or more intake valves and one or more exhaust valves. For example, cylinder 14 is shown as including at least one intake poppet valve 150 and at least one exhaust poppet valve 156 located at an upper region of cylinder 14. In some examples, each cylinder of engine 10 including cylinder 14 may include at least two intake poppet valves and at least two exhaust poppet valves located at an upper region of the cylinder. Intake valve 150 may be controlled by controller 12 via actuator 152. Similarly, exhaust valve 156 may be controlled by controller 12 via actuator 154. The positions of intake valve 150 and exhaust valve 156 may be determined by corresponding valve position sensors (not shown).

[0029] In some cases, controller 12 may vary the signals provided to actuators 152 and 154 to control the opening and closing of the corresponding intake and exhaust valves. The valve actuators may be electric valve actuation type, cam actuation type, or a combination thereof. The intake valve timing and exhaust valve timing may be controlled simultaneously, or any possibility of variable intake cam timing, variable exhaust cam timing, dual variable cam timing, or fixed cam timing may be used. Each cam actuation system may include one or more cams, and may utilize one or more of cam profile switching (CPS), variable cam timing (VCT), variable valve timing (VVT), and / or variable valve lift (VVL) systems that may be operated by controller 12 to change valve operation. For example, cylinder 14 may alternatively include an intake valve controlled via electric valve actuation and an exhaust valve controlled via cam actuation (including CPS and / or VCT). In other examples, the intake and exhaust valves may be controlled by a common valve actuator (or actuation system) or a variable valve timing actuator (or actuation system).

[0030] Cylinder 14 may have a compression ratio, which is the ratio of volume when piston 138 is at bottom dead center (BDC) to volume when piston 138 is at top dead center (TDC). In one example, the compression ratio is in the range of 9:1 to 10:1. However, in some examples where different fuels are used, the compression ratio may be increased. For example, this may occur when using a higher octane fuel or a fuel with a higher latent enthalpy of vaporization. If direct injection is used, the compression ratio may also be increased due to the effect of direct injection on engine knock.

[0031] In some examples, each cylinder of engine 10 may include a spark plug 192 for initiating combustion. In a selected operating mode, ignition system 190 may provide an ignition spark to combustion chamber 14 via spark plug 192 in response to a spark advance signal SA from controller 12. The timing of signal SA may be adjusted based on engine operating conditions and driver torque demand. For example, a spark may be provided at maximum brake torque (MBT) timing to maximize engine power and efficiency. Controller 12 may input engine operating conditions (including engine speed, engine load, and exhaust AFR) into a lookup table and output the corresponding MBT timing for the input engine operating conditions. In other examples, combustion may be initiated via compression injection of fuel (e.g., as in a diesel engine).

[0032] In some examples, each cylinder of engine 10 may be configured with one or more fuel injectors for providing fuel thereto. As a non-limiting example, cylinder 14 is shown as including fuel injector 166. Fuel injector 166 may be configured to deliver fuel received from fuel system 8. Fuel system 8 may include one or more fuel tanks, fuel pumps, and fuel rails. Fuel injector 166 is shown as being directly coupled to cylinder 14 for injecting fuel directly therein in proportion to the pulse width of signal FPW-1 received from controller 12 via electronic driver 168. In this manner, fuel injector 166 provides what is known as direct injection of fuel into cylinder 14 (also referred to hereinafter as "DI"). Although Figure 1 Fuel injector 166 is shown positioned on one side of cylinder 14, but may alternatively be located on top of the piston, such as near spark plug 192. Such a location may enhance mixing and combustion when the engine is operated on alcohol-based fuels due to the lower volatility of some alcohol-based fuels. Alternatively, the injector may be located on top of and near the intake valve to enhance mixing. Fuel may be delivered to fuel injector 166 from a fuel tank of fuel system 8 via a high pressure fuel pump and a fuel rail. Additionally, the fuel tank may have a pressure sensor that provides a signal to controller 12.

[0033] Fuel injector 170 is shown arranged in intake passage 146 rather than in cylinder 14 in a configuration that provides what is known as port injection (hereinafter “PFI”) of fuel into the intake port upstream of cylinder 14. Fuel injector 170 may inject fuel received from fuel system 8 in proportion to the pulse width of signal FPW-2 received from controller 12 via electronic driver 171. It should be noted that a single driver 168 or 171 may be used for both fuel injection systems, or multiple drivers may be used, for example, driver 168 for fuel injector 166 and driver 171 for fuel injector 170, as depicted.

[0034] In an alternative example, each of fuel injectors 166 and 170 may be configured as a direct fuel injector for injecting fuel directly into cylinder 14. In yet another example, each of fuel injectors 166 and 170 may be configured as a port fuel injector for injecting fuel upstream of intake valve 150. In still other examples, cylinder 14 may include only a single fuel injector that is configured to receive different fuels in different relative amounts from a fuel system as a fuel mixture and is further configured to inject this fuel mixture directly into the cylinder like a direct fuel injector or to inject this fuel mixture upstream of the intake valve like a port fuel injector.

[0035] During a single cycle of the cylinder, fuel may be delivered to the cylinder by two injectors. For example, each injector may deliver a portion of the total fuel injection that is burned in cylinder 14. In addition, the distribution and / or relative amount of fuel delivered from each injector may vary with operating conditions (such as engine load, knock, and exhaust temperature), such as described herein below. Port-injected fuel may be delivered during an open intake valve event, a closed intake valve event (e.g., substantially before the intake stroke), and during both open and closed intake valve operations. Similarly, direct-injected fuel may be delivered, for example, during the intake stroke, and partially during the previous exhaust stroke, during the intake stroke, and partially during the compression stroke. In this way, even for a single combustion event, the injected fuel may be injected from the port injector and the direct injector at different timings. In addition, for a single combustion event, multiple injections of the delivered fuel may be performed per cycle. Multiple injections may be performed during the compression stroke, the intake stroke, or any suitable combination thereof.

[0036] Fuel injectors 166 and 170 may have different characteristics. These characteristics include size differences, for example, one injector may have a larger spray hole than the other. Other differences include, but are not limited to: different spray angles, different operating temperatures, different targeting, different injection timing, different spray characteristics, different locations, etc. In addition, depending on the distribution ratio of the injected fuel between injectors 170 and 166, different effects may be obtained.

[0037] The fuel tank in the fuel system 8 can accommodate fuels of different fuel types, such as fuels with different fuel qualities and different fuel compositions. The differences may include different alcohol contents, different water contents, different octane numbers, different heats of evaporation, different fuel mixtures, and / or combinations thereof, etc. An example of a fuel with different heats of evaporation may include gasoline with a lower heat of evaporation as a first fuel type and ethanol with a greater heat of evaporation as a second fuel type. In another example, the engine may use gasoline as the first fuel type and use an alcohol-containing fuel mixture (such as E85 (which is about 85% ethanol and 15% gasoline) or M85 (which is about 85% methanol and 15% gasoline)) as the second fuel type. Other available substances include water, methanol, a mixture of ethanol and water, a mixture of water and methanol, an ethanol mixture, etc.

[0038] The controller 12 Figure 11 is shown as a microcomputer, which includes: a microprocessor unit 106, an input / output port 108, an electronic storage medium for executable programs (e.g., executable instructions) and calibration values ​​(in this specific example, shown as a non-transitory read-only memory chip 110), a random access memory 112, a keep alive memory 114, and a data bus. Controller 12 may receive various signals from sensors coupled to engine 10, including the signals previously discussed, and in addition including: a measurement of inlet mass air flow (MAF) from mass air flow sensor 122; engine coolant temperature (ECT) from temperature sensor 116 coupled to cooling sleeve 118; exhaust temperature from temperature sensor 158 coupled to exhaust passage 148; a profile ignition pickup signal (PIP) from Hall effect sensor 120 (or other type of sensor) coupled to crankshaft 140; throttle position (TP) from throttle position sensor; signal EGO from exhaust gas sensor 128, which may be used by controller 12 to determine exhaust gas AFR; and an absolute manifold pressure signal (MAP) from MAP sensor 124. Engine speed signal RPM may be generated by controller 12 based on signal PIP. Manifold pressure signal MAP from MAP sensor 124 may be used to provide an indication of vacuum, or pressure, in the intake manifold. Controller 12 may infer engine temperature based on the engine coolant temperature and infer the temperature of catalyst 178 based on signals received from temperature sensor 158. Controller 12 may infer engine temperature based on the engine coolant temperature and the temperature of catalyst 178 based on signals received from temperature sensor 158. Figure 1 The various sensors receive signals and take actions based on the received signals and the instructions stored in the memory of the controller. Figure 1 A variety of actuators are used to adjust engine operation.

[0039] As mentioned above, Figure 1 Only one cylinder of a multi-cylinder engine is shown. As such, each cylinder may similarly include its own set of intake / exhaust valves, one or more fuel injectors, spark plugs, etc. It should be appreciated that engine 10 may include any suitable number of cylinders, including 2, 3, 4, 5, 6, 8, 10, 12, or more cylinders. Furthermore, each of these cylinders may include Figure 1 Some or all of the various components described and depicted with reference to cylinder 14 .

[0040] Due to the operating limits of the compressor, turbocharged vehicles such as Figure 1Vehicles 5) may experience problems associated with low mass flow through the turbocharger compressor. Low load compressor operator limitations will be mentioned throughout the following detailed description and may be combined with Figure 2 The compressor characteristic line diagram 200 is shown to illustrate, Figure 2 The flow rate through the compressor is shown as a function of the pressure ratio across the compressor. The surge limit depicts the lower limit of air flow for compressor operation. For example, the dashed line 202 represents the lower boundary of the surge limit. Compressor surge can occur during low compressor flow conditions (such as rapid engine unloading events) during which the turbine continues to spin at a relatively high speed, thereby pressurizing the air downstream of the compressor. This results in a high pressure area at the outlet of the compressor, driving the reversal of airflow direction, which can cause turbocharger degradation. The compressor operating efficiency - as depicted by the curve marked with percentages - decreases when the operating point approaches the surge limit. Operating in the area to the left of the dashed line 202 (e.g., at relatively low compressor mass flow and medium and high pressure ratios) can result in compressor surge and even lower efficiency. Shifting the surge line to the left can increase the compressor operating efficiency for a given operating point.

[0041] The area of ​​stable compressor operation can be obtained by configuring the compressor inlet with Figure 3 The elements depicted in and described in further detail below extend to Figure 2 The left side of the surge limit shown in the compressor characteristic line diagram 200. Among them, the cross section 300 of the compressor 302 (which can be Figure 1 174 ) shows an inlet duct 304 of a compressor 302 having a central axis 306. The central axis 306 may also be the central axis of rotation of the impeller 308. A set of reference axes 301 are provided for comparison between the views shown, indicating the "y" vertical direction, the "x" horizontal direction, and the "z" lateral direction. The direction of airflow through the inlet duct is indicated by arrow 310. The direction of flow can be a reference for the positioning of elements relative to each other. Elements relative to a reference point in the airflow path are considered to be downstream of the reference point, and elements before the reference point in the airflow path are considered to be upstream of the reference point. For example, the impeller 308 is located upstream of the diffuser 312, and the diffuser 312 is located downstream of the impeller 308.

[0042] The inlet duct 304 may include an outer casing 314 and a sleeve 316 centered on the central axis 306. The sleeve 316 may have an annular cross-section taken in a direction perpendicular to the central axis 306 and be spaced apart from an inner surface 315 of the outer casing 314. An inlet passage 318 is formed by a passage within the sleeve 316, extending along the central axis 306 from an upstream end of the inlet duct 304 to the impeller 308, positioned at a downstream end of the sleeve 316.

[0043] The impeller 308 may have a plurality of impeller blades 320 and may be connected to a turbine (such as a turbine) via a shaft 322 that drives the impeller 308 to rotate. Figure 1 The outlet end of the compressor 302 may be defined as the element of the compressor 302 that is positioned downstream of the leading edge 324 of the impeller 308. Air drawn into the compressor 302 by the rotation of the impeller 308 is decelerated through the diffuser 312 and gathered in the volute 326. Deceleration of the airflow may also occur in the volute 326 and cause an increase in pressure in the volute 326, thereby causing the gas to flow to the intake manifold of the engine.

[0044] The space between the sleeve 316 and the inner surface 315 of the outer shell 314 of the inlet duct 304 may define a recirculation passage 328 that circumferentially surrounds the sleeve 316 and extends from the upstream end of the inlet duct 304 to the downstream end. Figure 3 306, is shown as having a narrower width, defined in a direction perpendicular to the central axis 306, at an end located proximate to the impeller 308 and adjacent to the volute 326. However, in other examples of the compressor 302, the recirculation passage 328 may have a constant width across the entire length of the recirculation passage 328, as measured along the central axis 306. The recirculation passage 328 may be fluidly coupled to the intake passage 318 through a sleeve treatment that includes a bleed port 330. The bleed port 330 is an opening in the downstream end of the sleeve 316, adjacent to the impeller 308 and located downstream of the leading edge 324.

[0045] As detailed above, during conditions when compressor surge may occur (such as during low mass flow conditions), the bleed port 330 may enable a portion of the air traveling through the intake passage 318 to flow from the impeller 308 (which may also be a high pressure area) to the intake passage 318 via the bleed port 330 and the recirculation passage 328. The direction of flow through the recirculation passage 328 is shown by arrow 332 and is opposite to the direction of flow through the inlet duct 304 as indicated by arrow 310. The higher pressure in the area downstream of the leading edge 324 of the impeller 308 drives flow through the bleed port, thereby alleviating the pressure gradient across the compressor 302 and returning air to the intake passage 318 to flow again to the impeller 308. As a result, the air flow rate that strikes the leading edge 324 of the impeller 308 may be greater than the recirculated air that had not been bleed by the bleed port 330. The additional air flow may enable the compressor 302 to operate at a lower mass flow through the intake duct 304 before surge occurs.

[0046] The recirculation of air through the recirculation passage 328 of the compressor 302 prevents the compressor from operating near or past Figure 2However, the air returning to the intake passage 318 may be at least partially compressed by the impeller 308, resulting in a relative increase in the surge limit 202 relative to the air returning from the intake passage (such as Figure 1 The air in the compressor is drawn into the intake passage 142 of the compressor, heating the air. The heating results in lower density air being delivered to the intake manifold of the engine, which reduces the boost potential and therefore reduces the power output and fuel efficiency of the engine. Even cooling by a charge air cooler, which is typically arranged in the air flow path between the compressor 302 and the engine to increase the air density, may not be sufficient to compensate for the air heating caused by compression.

[0047] To address this issue, the wall of the recirculation passage 328 (which is also the inner surface 315 of the outer shell 314) can be adapted with a cooling jacket 334. The cooling jacket 334 can be a sleeve disposed within the outer shell 314, which also surrounds the recirculation passage 328. A coolant (such as water or an aqueous solution) can flow through the cooling jacket 334 via an inlet 336 and an outlet 338 in the direction indicated by arrows 340. The flow of coolant through the cooling jacket 334 can extract heat from the inner surface 315 of the outer shell 314 by convection. The cooled inner surface 315 of the outer shell 314 in turn draws heat away from the heated air flowing through the recirculation passage 328 that is in contact with the inner surface 315 of the outer shell 314. The temperature of the air flowing through the recirculation passage 328 that contacts the inner surface 315 is reduced before returning to the intake passage 318. This will be discussed below. Figure 6 and Figure 7 Details of the cooling loop that drives coolant flow through the cooling jacket 334 and the structure of the cooling jacket 334 are provided in the description of FIG.

[0048] However, if the air flow through the recirculation passage 328 is linear and coaxial with the central axis 306, a portion of the air may travel through the recirculation passage 328 without contacting the inner surface 315 of the outer casing 314 of the compressor 302. For example, 20% of the mass of the air directed through the recirculation passage 328 may directly contact the inner surface 315, while 80% of the mass of the air travels along a path through the central region of the recirculation passage 328 or along the outer surface 342 of the sleeve 316. In other examples, depending on the size of the recirculation passage 328, such as the width of the recirculation passage 328 defined in a direction perpendicular to the central axis 306, the cooled air may include 10%, 30%, or 50% of the total mass of the air. In order to increase the contact between the air in the recirculation passage 328 and the inner surface 315 of the outer casing 314, a set of guide vanes 344 may be arranged in the recirculation passage 328.

[0049] The set of guide vanes 344 may be arranged in a ring around the sleeve 316 in the flow path through the recirculation passage 328. The positioning of the set of guide vanes 344 may interrupt the linear air flow, thereby generating turbulence that causes the air to swirl radially in a horizontal direction, such as perpendicular to the central axis 306, so that a greater portion of the air mass passing through the recirculation passage 328 contacts the inner surface 315 of the outer shell 314. FIG. 4A to FIG. 4C The configuration of the set of guide blades 344 is detailed in the description of FIG.

[0050] The embodiment of the set of guide vanes 344 is FIG. 4A to FIG. 4C It is shown in FIG. 4A to FIG. 4C It is formed along the vertical and horizontal directions and by Figure 3 The dashed line AA' indicates a plane through which the cross section is taken. Elements identical to previous figures are similarly numbered. Figure 4A A first embodiment of a set of guide vanes 344a is shown. Figure 4A In the embodiment, the first guide vane 402 of the set of guide vanes 344a may be disposed across the width 404 of the recirculation passage 328 on the inner surface 315 (reference Figure 3 ) and the outer surface 342 of the sleeve 316. The other guide vanes of the set of guide vanes 344a are identical to the first guide vane 402, and the aspects described for the first guide vane 402 can be similarly applied to the other guide vanes in the set of guide vanes 344a. The first guide vane 402 has a wide end 406 in contact with the inner surface 315 of the outer shell 314 and a wedge-shaped end 408 in contact with the outer surface 342 of the sleeve 316, as well as a first curved wall 410 and a second curved wall 411. The first guide vane 402 can be angled in the recirculation passage 328 so that the first guide vane 402 is bent in a clockwise direction from the wedge-shaped end 408 to the wide end 406 and outwardly away from the central axis 306.

[0051] exist Figure 5306 , including a depth 502 of the first guide vane 402 aligned with the central axis 306. In one example, the depth 502 of the first guide vane 402 may extend from the upstream end of the sleeve 316 to a point along the length of the sleeve 316 or along a width of the cooling jacket 334 defined along the central axis 306 before the recirculation passage 328 narrows. In examples where the width of the recirculation passage 328 is constant along the entire length of the recirculation passage 328, the depth 502 may extend from the upstream end of the sleeve 316 to the upstream edge of the bleed port 330. Alternatively, the depth 502 of the first guide vane 402 may extend 50% or 75% of a portion thereof between the upstream end of the sleeve 316 and the upstream edge of the bleed port 330. As such, it should be understood that the scope of the present disclosure should not be limited by the extension of the depth 502 of the first guide vane 402 along the length of the sleeve 316 as described herein.

[0052] The set of guide vanes 344 can divide the recirculation passage 328 into individual chambers separated by each guide vane in the set of guide vanes by positioning the set of guide vanes such that the depth of each guide vane extends along the length of the sleeve 316 and along the length of the recirculation passage 328. For example, Figure 4A The chamber 412 in the recirculation passage 328 of the sleeve 316 may be defined by the outer surface 342 of the sleeve 316, the inner surface 315 of the outer casing 314, the second curved wall 411 of the first guide vane 402, and the first curved wall 413 of the second guide vane 414. The volume within the recirculation chamber 328 may thus be divided into chambers (such as chamber 412), breaking the laminar flow so that the air swirls in a radial direction that is the same as the direction of rotation of the impeller 308 (e.g., the direction of rotation of the impeller blades 320), where the direction of rotation of the impeller is indicated by arrow 416.

[0053] For example, the air flowing through the chamber 412 forms a vortex 415, which is generated due to the friction generated by contact with the curved surface. The vortex 415 causes mixing in the chamber 412, so that the air flowing through the central area of ​​the chamber 412 during the recirculation chamber 328 deviates from the linear flow, is coaxial with the central axis 306, and contacts the inner surface 315 of the outer shell 314. By dividing the inner volume of the recirculation passage 328 into individual chambers, the surface area to volume ratio in each chamber is increased, so that the airflow experiences greater turbulence. The turbulence generated by the arrangement of the set of guide vanes can force an increased contact between the air flowing through the recirculation passage 328 and the inner surface 315 of the outer shell 314 cooled by the cooling jacket 334.

[0054] exist Figure 4B and Figure 4C An alternative orientation of the set of guide vanes 344 is shown in FIG. Figure 4B In the second embodiment of the set of guide blades 344b, the third guide blade 418 may be Figure 4A The third guide blade 418 may be angled opposite to the first guide blade 402. The shape of the third guide blade 418 may be similar to the first guide blade 402, but the third guide may be curved in a counterclockwise direction from the wedge-shaped end 420 to the wide end 422 and outward from the central axis 306. Due to friction between the airflow and the curved surface of the set of guide blades 344b, the air flowing through the chamber 417 of the set of guide blades 344b may swirl in a direction opposite to the direction of rotation of the impeller (indicated by arrow 416). A vortex 419 may be generated, causing a deviation from the linear flow through the chamber 417. Therefore, the air is cooled by increasing the contact with the inner surface 315 of the outer casing 314 in which the cooling jacket 334 is disposed.

[0055] In the third embodiment of the set of guide blades 344c, each guide blade may be rectangular, such as Figure 4C As shown. The fourth guide vane 424 may have a straight edge 426 extending from the outer surface 342 of the sleeve 316 to the inner surface 315 of the outer shell 314. The width of the fourth guide vane 424 as measured in the horizontal direction is equal to the width of the second end 430 of the fourth guide vane 424 at the first end 428. The shape of the fourth guide vane 424 may not contribute to the generation of vortices in the airflow passing through the recirculation passage 328. However, the friction between the air and the straight edge 426 of the fourth guide vane 424 may generate turbulent vortices in the laminar flow, which prolongs the contact between the inner surface 315 of the outer shell 314 and the air flowing through.

[0056] By swirling the air in a first direction (eg, the same direction as the impeller 308 rotates), the vortex 415 may be directed along Figure 4A The second curved wall 411 of each guide blade in the set of guide blades 444 is formed. Figure 4B The swirl in the second direction induced by the orientation of the set of guide vanes 344 may generate a vortex 419 along the first curved wall 421 of each guide vane in the set of guide vanes 344 . Figure 4B The eddy current 419 can be used with Figure 4A The vortex 415 rotates in opposite directions. Figure 4C The straight edges of the set of guide vanes 344 may generate vortices 423 on either side of each guide vane in the set of guide vanes 344. Thus, the turbulence generated when air flows through the recirculation passage 328 may be varied by the orientation of the set of guide vanes 344.

[0057] although FIG. 4A to FIG. 4CEach of the embodiments of the set of guide vanes shown in the drawings is depicted as having eight guide vanes, but other arrangements of the set of guide vanes 344 may also be effective in enhancing the cooling of the air flowing through the recirculation passage 328. As an example, a set of guide vanes may have 6 to 15 guide vanes, depending on the size of the recirculation passage 328. In another example, the guide vanes in a set of guide vanes may have a different shape, curvature, or thickness than the examples shown in the present disclosure.

[0058] FIG. 4A to FIG. 4C The embodiment of a set of guide vanes shown in FIG. 3 can be used to increase cooling of the partially compressed air flowing through the recirculation passage 328 by interrupting the linear airflow and slowing down the flow rate. As a result, the heated air is contained within the recirculation passage for a longer period of time, thereby achieving increased heat transfer from the air to the cooler inner surface 315 of the outer shell 314. To provide continuous cooling, a cooling jacket 334 disposed in the outer shell 314 can be coupled to the cooling loop 602, as shown in FIG. Figure 6 As shown in schematic diagram 600 of .

[0059] Figure 6 The cooling loop 602 shown in FIG. 6 may include a cooling jacket 334, a heat exchanger 604 that extracts heat from a coolant (such as water) flowing through the cooling loop 602, and a pump 606 that drives the coolant flow. The direction of coolant flow through the cooling loop 602 is indicated by arrow 614. The cooling jacket 334 may extend along the inlet end of the compressor 174, which is coupled to the compressor 174 via the shaft 180. Figure 1 176 of turbocharger 175. Fresh air is drawn into intake passage 142, compressed by compressor 174, and then flows through charge air cooler (CAC) 608 via charge air passage 610. The pressurized, cooled air is then delivered to cylinder 14 via charge air passage 612 connected to intake valve 150. Exhaust generated at cylinder 14 during combustion is directed out through exhaust valve 156 and through exhaust passage 148 to turbine 176. Turbine 176 may be coupled to an exhaust aftertreatment device, such as a catalytic converter, to remove emissions from the exhaust before being discharged into the atmosphere.

[0060] In one example, pump 606 may be a pump for circulating coolant in a cooling circuit of an engine, such as in a pump of a low temperature cooling circuit of an engine system. Coolant circulating through cooling loop 602 may be diverted from the low temperature cooling circuit. For example, the low temperature cooling circuit may circulate coolant through a charge air cooler to cool compressed air being pressurized by a turbocharger. Pump 606 may be a merging point of cooling loop 602 and the low temperature cooling circuit, and the coolant flow may be diverted through a three-way valve ( Figure 6602 and the low temperature cooling circuit. In this way, the coolant flow can be split between the cooling loop 602 and the low temperature cooling circuit, or flow completely to one or the other. In one example, the three-way valve can be adjusted based on the cooling demand of the compressor (e.g., the three-way valve can be moved to a position where coolant flows through the cooling loop 602 in response to the temperature of the charge air or compressed charge air increasing to a threshold temperature). The pump 606 can be activated in response to engine operating conditions (such as engine speed and temperature). For example, if the engine load increases, the pump 606 can be turned on when the engine speed or temperature exceeds a preset threshold.

[0061] When the coolant is driven to flow by pump 606, due to the recirculation passage (such as Figures 3 to 4C The coolant may become hotter after passing through the cooling jacket 334 by transferring heat from the heated air recirculated through the recirculation passage 328 of the engine. The heated coolant leaving the cooling jacket 334 then flows to the heat exchanger 604, where heat is extracted from the coolant. In this way, when the coolant returns to the inlet end of the cooling jacket 334, the temperature of the coolant is lower than the temperature of the air flowing through the recirculation passage, and the coolant can continue to absorb heat from the heated recirculation air. The heat exchanger 604 may be a radiator (also configured to cool the coolant circulating in the engine), or the heat exchanger 604 may be a separate air-cooled or coolant-cooled heat exchanger.

[0062] The heat extracted from the heated air can be transferred through the walls of the outer casing of the compressor 174 and the shell of the cooling jacket 334. The shell of the cooling jacket 334 can be made of a material that easily conducts heat, such as metal. In order to maximize the surface area of ​​the cooling jacket 334 available for heat exchange, the cooling jacket 334 can be configured with internal ribs, such as Figure 7 A cross-sectional view 700 of an embodiment of the cooling tower 334 is shown.

[0063] The cross section 700 may be along Figure 6 , depicting a view of the cooling jacket 334 along a plane formed by the vertical direction and the horizontal direction. The cooling jacket 334 may contain a coolant located between the outer shell 702 and the inner shell 704. A plurality of ribs 706 may be evenly spaced apart, extending linearly between the outer shell 702 and the inner shell 704 of the cooling jacket 334, and extending along a length of the cooling jacket 334 defined by a lateral direction and coaxial with the central axis 306.

[0064] The plurality of ribs 706 may be formed of the same material as the outer shell 702 of the cooling jacket 334, such as a thermally conductive metal, to enable rapid heat transfer across the temperature difference between the heated air in the recirculation passage and the coolant in the cooling jacket. Heat may be conducted through the wall of the outer shell of the compressor 174 to the outer shell 702 of the cooling jacket 334 and the plurality of ribs 706. Convection generated by the movement of the coolant enables heat exchange from the outer shell 702 of the cooling jacket 334 and from the side surfaces 708 of the plurality of ribs 706 to the coolant. Thus, arranging the plurality of ribs 706 within the cooling jacket 334 increases the surface area of ​​the conductive material in contact with the coolant, which facilitates heat transfer from the hotter air in the recirculation passage to the cooler coolant in the cooling jacket 334.

[0065] As mentioned above, for FIG. 4A to FIG. 4C An embodiment of the set of guide blades, in Figure 7 In other examples of the embodiment of the cooling jacket 334 shown in FIG. 1 , the cooling jacket 334 may include a different number of ribs, which are included in the plurality of ribs 706. In alternative embodiments, the cooling jacket 334 may have a greater number of ribs than the plurality of ribs 706. Figure 7 706. In some embodiments, the present invention provides a plurality of ribs 706 having a plurality of ribs ...

[0066] In this way, the compressor can be configured to reduce the occurrence of surge by extending the surge limit using uncontrolled (or minimally controlled) fixed elements. Air can be recirculated through the recirculation passage, which reduces the pressure gradient across the compressor that causes surge. In addition, the efficiency of the compressor can be improved by cooling the air heated by compression in the recirculation passage, wherein the cooling jacket surrounds the recirculation passage. By including a set of guide vanes inside the recirculation passage, the contact between the air and the surface of the recirculation passage cooled by the cooling jacket is extended, thereby allowing more heat transfer from the heated air to the coolant flowing through the cooling jacket. The cooling jacket may include a plurality of ribs that increase the surface area across which heat exchange can occur, thereby further contributing to increasing the density of the pressurized air delivered from the compressor to the engine. In some cases, a combination of a set of guide vanes arranged in the recirculation passage and cooling the recirculation passage by the cooling jacket can increase the compressor efficiency by 5-8%. The technical effect of cooling the recirculated air during low mass flow through the compressor is to minimize the possibility of compressor surge while enhancing the power output and fuel economy of the engine.

[0067] Figures 1 to 7An exemplary configuration with relative positioning of various components is shown. In at least one example, if it is shown as directly contacting each other or directly connected, such elements can be referred to as directly contacting or directly connected, respectively. Similarly, in at least one example, the elements shown as connected or adjacent to each other can be connected or adjacent to each other, respectively. As an example, the components laid in coplanar contact with each other can be referred to as being in coplanar contact. As another example, in at least one example, the elements positioned to be separated from each other and having only space between them without other components are referred to as such. As another example, the elements shown as being above / below each other, on the opposite sides of each other, or on the left / right sides of each other can be referred to as such relative to each other. In addition, as shown in the figure, in at least one example, the topmost element or the vertex of the element can be referred to as the "top" of the component, and the bottommost element or the bottommost point of the element can be referred to as the "bottom" of the component. As used herein, top / bottom, upper / lower, above / below can be relative to the vertical axis of the accompanying drawings and are used to describe the positioning of the elements of the accompanying drawings relative to each other. Thus, in one example, the element shown as being above other elements is positioned above other elements in the vertical direction. As yet another example, the shapes of elements depicted in the figures may be referred to as having those shapes (e.g., such as being annular, straight, planar, curved, rounded, chamfered, angled, etc.). Additionally, in at least one example, elements shown as intersecting each other may be referred to as intersecting elements or intersecting each other. Additionally, in one example, elements shown as being within another element or shown as being outside another element may be referred to as being such.

[0068] As an example, a method includes flowing intake air through a compressor intake passage to an impeller; recirculating a portion of the intake air from the impeller back to an inlet of the compressor intake passage via a set of guide vanes positioned in a recirculation passage circumferentially surrounding the compressor intake passage; and cooling the recirculated intake air in the recirculation passage via a cooling jacket circumferentially surrounding the recirculation passage. In a first example of the method, recirculating the portion of the intake air from the impeller back to the inlet of the compressor intake passage via the set of guide vanes positioned in the recirculation passage includes recirculating the portion of the intake air from the impeller through a bleed port of a sleeve at least partially surrounding the impeller, the bleed port being fluidly coupled to the recirculation passage. A second example of the method optionally includes the first example, and also includes wherein cooling the recirculated intake air in the recirculation passage via the cooling jacket includes directing the recirculated intake air along an inner surface of a compressor casing wall via the set of guide vanes, the cooling jacket being positioned in the compressor casing wall. A third example of the method optionally includes one or more of the first and second examples and further includes wherein cooling the recirculated intake air in the recirculation passage via the cooling jacket includes flowing coolant from a pump through the cooling jacket and to a heat exchanger. A fourth example of the method optionally includes one or more of the first to third examples and further includes wherein flowing coolant through the cooling jacket includes flowing coolant along a plurality of ribs positioned within the cooling jacket.

[0069] As an example, a compressor includes an impeller that can rotate about a central axis and is contained in a compressor housing; a sleeve that at least partially surrounds the impeller, the sleeve including a discharge port; a cooling jacket that is positioned in a wall of the compressor housing; a recirculation passage that is defined by an inner surface of the wall of the compressor housing and an outer surface of the sleeve, the recirculation passage being fluidly coupled to the discharge port; and a set of guide vanes that are positioned in the recirculation passage and extend along at least a portion of the cooling jacket. In a first example of the compressor, the cooling jacket includes a plurality of ribs disposed between an inner shell and an outer shell of the cooling jacket. A second example of the compressor optionally includes the first example and further includes wherein each of the plurality of ribs of the cooling jacket extends at least along a portion of the length of the cooling jacket. A third example of the compressor optionally includes one or more of the first and second examples and further includes wherein the recirculation passage circumferentially surrounds the sleeve and the wall of the compressor housing circumferentially surrounds the recirculation passage, and the cooling jacket extends circumferentially around the recirculation passage. The fourth example of the compressor optionally includes one or more of the first to fourth examples and further includes wherein each guide vane in the set of guide vanes extends across a width of the recirculation passage, the width being defined between the inner surface of the wall of the compressor housing and the outer surface of the sleeve in a direction perpendicular to the central axis of the compressor. The fifth example of the compressor optionally includes one or more of the first to fourth examples and further includes wherein the set of guide vanes includes a first guide vane having a wide end in contact with the inner surface of the wall of the compressor housing and a wedge-shaped end in contact with the outer surface of the sleeve. The sixth example of the compressor optionally includes one or more of the first to fifth examples and further includes wherein the first guide vane is bent in a clockwise direction from the wedge-shaped end to the wide end and is bent outwardly away from the central axis. The seventh example of the compressor optionally includes one or more of the first to sixth examples and further includes wherein the first guide vane is bent in a counterclockwise direction from the wedge-shaped end to the wide end and is bent inwardly toward the central axis. An eighth example of the compressor optionally includes one or more of the first to seventh examples and also includes wherein the set of guide vanes includes a first guide vane that is straight and has a uniform thickness and extends linearly between the inner surface of the wall of the compressor housing and the outer surface of the casing.A ninth example of the compressor optionally includes one or more of the first to eighth examples and further includes wherein the first guide vane has a depth defined along the central axis extending from an upstream end of the casing to an edge of the bleed port. A tenth example of the compressor optionally includes one or more of the first to ninth examples and further includes wherein the first guide vane has a depth extending along a portion of the length of the recirculation passage.

[0070] As another example, a compressor includes an impeller that can rotate about a central axis and is housed in a compressor housing; a sleeve that at least partially surrounds the impeller, the sleeve including a discharge port; a cooling jacket positioned in a wall of the compressor housing, the cooling jacket including an inner shell, an outer shell, and a plurality of ribs, each rib extending linearly between the outer shell and the inner shell and extending along the length of the cooling jacket; a recirculation passage defined by an inner surface of the wall of the compressor housing and an outer surface of the sleeve, the recirculation passage being fluidly coupled to the discharge port; and a set of guide vanes positioned in the recirculation passage and extending along at least a portion of the cooling jacket and dividing the inner volume of the recirculation passage into individual chambers. In a first example of the compressor, a first individual chamber of the recirculation passage is formed by a first guide vane surface of a first guide vane in the set of guide vanes, a second guide vane surface of a second guide vane in the set of guide vanes, the outer surface of the sleeve, and the inner surface of the wall of the compressor housing. A second example of the compressor optionally includes the first example and further includes wherein each guide vane in the set of guide vanes includes an airfoil shape. A third example of the compressor optionally includes one or more of the first example and the second example and further includes wherein each guide vane in the set of guide vanes includes a rectangular cross-sectional shape.

[0071] It should be noted that the exemplary control and estimation routines included herein can be used with various engine and / or vehicle system configurations. The control methods and routines disclosed herein can be stored as executable instructions in a non-transitory memory and can be implemented by a control system including a controller in combination with various sensors, actuators, and other engine hardware. The specific routines described herein may represent one or more of any number of processing strategies (such as event-driven, intermittently driven, multi-tasking, multi-threading, etc.). In this way, the various actions, operations, and / or functions shown may be performed in the order shown, may be performed in parallel, or in some cases, may be omitted. Similarly, the processing order is not necessarily required to achieve the features and advantages of the exemplary embodiments described herein, but is provided for ease of illustration and description. One or more of the actions, operations, and / or functions shown may be repeatedly performed depending on the specific strategy used. In addition, the described actions, operations, and / or functions may graphically represent the code in the non-transitory memory of a computer-readable storage medium to be programmed into the engine control system, wherein the described actions are implemented by executing the instructions in a system including various engine hardware components in combination with an electronic controller.

[0072] It should be understood that the configurations and routines disclosed herein are exemplary in nature, and these specific embodiments should not be considered in a limiting sense, as many variations are possible. For example, the above technology can be applied to V-6, inline 4, inline 6, V-12, opposed 4, and other engine types. The subject matter of the present disclosure includes all novel and non-obvious combinations and sub-combinations of the various systems and configurations and other features, functions, and / or characteristics disclosed herein.

[0073] The following claims particularly point out certain combinations and subcombinations that are considered novel and non-obvious. These claims may refer to "an" element or "a first" element or the equivalent thereof. Such claims should be understood to include the incorporation of one or more such elements, neither requiring nor excluding two or more such elements. Other combinations and subcombinations of the disclosed features, functions, elements, and / or characteristics may be claimed by amendment of the present claims or by presenting new claims in this or a related application. Such claims are also considered to be included in the subject matter of the present disclosure, whether broader, narrower, the same, or different in scope than the original claims.

[0074] According to the present invention, a method includes flowing intake air through a compressor intake passage to an impeller; recirculating a portion of the intake air from the impeller back to an inlet of the compressor intake passage via a set of guide vanes positioned in a recirculation passage circumferentially surrounding the compressor intake passage; and cooling the recirculated intake air in the recirculation passage via a cooling jacket circumferentially surrounding the recirculation passage.

[0075] According to one embodiment, recirculating the portion of the intake air from the impeller back to the inlet of the compressor intake passage via the set of guide vanes positioned in the recirculation passage comprises recirculating the portion of the intake air from the impeller through a bleed port of a casing at least partially surrounding the impeller, the bleed port being fluidly coupled to the recirculation passage.

[0076] According to one embodiment, cooling the recirculated intake air in the recirculation passage via the cooling jacket comprises directing the recirculated intake air along an inner surface of a compressor casing wall via the set of guide vanes in which the cooling jacket is positioned.

[0077] According to one embodiment, cooling the recirculated intake air in the recirculation passage via the coolant jacket comprises flowing a coolant from a pump through the coolant jacket and to a heat exchanger.

[0078] According to one embodiment, flowing the cooling liquid through the cooling jacket includes flowing the cooling liquid along a plurality of ribs positioned within the cooling jacket.

[0079] According to the present invention, a compressor includes an impeller, which can rotate about a central axis and is accommodated in a compressor housing; a sleeve, which at least partially surrounds the impeller, and the sleeve includes a discharge port; a cooling jacket, which is positioned in the wall of the compressor housing; a recirculation passage, which is defined by the inner surface of the wall of the compressor housing and the outer surface of the sleeve, and the recirculation passage is fluidly connected to the discharge port; and a set of guide vanes, which are positioned in the recirculation passage and extend along at least a portion of the cooling jacket.

[0080] According to one embodiment, the cooling jacket comprises a plurality of ribs arranged between an inner shell and an outer shell of the cooling jacket.

[0081] According to one embodiment, each rib of the plurality of ribs extends at least along a portion of the length of the cooling jacket.

[0082] According to one embodiment, the recirculation channel circumferentially surrounds the sleeve and the wall of the compressor housing circumferentially surrounds the recirculation channel, and the cooling jacket extends circumferentially around the recirculation channel.

[0083] According to one embodiment, each guide vane of the set of guide vanes extends across a width of the recirculation channel, the width being defined between the inner surface of the wall of the compressor housing and the outer surface of the sleeve in a direction perpendicular to a central axis of the compressor.

[0084] According to one embodiment, the set of guide vanes comprises a first guide vane having a wide end in contact with the inner surface of the wall of the compressor casing and a wedge-shaped end in contact with the outer surface of the sleeve.

[0085] According to one embodiment, the first guide vane bends in a clockwise direction from the wedge-shaped end to the wide end and outwardly away from the central axis.

[0086] According to one embodiment, the first guide vane bends in a counterclockwise direction from the wedge-shaped end to the wide end and inwardly towards the central axis.

[0087] According to one embodiment, the set of guide vanes comprises a first guide vane which is straight and has a uniform thickness and extends linearly between the inner surface of the wall of the compressor casing and the outer surface of the sleeve.

[0088] According to one embodiment, the first guide vane has a depth, which is defined along the central axis, extending from the upstream end of the sleeve to the edge of the bleed port.

[0089] According to one embodiment, the first guide vane has a depth extending along a portion of the length of the recirculation channel.

[0090] According to the present invention, a compressor includes an impeller, which is rotatable about a central axis and is accommodated in a compressor housing; a sleeve, which at least partially surrounds the impeller, and the sleeve includes a discharge port; a cooling jacket, which is positioned in the wall of the compressor housing, the cooling jacket including an inner shell, an outer shell and a plurality of ribs, each rib extending linearly between the outer shell and the inner shell and extending along the length of the cooling jacket; a recirculation passage, which is defined by the inner surface of the wall of the compressor housing and the outer surface of the sleeve, the recirculation passage being fluidly connected to the discharge port; and a set of guide vanes, which are positioned in the recirculation passage and extend along at least a portion of the cooling jacket and divide the inner volume of the recirculation passage into individual chambers.

[0091] According to one embodiment, the first single chamber of the recirculation channel is formed by a first guide vane surface of a first guide vane of the set of guide vanes, a second guide vane surface of a second guide vane of the set of guide vanes, the outer surface of the sleeve and the inner surface of the wall of the compressor casing.

[0092] According to an embodiment, each guide vane of the set of guide vanes comprises an airfoil shape.

[0093] According to an embodiment, each guide vane of the set of guide vanes comprises a rectangular cross-sectional shape.

Claims

1. A method for a compressor, the method comprising: allowing intake air to flow through the compressor intake passage to the impeller; recirculating a portion of the intake air from the impeller back to an inlet of the compressor intake passage via a set of guide vanes positioned in a recirculation passage circumferentially surrounding the compressor intake passage; as well as Recirculating intake air in the recirculation passage is cooled via a cooling jacket circumferentially surrounding the recirculation passage, the cooling jacket extending from a first port positioned upstream of the impeller relative to the flowing intake air to a second port positioned upstream of the first port relative to the flowing intake air.

2. The method of claim 1 , wherein recirculating the portion of the intake air from the impeller back to the inlet of the compressor intake passage via the set of guide vanes positioned in the recirculation passage comprises recirculating the portion of the intake air from the impeller through a bleed port of a casing at least partially surrounding the impeller, the bleed port being fluidly coupled to the recirculation passage.

3. The method of claim 2, wherein cooling the recirculated intake air in the recirculation passage via the cooling jacket comprises directing the recirculated intake air along an inner surface of a compressor casing wall via the set of guide vanes in which the cooling jacket is positioned. 4 . The method of claim 1 , wherein cooling the recirculated intake air in the recirculation passage via the coolant jacket comprises flowing a coolant from a pump, through the coolant jacket, and to a heat exchanger. 5 . The method of claim 4 , wherein flowing the cooling liquid through the cooling jacket comprises flowing the cooling liquid along a plurality of ribs positioned within the cooling jacket.

6. A compressor comprising: an impeller rotatable about a central axis and received in the compressor housing; a casing at least partially surrounding the impeller, the casing including a drain port; a cooling jacket positioned in a wall of the compressor housing, the cooling jacket extending from a first port positioned upstream of the impeller relative to the flowing intake air to a second port positioned upstream of the first port relative to the flowing intake air; a recirculation passage defined by an inner surface of the wall of the compressor housing and an outer surface of the sleeve, the recirculation passage fluidly coupled to the bleed port; as well as A set of guide vanes are positioned in the recirculation passage and extend along at least a portion of the cooling jacket.

7. The compressor of claim 6, wherein the cooling jacket includes a plurality of ribs disposed between an inner shell and an outer shell of the cooling jacket, and wherein each of the plurality of ribs of the cooling jacket extends along at least a portion of the length of the cooling jacket.

8. The compressor of claim 6, wherein said recirculation passage circumferentially surrounds said sleeve and said wall of said compressor housing circumferentially surrounds said recirculation passage, and said cooling jacket extends circumferentially about said recirculation passage.

9. The compressor of claim 6, wherein each guide vane of the set of guide vanes extends across a width of the recirculation passage, the width being defined between the inner surface of the wall of the compressor housing and the outer surface of the sleeve in a direction perpendicular to a central axis of the compressor.

10. The compressor of claim 9, wherein said set of guide vanes includes a first guide vane having a wide end in contact with said inner surface of said wall of said compressor housing and a tapered end in contact with said outer surface of said sleeve.

11. The compressor of claim 10, wherein said first guide vane curves in a clockwise direction from said tapered end to said wide end and outwardly away from said central axis.

12. The compressor of claim 10, wherein said first guide vane curves in a counterclockwise direction from said tapered end to said wide end and inwardly toward said central axis.

13. The compressor of claim 9, wherein said set of guide vanes includes a first guide vane that is straight and has a uniform thickness and extends linearly between said inner surface of said wall of said compressor housing and said outer surface of said sleeve.

14. The compressor of claim 10, wherein said first guide vane has a depth defined along said central axis extending from an upstream end of said sleeve to an edge of said bleed port.

15. The compressor of claim 10, wherein said first guide vane has a depth extending along a portion of a length of said recirculation passage.

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