Reduction of charge air cooler (CAC) corrosion using grille closures

Abstract

Method for controlling the radiator grille latches (114) of a vehicle (102), comprising the following: Adjusting the radiator grille closure opening in response to a location of condensate (312, 318) in an intercooler (18, 302, 304) that remains within a position range for longer than a threshold duration, wherein the radiator grille closures (114) are adjusted to move the location of condensate (312, 318) to an inlet of the intercooler (18, 302, 304) during a first set of conditions and to move the location of condensate (314, 318) to an outlet during a second, different set of conditions.

Description

BACKGROUND AND SUMMARY

[0001] Turbocharged engines use a charge air cooler (CAC) to cool the compressed air from the turbocharger before it enters the engine. Ambient air from outside the vehicle passes over the CAC to cool the intake air passing through its interior. When the ambient air temperature decreases, or during humid or rainy weather conditions, condensation can form inside the CAC if the intake air cools below the water dew point. If the intake air contains recirculated exhaust gases, the condensate can become acidic and corrode the CAC housing. This corrosion can lead to leaks between the intake air, the atmosphere, and, in the case of water-to-air coolers, potentially the coolant.The condensate can accumulate at the bottom of the CAC and then be drawn into the engine all at once during acceleration, increasing the possibility of engine misfire.

[0002] Other attempts to address condensation include restricting the intake air moving through the CAC or restricting the flow of ambient air to the CAC. An exemplary approach is shown by Craig et al. in US 6,408,831 B1. In this application, the intake air temperature is controlled by an ambient air flow restriction system and an intake air flow restriction system. A controller defines the position of these restriction devices and is connected to several sensors that measure various variables, such as the ambient and intake air temperatures. Additionally, US 8,020,536 B2 discloses a cooling device for a motor vehicle that includes an intercooler with a first cooling element and an EGR cooler with a second cooling element, wherein the first and second cooling elements are arranged side by side and substantially in the same plane.and wherein the respective cooling elements each have pipes for the medium to be cooled and air channels arranged between the pipes for a cooling airflow, comprising: a shielding device arranged in front of or behind the cooling elements to regulate the airflow through the cooling elements, and a control mechanism by which the shielding means can be switched back and forth between an open position, in which the shielding means does not restrict the airflow through the air passages of the cooling elements or at least not significantly, and a closed position, in which the shielding means restricts the airflow through the air passages between all pipes of the second cooling element and the airflow through the air passages between only some of the pipes of the first cooling element, in order to counteract ice formation in these pipes.

[0003] However, the inventors have recognized potential problems with such systems. In particular, the control of the restriction devices described above, in response to the temperature of the intake or ambient air, can reduce the overall level of condensate while potentially increasing the acid concentration in the condensate that forms. Maintaining temperatures at a certain level, so that condensation is low, can lead to maintaining a flow restriction for a period of time. This keeps the effectiveness of the charge air cooler / CAC at a certain level, causing the dew point to fluctuate at a specific location within the CAC. This can lead to an increased acid concentration in that area and actually create a higher risk of corrosion.This is because the risk of corrosion is highest in the CAC where the charge air temperature falls below the dew point and the water begins to condense, creating a highly concentrated water and acid solution, especially if the condensate level is kept low.

[0004] According to the invention, methods for controlling the radiator grille closures of a vehicle are provided, comprising the features of independent claims 1, 10 and 16.

[0005] In one example, the problems described above can be addressed by a method for controlling a vehicle's grille closures, where the method involves adjusting the grille closure opening in response to a location of condensate in an intercooler that remains within a position range for longer than a threshold duration. The grille closures can be adjusted during a first set of conditions to move the location of condensate toward an inlet of the intercooler (e.g., by increasing the closure opening), and can be adjusted during a second, different set of conditions to move the location of condensate toward an outlet (e.g., by decreasing the closure opening). In this way, it is possible, for example, to move the location of condensation, e.g.,Moving back and forth, if the location becomes stationary, may reduce the risk of corrosion at any given location from the inlet to the outlet of the charge air cooler.

[0006] It should be self-evident that the above summary is intended to introduce, in simplified form, a selection of the concepts that are further described in the detailed description. It is not intended to identify key or essential features of the claimed subject matter, the scope of which is clearly defined by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that eliminate all the disadvantages mentioned above or in any part of this disclosure. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 shows a schematic graphic representation of a radiator grille closure system, a power unit and the associated components in a vehicle. Fig. Figure 2 shows an example of the position of the CAC, radiator and engine within a vehicle in relation to the radiator grille closures and the associated ambient airflow. Fig. Figure 3 shows a schematic example of the location and movement of the dew point within the CAC. Fig. Figure 4 shows a detailed flowchart of a procedure for adjusting the radiator grille closure position based on a state of a non-powered vehicle, condensation in the CAC, external weather conditions, and engine temperatures. Fig. Figure 5 shows a flowchart of a procedure for adjusting a radiator grille closure position based on condensation within the CAC. Fig. Figure 6 shows a flowchart of a procedure for adjusting a radiator grille closure position based on the condensation conditions determined from the external weather conditions. Fig. Figure 7 shows a graphical comparison example of the radiator grille closure operation due to the engine coolant temperature, vehicle speed, condensation, and external weather conditions. DETAILED DESCRIPTION

[0007] The following description refers to systems and procedures for adjusting a vehicle's radiator grille closures in response to the cooling parameters of the engine, condensation in a CAC (cooling air conditioning system), and the conditions of a non-powered vehicle. The operation of the radiator grille closure for a vehicle's engine system, such as the engine system according to... Fig. 1. It can increase engine cooling, reduce condensation in the CAC, and optimize the vehicle's fuel economy. Opening the radiator grille latches, such as those found in Fig. As shown in Figure 2, the airflow through the front of the vehicle increases, directing a cooling airflow to the radiator and the CAC. Adjusting the airflow to the CAC via the grille vents can improve the CAC's efficiency by shifting the dew point location (as shown in Figure 2). Fig. (as shown in 3) and consequently reduce corrosion. A power machine controller can be configured to execute a control routine, such as the routine following the Fig. 4-6, to adjust the radiator grille closure opening based on the state of a non-powered vehicle, condensation in the CAC, external weather conditions, and engine temperatures. This can reduce condensation, CAC corrosion, and engine misfires. Example radiator grille closure settings in response to engine coolant temperature, vehicle speed, condensation, and external weather conditions are described with reference to Fig. 7 described.

[0008] Fig. Figure 1 shows a schematically illustrated exemplary embodiment of a radiator grille closure system 110 and a power unit system 100 in a motor vehicle 102. The power unit system 100 can be included in a vehicle, such as a road vehicle, together with other vehicle types. While the example applications of the power unit system 100 are described in relation to a vehicle, it should be recognized that various types of power units and vehicle propulsion systems can be used, including passenger cars, trucks, etc.

[0009] In the illustrated embodiment, the engine 10 is a turbocharged engine coupled to a turbocharger 13, which includes a compressor 14 driven by a turbine 16. Specifically, fresh air is introduced into the engine 10 via an inlet duct 42 through the air purifier 11 and flows to the compressor 14. The compressor can be a suitable intake air compressor, such as an engine-driven or driveshaft-driven supercharger. In the engine system 100, the compressor is shown as a turbocharger compressor mechanically coupled to the turbine 16 via a shaft 19, with the turbine 16 being driven by the expanding engine exhaust. In one embodiment, the compressor and the turbine can be coupled within a twin-scroll turbocharger.In another embodiment, the turbocharger can be a variable geometry turbocharger (VGT), in which the turbine geometry is actively varied as a function of the engine speed and other operating conditions.

[0010] As in Fig. As shown in Figure 1, the compressor 14 is coupled to a throttle valve 20 via an intercooler (CAC) 18. The throttle valve 20 is coupled to the engine intake manifold 22. The compressed air flows from the compressor through the intercooler and the throttle valve to the intake manifold. The intercooler can be, for example, an air-to-air or an air-to-water heat exchanger. In the Fig. In the embodiment shown in Figure 1, the pressure of the air charge within the inlet manifold is sampled by an manifold manifold pressure sensor (MAP sensor) 24. A compressor bypass valve (not shown) can be connected in series between the inlet and outlet of the compressor 14. The compressor bypass valve can be a normally closed valve configured to open under selected operating conditions to relieve excess boost pressure. For example, the compressor bypass valve can be open during deceleration of the engine speed to prevent compressor surging.

[0011] The inlet manifold 22 is coupled to a series of combustion chambers 31 via a series of (not shown) inlet valves. The combustion chambers are further coupled to an exhaust manifold 36 via a series of (not shown) exhaust valves. In the illustrated embodiment, a single exhaust manifold 36 is shown. In other embodiments, however, the exhaust manifold can contain multiple exhaust manifold sections. Configurations with multiple exhaust manifold sections can allow the exhaust from different combustion chambers to be directed to different locations in the engine system.

[0012] As in Fig. As shown in Figure 1, the exhaust gas from one or more exhaust manifold sections is directed to the turbine 16 to drive the turbine.

[0013] If reduced turbine torque is desired, some exhaust gas can instead be routed through a (not shown) boost pressure control valve, bypassing the turbine. The combined flow from the turbine and the boost pressure control valve then flows through an exhaust aftertreatment device 70. In general, one or more exhaust aftertreatment devices 70 can include one or more exhaust aftertreatment catalysts configured to catalytically treat the exhaust flow, thereby reducing the amount of one or more substances in the exhaust flow.

[0014] All or part of the treated exhaust gas from the exhaust gas purification device 70 can be discharged into the atmosphere via an exhaust line 35. Depending on the operating conditions, however, some exhaust gas can instead be directed to the EGR channel 51, through the EGR cooler 50 and the EGR valve 52 to the compressor inlet 14. In this way, the compressor is configured to draw in the exhaust gas tapped downstream of the turbine 16. The EGR valve can be opened to supply a controlled amount of the cooled exhaust gas to the compressor inlet for desired combustion and exhaust gas purification performance. In this way, the engine system 100 is designed to provide external low-pressure EGR (LP-EGR). The rotation of the compressor, in addition to the relatively long LP-EGR flow path in the engine system 100, provides excellent homogenization of the exhaust gas in the intake air charge.Furthermore, the arrangement of the EGR extraction point and the EGR mixing points provides effective cooling of the exhaust gas for an increased available EGR mass and improved performance.

[0015] The motor vehicle 102 further includes a cooling system 104, which circulates a coolant through the internal combustion engine 10 to absorb the waste heat, and which distributes the heated coolant via the coolant lines 82 and 84 to the radiator 80 and / or the heating element 90. In particular, it shows Fig. 1. The cooling system 104 is coupled to the engine 10, and the engine coolant circulates from the engine 10 via an engine-driven water pump 86 to the radiator 80 and back to the engine 10 via the coolant line 82. The engine-driven water pump 86 can be coupled to the engine via the front accessory drive (FEAD) 88 and rotated proportionally to the engine speed via a belt, chain, etc. Specifically, the engine-driven water pump 86 circulates the coolant through the channels in the engine block, head, etc., to absorb the engine heat, which is then transferred to the ambient air via the radiator 80.In an example where the water pump 86 driven by the engine is a centrifugal pump, the generated pressure (and the resulting flow) can be proportional to the crankshaft speed, which in the example is shown in . Fig. 1 is directly proportional to the engine speed. In another example, a motor-controlled pump can be used, which can be adjusted independently of the engine speed. The coolant temperature can be regulated via a thermostatic valve 38, which is located in the coolant line 82 and can be kept closed until the coolant reaches a threshold temperature.

[0016] Furthermore, a blower 92 can be coupled to the radiator 80 to maintain airflow through the radiator 80 when the vehicle 102 is moving slowly or is stopped while the engine is running. In some examples, the blower speed can be controlled by a controller 12, which is described in more detail below. Alternatively, the blower 92 can be coupled to an engine accessory drive system driven by the engine crankshaft.

[0017] The coolant can flow through coolant line 82, as described above, and / or through coolant line 84 to the heating core 90, where heat can be transferred to a passenger compartment 106, with the coolant flowing back to the engine 10. In some examples, the water pump 86, driven by the engine, can be operated to circulate the coolant through both coolant lines 82 and 84.

[0018] Fig. Figure 1 further shows a control system 28. The control system 28 can be communicatively coupled to various components of the power machine system 100 in order to execute the control routines and actions described here. As in Fig. As shown in Figure 1, the control system 28 can, for example, include an electronic digital controller 12. The controller 12 can be a microcomputer containing a microprocessor unit, input / output ports, an electronic storage medium for executable programs and calibration values, a read / write memory, a hold memory, and a data bus. As shown, the controller 12 can receive inputs from several sensors 30, including user inputs and / or sensors (such as the gear position of the transmission, the accelerator pedal input, the brake input, the automatic transmission shift lever position, the vehicle speed, the engine speed, the mass airflow through the engine, the ambient temperature, the ambient humidity, the intake air temperature, the fan speed, etc.), the cooling system sensors (such as the coolant temperature, the fan speed, the passenger compartment temperature, the ambient humidity, etc.), and the sensors of the CAC 18 (such as...).B. the temperature and pressure of the CAC's intake air, the temperature and pressure of the CAC's exhaust air, etc.) and other data. Furthermore, the controller can receive data from the GPS 34 and / or a communication and entertainment system 26 within the vehicle 102.

[0019] The communication and entertainment system 26 within the vehicle can communicate with a wireless communication device 40 via various wireless protocols, such as wireless networks, cellular tower transmissions, and / or combinations thereof. The data received by the communication and entertainment system 26 within the vehicle can include real-time and predicted weather conditions. Weather conditions, such as temperature, precipitation (e.g., rain, snow, hail, etc.), and humidity, can be obtained through various applications of the wireless communication device and weather forecast websites. The data received by the communication and entertainment system within the vehicle can include current and predicted weather conditions for both the current location and future locations along a planned route.In one embodiment, where the in-vehicle communication and entertainment system includes a GPS, current and future weather data can be correlated with current and future routes displayed on the GPS. In an alternative embodiment, where the vehicle system includes a dedicated GPS 34, both the GPS and the in-vehicle communication and entertainment system can communicate with the wireless communication device 40 and with each other to transmit current and future weather data along with current and future routes. For example, the entertainment system can access various weather maps stored on the internet or in cloud computing systems. The stored weather maps may contain rain, humidity, precipitation, and temperature information, provided, for example, as contour maps.In one example, the wireless communication device 40 can transmit real-time humidity data to the vehicle's communication and entertainment system 26 and / or the GPS 34, which is then forwarded to the controller 12. The controller 12 compares the received humidity data with threshold values ​​and determines the appropriate radiator grille closure setting. If the humidity is, for example, greater than a defined threshold value, one or more of the radiator grille closures can be closed.

[0020] In addition to receiving humidity data from the vehicle's communication and entertainment system 26 and GPS 34, the controller 12 can receive humidity data from alternative or additional sensors. These may include humidity sensors or humidity measurements from an intake O2 sensor. The controller 12 can also derive humidity from multiple sensors or vehicle system signals. These may include rain sensors, windshield wiper on / off signals, a universal exhaust oxygen sensor (UEGO sensor), and a fuel shut-off system during deceleration (DFSO system). The controller can use one or more of these sensors or signals to determine the humidity and then adjust the radiator grille closing system accordingly.

[0021] Furthermore, the controller 12 can communicate with various actuators 32, which may include power engine actuators (e.g., fuel injectors, an electronically controlled intake air throttle plate, spark plugs, etc.), cooling system actuators (such as air handling vents and / or blow-off valves in the passenger compartment climate control system, etc.), and others. In some examples, the storage medium may be programmed with computer-readable data that reproduces the instructions executable by the processor to perform both the procedures described below and other variations that may be expected but are not specifically listed.

[0022] As indicated here, the amount of waste heat transferred from the engine to the coolant can change with operating conditions and thereby influence the amount of heat transferred to the airflow. For example, if the engine output torque or fuel flow is reduced, the amount of waste heat generated can decrease proportionally.

[0023] The motor vehicle 102 further includes a radiator grille 112, which provides an opening (e.g., a grille opening, a bumper opening, etc.) for receiving an airflow 116 through or near the front of the motor vehicle and into the engine compartment. Such an airflow 116 can then be used by the radiator 80 and other components to keep the engine and / or transmission cool. Furthermore, the airflow 116 can dissipate heat from the vehicle's air conditioning system and can improve the performance of turbocharged / supercharged engines equipped with the CAC 18, which reduces the temperature of the air entering the intake manifold / engine. Fig. Figure 2 shows an example of the locations of the CAC 18, the radiator 80, and the engine system 100 within a vehicle 102 with respect to the radiator grille closures and the associated flow 116 of ambient air. The other components under the hood (the fuel system, batteries, etc.) can also benefit from the cooling airflow. Consequently, the radiator grille closure system 110 can assist the cooling system 104 in cooling the internal combustion engine 10. The radiator grille closure system 110 comprises one or more radiator grille closures 114 configured to adjust the amount of airflow received through the radiator grille 112.

[0024] The grille closures 114 can cover a front area of ​​the vehicle, extending, for example, from just under the hood to the underside of the bumper. Covering the CAC inlet reduces flow resistance and decreases the entry of external cooling air into the CAC. In some embodiments, all grille closures can be moved in coordination with the controller. In other embodiments, the grille closures can be divided into sub-areas, and the controller can independently adjust the opening / closing of each area. For example, a first area might contain the grille closures that largely affect flow resistance, while others affect the entry of air into the CAC.In one example, the first sub-area can extend from just below the hood to the top of the bumper, while the second sub-area can extend from the top of the bumper to the bottom of the bumper. Each sub-area can contain one or more grille latches. In some examples, each area can contain the same number of grille latches, while in other examples, one sub-area contains more than the other. In one embodiment, the first sub-area can contain multiple grille latches, while the second sub-area contains one grille latch. In an alternative embodiment, the first sub-area can contain only one grille latch, while the second sub-area contains multiple grille latches.

[0025] The radiator grille latches 114 are movable between an open position and a closed position, and can be held in any position or several intermediate positions. In other words, the opening of the radiator grille latches 114 can be adjusted so that the radiator grille latches 114 are partially open, partially closed, or cycle between an open position and a closed position to provide airflow for cooling the engine compartment components with the least loss of fuel economy. This is because closing and / or partially closing the radiator grille latches 114 reduces the amount of airflow taken in by the radiator grille 112 and consequently reduces the vehicle's drag.Maintaining the grille closures in an open position allows for adequate engine cooling; however, this can also increase drag on the vehicle and reduce fuel economy. Conversely, closing the grille closures reduces drag and improves fuel economy; however, this may not allow for adequate engine cooling. Consequently, the control of the grille closures can be based on several vehicle operating conditions, which are discussed further below. In some embodiments, the grille closures may be used solely for controlling CAC condensate. In this case, operating the grille closures may offer little to no aerodynamic advantage.

[0026] In some embodiments, the control system 28 can be configured to adjust the opening of the grille latches 114 in response to the vehicle's operating conditions. Adjusting the opening of the grille latches 114 can include opening one or more of the grille latches, closing one or more of the grille latches, partially opening one or more of the grille latches, partially closing one or more of the grille latches, adjusting the timing of the opening and closing, etc. For example, the controller 12 can be communicatively connected to the grille latch system 110, and instructions for adjusting the opening of the grille latches 114 can be stored in it.

[0027] The radiator grille closures can be adjusted in response to various system variables, including engine temperatures, vehicle driving conditions, condensation in the coolant accumulator (CAC), and external weather conditions. One or more of the radiator grille closures may open in response to any of the above variables, even if the other variables remain within normal ranges. This allows all variables to be evaluated to determine the optimal radiator grille closure opening for vehicle cooling, preventing CAC corrosion, avoiding misfires, and improving fuel economy.

[0028] Under certain conditions, the radiator grille locking system 110 can be adjusted in response to the vehicle's driving states, such as whether the vehicle is in a driven or undriven state. The driven state may include when the wheels exert a positive force that propels the vehicle forward. The undriven state may include when the wheels absorb the vehicle's inertia and generate a negative force opposing the vehicle's forward motion. In one embodiment, the undriven state may include a deceleration state, a braking state, a pedal release state, a combination thereof, or another state type that signals that an undriven state is occurring or about to occur. For example, an automatic cruise control braking signal may also be used.Furthermore, global positioning signals can be used, which indicate a slower area ahead, an approach to a slope, etc.

[0029] In some cases, the vehicle may be switched off during deceleration, disengaging the transmission from the engine to improve fuel economy. In this situation, additional engine cooling is required. Opening the radiator grille vents at the beginning of deceleration can pre-cool the engine, keeping engine temperatures low. This can also allow the radiator grille vents to remain closed for a longer period during subsequent acceleration, reducing the vehicle's drag and further improving fuel economy.

[0030] Furthermore, the radiator grille closure system 110 can be adjusted to modify condensation within the CAC 18. Several sensors 30 and the controller 12 monitor both the location of the dew point within the CAC 18 and other corrosion risk factors (such as the duration of the dew point remaining at a particular location within the CAC). Consequently, in one example, one or more radiator grille closures can be adjusted in response to the dew point remaining static at a particular location for too long. By adjusting the radiator grille closures in this way, it is possible to move the dew point to a different location within the CAC 18 to reduce corrosion. For example, if the dew point has remained static at a location within the CAC for longer than a predetermined time limit, the radiator grille closures 114 can change their position to alter the effectiveness of the CAC 18. This moves the location of the dew point. A further illustration of this is shown in Fig. 3 is shown and described below. The position of the radiator grille latches 114 can be further modified by current or predicted weather conditions. Adjusting the closing of one or more of the radiator grille latches 114 can, for example, be done in response to condensation-forming weather conditions. Condensation-forming weather conditions can include rain, humidity, cool temperatures, or a combination thereof. Weather conditions can be provided via the vehicle's communication and entertainment system 26 or the GPS 34.

[0031] Furthermore, in some embodiments, the degree of adjustment of the radiator grille shutters 114 can depend on the condition of a non-powered vehicle, the location of the dew point, or the degree of condensation-forming weather conditions, or combinations thereof. For example, during a longer deceleration, the degree of opening of the radiator grille shutters 114 can be increased and / or the opening time of the radiator grille shutters 114 can be brought forward, allowing a greater airflow to aid in cooling the engine, thus extending subsequent acceleration with the radiator grille shutters closed. As another example, the opening of the radiator grille shutters 114 can be reduced if the vehicle's GPS 34 or communication and entertainment system 26 predicts a small amount of rain and only moderately humid conditions.

[0032] Furthermore, in some embodiments, the radiator grille closure system 110 can be adjusted based on the engine temperature, the state of a non-powered vehicle, and condensation within the CAC 18. For example, the controller 12 can be configured to monitor the engine temperature, e.g., to monitor a coolant temperature and compare it to threshold values. Additional methods for adjusting the radiator grille closure system 110 are described with reference to the Fig. 4-6 are described in more detail. Adjusting the radiator grille closures in this manner provides sufficient engine cooling while reducing the vehicle's drag, minimizing condensation, and preventing dew point buildup in the CAC. This can improve the vehicle's fuel economy and help prevent corrosion of the CAC and engine misfires.

[0033] Fig. Figure 3 shows a schematic example of the location and movement of the dew point within the CAC. Figure 300 shows two CAC examples with varying amounts of condensate. In the first CAC, 302, hot charge air from the compressor 306 enters the CAC and cools as it moves through the CAC, then exits 310 to pass through the throttle valve 20 and into the engine intake manifold 22. The ambient air flow 308 enters through the radiator grille closure openings and moves laterally through the CAC to assist in cooling the charge air. The location 312 of the dew point is near the proximal end of the CAC. A highly concentrated water and acid solution can form at this point, posing the greatest significant risk of corrosion. Downstream of the dew point location 312, a relatively large amount of condensate 314 forms in the CAC 302.By adjusting the position of the radiator grille latches 114, the ambient air flow 308 is altered, consequently changing the effectiveness of the CAC and shifting the dew point location. In the example of CAC 302, closing one or more of the radiator grille latches results in a reduced ambient air flow 308, a decrease in the cooling effectiveness of CAC 302, and a downward movement of the dew point in the horizontal direction. The new location 316 of the dew point is shown in CAC 304. In this case, the charge air temperatures are warmer, which reduces the amount of condensate 318 in CAC 304.

[0034] Several approaches can be used to control the radiator grille latches. As with regard to Fig. As further described in section 3, the radiator grille closures can be adjusted based on the location of condensation within a CAC. For example, if the dew point within a CAC remains within a position range along the horizontal axis for longer than a threshold duration, the radiator grille closure position can be adjusted to move the condensation location depending on various factors, as described therein. This position range can be adjusted based on the vehicle's operating conditions. For example, if engine temperatures are high and require the radiator grille closures to be open more frequently, this position range can be increased to allow for additional engine cooling. Conversely, if the ambient air temperature is low or it is currently raining, this position range can be decreased to prevent corrosion of the CAC.The threshold duration described above can be a period of time, a number of miles, a number of engine revolutions, or another measurable parameter.

[0035] With reference to Fig. 3. The control system 28 can calculate the location of the dew point, determine the desired direction for moving it along the horizontal axis, and adjust it in response to the position of the radiator grille latches. For example, if the dew point is located to the left of a predetermined center position, the radiator grille latches can be closed to reduce cooling and move the dew point to the right 322. Conversely, if the dew point is located to the right of the predetermined center position, the radiator grille latches are opened to increase cooling and move the dew point to the left 320. In this way, moving the dew point to the right and causing the radiator grille latches to open also results in increased cooling of the engine.By shifting the dew point to the left and causing the radiator grille shutters to close, the vehicle's drag is reduced, thereby improving fuel economy. Consequently, controlling the radiator grille shutters in this way can reduce the deterioration of the CAC (cooling air control valve) while simultaneously improving fuel economy and aiding engine cooling.

[0036] In Fig. Procedure 400 is an example procedure for adjusting the radiator grille closure position based on a non-powered vehicle condition, condensation in the CAC, external weather conditions, and engine temperatures. Procedure 402 involves estimating and / or measuring engine operating conditions. These include, for example, engine speed and load, torque demand, boost pressure, manifold pressure (MAP), manifold-to-air charge temperature (MCT), air-fuel ratio (lambda), fuel-alcohol content, atmospheric pressure, ambient conditions (e.g., ambient air temperature, pressure, and humidity), engine pre-ignition history, etc. Procedure 404 can determine, based on the estimated conditions, whether a non-powered vehicle condition exists.Such a determination may involve detecting a non-propelled vehicle condition, such as a deceleration condition, a braking condition, a pedal release condition, a rate of change of engine speed less than a predetermined threshold, a braking signal from an adaptive cruise control system (which senses the distance to a vehicle directly in front of the vehicle in question and automatically applies the vehicle's brakes to maintain a threshold separation from the preceding vehicle), or another type of condition that signals a non-propelled vehicle condition. For example, a non-propelled vehicle condition may be present when the amount of time the driver depressed the brake pedal exceeds a threshold. Another example is when the driver's braking force (e.g.,A force applied to the brake pedal exceeds a threshold value. Another example is when a non-powered vehicle is in a state where the brake pressure exceeds a threshold value. Yet another example is when the degree of application of the vehicle's brakes (e.g., electrically operated brakes) exceeds a threshold value.

[0037] If the vehicle is not in a non-powered vehicle state (e.g., the vehicle is powered), then procedure 400 transitions to 406, where the controller sets the grille base closure position to closed. However, if the vehicle is in a non-powered vehicle state, then procedure 400 transitions to 408, where the controller sets the grille base closure position to open. From both 406 and 408, procedure 400 transitions to 410, where condensation in the CAC is assessed. This procedure is discussed in the following. Fig. 5. This is discussed in more detail below. If it is determined at 410 that no condensate is forming, then procedure 400 continues at 412 to maintain the radiator grille closure position in the base position. However, if it is determined at 410 that condensate is forming, procedure 400 continues at 414 to determine the radiator grille closure setting required to reduce or change the condensate formation. At 416, the setting is made, and the new position is set as the radiator grille base position. At 418, the routine determines the probability of condensate forming in the CAC based on the external weather conditions. This procedure is further explained below. Fig. 6. If, based on weather conditions, CAC condensate is not likely to form, the radiator grille latches are maintained in the set base position. However, if condensate is likely to form, the radiator grille latches are closed, replacing the previous base position. Procedure 400 continues at 424 to check the engine temperatures against the threshold values. For example, if the engine coolant temperature (ECT) rises above a maximum value, engine cooling assistance is required. If these temperatures are not above a threshold, the radiator grille latches are maintained in the set base position, and the routine ends. However, if the temperatures are above the threshold values, the radiator grille latches are opened, and the routine ends.

[0038] In Fig. Figure 5 shows an example procedure 500 for adjusting the radiator grille closure position based on condensation within the CAC. At 502, the routine determines the conditions of the CAC. This may involve retrieving details such as the ambient air temperature, ambient air humidity, inlet and outlet charge air temperature, and inlet and outlet charge air pressure from several sensors 30. These variables are used at 504 to determine whether condensation is forming in the CAC. If no condensation is forming, the procedure maintains the current radiator grille closure position and then terminates. However, if condensation is forming, the procedure proceeds to 508 to determine the location of the dew point within the CAC. The controller 12 can determine the location of the dew point by analyzing both the conditions of the CAC, as described above, and other variables (such as...Vehicle speed, fan speed, radiator grille closure position, etc.) are determined. The controller can use algorithms to analyze the data and determine the location of the dew point, the duration the dew point remained at that position, the amount of condensate within the CAC, and other values. If the time spent at the dew point exceeds a predetermined time limit, the procedure at 514 determines the direction in which the dew point is moving (as described above and in ). Fig. (Figure 3 illustrates this). At 516, the controller 12 and the actuators 32 adjust the radiator grille closure orientation to move the dew point to the desired location. Once the radiator grille closures have been adjusted, the routine ends.

[0039] In Fig. Figure 6 shows an example procedure 600 for adjusting the radiator grille closure position based on condensation conditions determined from external weather conditions. In Figure 602, the controller 12 receives data from several sensors 30, a GPS 34, and the vehicle's communication and entertainment system 26. The recovered data may include the ambient air temperature and humidity, and the predicted weather conditions for the road ahead or along the vehicle's route. In Figure 604, the controller 12 then analyzes the data for the conditions that lead to CAC condensation. These conditions may include rain, high humidity, low air temperature, or a combination thereof. In Figure 606, if the condensation conditions are determined to be above the threshold values, the radiator grille closures are closed.Otherwise, the procedure maintains the current grille closure position. The thresholds can include a specified temperature, a specified percentage of humidity, or a specified amount of precipitation at which condensation is likely to form within the CAC. The routine ends after steps 610 and 608.

[0040] Fig.Figure 7 shows a graphical example comparison 700 of the radiator grille closure operation based on engine coolant temperature, vehicle speed, condensation, and external weather conditions. The example compares graphical representations 702 and 704 for a scenario of vehicle speed (VS) and external weather conditions (OC) as a function of time. Graphical representation 702 illustrates a first example operation of the radiator grille closures independent of condensation (CF). The opening and closing of the radiator grille closures is based on the engine temperature and a state of a non-powered vehicle, represented in this figure as an engine coolant temperature (ECT) and a vehicle speed, respectively.Alternatively, graphic illustration 704 illustrates a second example of an adjustable radiator grille closure system, in which the operation of the radiator grille closures is based on the engine coolant temperature, vehicle deceleration, condensation formation and external weather conditions.

[0041] Referring to graph 702, the CF curve reaches a threshold just before time t1. However, the engine coolant temperature exceeds a threshold T2 at this point, causing the radiator grille closures to open. This causes the CF curve to dip below the CT line before corrosion risk conditions are reached. The closures remain open, with condensation increasing above the CT line, until at time t2 the engine coolant temperature falls below another threshold T1. At time t3, the vehicle speed indicates deceleration or braking, signaling the opening of the radiator grille closures. During this period, the engine coolant temperature continues to fall, and condensation once again rises above the CT line.At time t4, the vehicle accelerates, and the engine misfires at 710 due to increased condensation. As the vehicle continues to accelerate, the engine coolant temperature rises along with the condensation. At time t5, the radiator grille latches open after the engine coolant temperature reaches T2.

[0042] Referring to graphic 704, the radiator grille closures open again when the engine coolant temperature exceeds the threshold value T2 at time t1. Subsequently, condensation increases above the threshold value CT. The closures remain closed until time t 1' Open if the CF curve remained above CT during the specified time limit Δt2. The radiator grille latches are opened at t 1' closed, which allows condensation to decrease again. Between t 1'At t3, the external weather conditions change to those likely to produce condensation. Because the grille shutters are already closed, they remain closed at 728. The grille shutters open again at t3 in response to vehicle deceleration and remain open until t4 as the vehicle accelerates. It is important to note that engine misfire does not occur at 722 in this example because the condensate level in the CAC has been kept low due to the earlier changes in the grille shutter position. At t4, the grille shutters open again in response to the CF curve rising above CT during the specified time limit Δt3. At t5, the external weather conditions change once more to those likely to produce condensation. This causes the grille shutters to close at 730.The radiator grille latches remain closed while the engine coolant temperature slowly rises to T2 at time t6, causing the radiator grille latches to open for the last time.

[0043] Comparing graphs 702 and 704 reveals differences in condensation within the CAC. In graph 702, the CF curve rises above the condensation threshold four times, with three of these instances representing a significant corrosion risk to the CAC (712, 714, and 716). However, in graph 704, the time the CF curve spends above the condensation threshold is reduced (724 and 726). Consequently, controlling the grille closures in response to condensation and external weather conditions reduces the risk of corrosion and condensation within the CAC. Furthermore, in graph 704 (718, 720, 734, and 736), the grille closures remain closed for more time than in graph 702 (706, 708, and 732). This also reduces aerodynamic drag on the vehicle, improving fuel economy.

[0044] As described above, the grille shutter orientation can be controlled in response to engine temperatures, vehicle driving conditions, condensation within the CAC, and external weather conditions. The grille shutters open, cooling engine system components, if the dew point within the CAC needs to be shifted to the left, if engine temperatures are high, or if the vehicle is in a non-powered state, such as deceleration. The grille shutters close, cutting off the flow of cooling air, if the dew point within the CAC needs to be shifted to the right, if there are condensation-forming weather conditions, or if the vehicle is powered.Controlling the radiator grille closures in this way allows for adequate cooling of the engine, while optimizing the vehicle's fuel economy, preventing engine misfires, and preventing CAC corrosion.

[0045] As an average professional in the field will recognize, the routines described herein may represent one or more of any number of radiator grille latch setting controls. As such, the various steps or functions illustrated may be performed in the illustrated order, in parallel, or, in some cases, omitted. Likewise, the order of control is not necessarily required to achieve the tasks, features, and benefits described herein, but is provided for the ease of illustration and description. Although not explicitly illustrated, an average professional in the field will recognize that one or more of the illustrated steps or functions may be performed repeatedly, depending on the particular strategy employed.

[0046] The subject matter of the present disclosure includes all novel and non-obvious combinations and sub-combinations of the various processes, systems and configurations, as well as any further features, functions, actions and / or properties disclosed herein, and any and all equivalents thereof. Reference symbol list 10 Power machine 11 air purifiers 12 controllers 13 turbochargers 14 Compressor 16 Turbine 18 Intercoolers (CAC) 19th wave 20 Throttle valve 22 Engine intake manifolds 24 Manifold air pressure sensor (MAP sensor) 26 Communication and entertainment system 28 Tax system 30 sensors 31 Combustion chamber 32 Actuator 34 GPS 38 Thermostatic valve 40 Communication device 42 Inlet channel 51 EGR channel 50 EGR coolers 52 EGR valve 70 Exhaust gas purification device 80 coolers 82, 84 Coolant line 86 Water pump 88 Front Accessory Drive (FEAD) 90 heating core 92 blowers 100 power machine system 102 motor vehicle 104 Cooling system 106 occupant compartment 110 Radiator grille locking system 112 Radiator grille 114 radiator grille latches 116 Airflow 300 intercooler / CAC examples 302, 304 intercooler / CAC 306 Compressor 308 Flow 310 Exiting the charge air cooler / CAC 312 Location of the dew point 314 Condensate 316 new location of the dew point 318 Condensate 320 Movement of the dew point to the left 322 Movement of the dew point to the right

Claims

A method for controlling the radiator grille closures (114) of a vehicle (102), comprising: adjusting the radiator grille closure opening in response to a location of condensate (312, 318) in an intercooler (18, 302, 304) that remains within a position range for longer than a threshold duration, wherein the radiator grille closures (114) are adjusted to move the location of condensate (312, 318) to an inlet of the intercooler (18, 302, 304) during a first set of conditions and to move the location of condensate (314, 318) to an outlet during a second, different set of conditions. Method according to claim 1, wherein the first set of conditions comprises that the location of the condensate (312, 318) is closer to the outlet than to the inlet, or wherein the first set of conditions comprises that the location of the condensate (312, 318) is closer to the inlet than to the outlet. Method according to claim 1, wherein the first set of conditions comprises that the engine temperature is higher than a threshold value, and the second set of conditions comprises that the engine temperature is lower than the threshold value. Method according to claim 1, wherein moving the location towards the inlet comprises enlarging the closure opening and moving towards the outlet comprises decreasing the closure opening. Method according to claim 1, wherein the first set of conditions comprises that a pedal release by the driver occurs, and the second set of conditions comprises a vehicle acceleration driven by the power engine (10). The method according to claim 1, further comprising adjusting the radiator grille closures (114) in response to the cooling parameters of the power unit (10) and the driver releasing the pedal. Method according to claim 5, wherein the position range is increased in response to an increased engine temperature. Method according to claim 5, which further comprises charging the intake air upstream of the charge air cooler (18, 302, 304). Method according to claim 1, further comprising the direct injection of the fuel into a power engine (10) of the vehicle (102). Method for controlling the radiator grille closures of a vehicle (102), the method comprising: enlarging the radiator grille closure opening in response to a location of condensation in an intercooler (18, 302, 304) and to an engine temperature above a threshold or to vehicle deceleration conditions; and decreasing the radiator grille closure opening in response to the location of condensation and to the engine temperature below the threshold or to vehicle acceleration conditions. The method of claim 10, further comprising adjusting the radiator grille closure opening in response to the surrounding weather conditions specified by a communication system (26) in the vehicle (102), wherein the communication system (26) receives the information sent from outside to the vehicle (102). Method according to claim 11, wherein the surrounding weather conditions include the humidity of the ambient air. The method of claim 10, further comprising keeping the radiator grille closures (114) closed during the acceleration state, and wherein the radiator grille closures (114) are fully open during the deceleration states immediately preceding the acceleration states, even if the engine temperature should be below the threshold. The method of claim 13, further comprising adjusting the radiator grille closures (114) in response to an estimated amount of condensation in the charge air cooler (18, 302, 304). Method according to claim 13, which further comprises switching off the power engine (10) during the deceleration. Method for controlling the radiator grille closures (114) of a vehicle (102), the method comprising: adjusting the radiator grille closure opening in response to a location of the condensate (312, 318) in an intercooler (18, 302, 304) that remains stationary for longer than a threshold duration, including enlarging the radiator grille closure opening in response to a first condition and decreasing the radiator grille closure opening in response to a second condition different from the first condition, wherein the radiator grille closures (114) are adjusted to move the location of the condensate (312, 318) to an inlet of the intercooler (18, 302, 304) during the first condition and to move the location of the condensate (314, 318) to an outlet during the second condition. The method of claim 16, further comprising adjusting the radiator grille closures (114) in response to the cooling parameters of the engine (10) and the driver releasing and pressing the pedal, wherein the position range is increased in response to an increased engine temperature.

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