JP2009002346A - Method for thermally managing engine and engine system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for thermally managing an engine, capable of reducing fuel consumption by reducing friction in the engine and capable of reducing engine oil consumption by increasing durability of engine oil. <P>SOLUTION: A first coolant circuit 109 is disposed in an engine 101. A second coolant circuit 111 having heat exchangers 110, 116, a refrigerant pump 112, a temperature sensing means 115, and a valve means 117 is connected to the first coolant circuit 109. In the thermal management method of the engine 101, the refrigerant pump 112 is controlled such that a temperature Tin of a coolant supplied from the second coolant circuit 111 to the first coolant circuit 109 is lower than a temperature Tout of a coolant discharged from the first coolant circuit 109 to the second coolant circuit 111 by at least 10°C, and a refrigerant flow is generated with a coolant thereof having a temperature of more than 90°C at a cylinder head 106. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an engine thermal management method. More specifically, an engine block having a coolant passage therein, a cylinder head fixed to the engine block and having a coolant passage therein, and the coolant passages A heat exchanger connected to the first coolant circuit for extracting heat from the coolant, a refrigerant pump for generating a refrigerant flow in the coolant circuit, and temperature detection means And a thermal management method for an engine provided with a second coolant circuit comprising valve means. The present invention further relates to an engine system comprising the above-described engine and at least one engine control unit configured to perform such a method.

  Prior to the present invention, various engine cooling systems or thermal management systems have developed various refrigerant circuits to improve the operation of the engine as well as the operation of associated units such as passenger compartment heaters and window glass defrosters. It has been conceived with the composition of In particular, when the engine is cold during cold start, fuel consumption increases due to increased friction in the engine, resulting in increased engine emissions.

  Temperature is an important factor for reducing friction and it is therefore desirable to use engine heat in the most effective manner. During the warm-up phase (before completion of warm-up), heat is absorbed mainly by the engine block. Rapidly warming the passenger compartment in cold weather has become an eternal challenge for automakers.

  However, many solutions today require expensive additional equipment.

  Patent Document 1 discloses an engine thermal management system provided with a heating acceleration circuit that promotes engine warm-up.

  During the warm-up phase, the coolant circuit only includes a refrigerant pump, a refrigerant flow path located on the exhaust side of the cylinder head, and a heat exchanger for warming the passenger compartment.

Patent Document 2 describes an engine cooling system. It includes an initial engine warm-up channel that extends from the refrigerant pump, through a cooling passage in the cylinder head, through a heat exchanger used to warm the passenger compartment, and back to the refrigerant pump. . Thereby, during the warm-up phase, a temperature responsive flow control valve or thermostat inhibits coolant from flowing from the cylinder head to the cooling passage in the engine block.

U.S. Pat. No. 6,089,077 discloses an engine having a heat distribution circuit comprising a radiator, a latent heat store, a pump, and a balancing container. During cold start, the valve is configured to stop the coolant from flowing into the crankcase, and the balance vessel and latent heat storage are connected in series between the cylinder head and the pump. The aim is to ensure that the cylinder head warm-up during cold start is as quick as possible.

  U.S. Patent No. 6,057,836 where the main cooling circuit receives the refrigerant from the heat exchanger and pumps the refrigerant first through the engine block, then through the cylinder head and back to the heat exchanger. An engine having a main pump is described. For quick warm-up, during the warm-up phase, the main refrigerant circuit is shut off and the refrigerant is pumped by an electric pump through a sub-cooling circuit that passes only through the cylinder head. The sub-cooling circuit has a heat accumulator, a heat exchanger, and a room heater.

  Patent Document 5 discloses a liquid-cooled engine having a refrigerant chamber in a cylinder block and a cylinder head. The refrigerant chamber is connected to a refrigerant circulation pump via an adjusting device controlled according to temperature. When the coolant is higher than the predetermined temperature, the coolant is circulated through both the cylinder head and the cylinder block, while when lower than the predetermined temperature, the coolant is circulated only through the cylinder head. .

  Patent Document 6 discloses a method for sufficiently cooling a cylinder by shortening the engine warm-up time in cold by using cooling water for cooling the cylinder head and lubricating oil for cooling the cylinder block. It is described. The cooling water passage circulates between the cylinder head and the radiator so that the cooling water is circulated by the pump.

Non-Patent Document 1 discloses an electric water pump system in which the electric water pump is stopped for a very short time so as to improve the warm-up performance of the refrigerant and oil.
U.S. Pat.No. 5,735,238 U.S. Pat.No. 5,337,704 German Patent Application Publication No. 4,105,199 German Patent Application No. 4,032,701 U.S. Pat.No. 4,319,547 JP 57-193712 A Ulrich Hess et al. "Das Warmemanagement des neuen BMW-Reihen sechs zylindermotors", German magazine MTZ (MOTORTECHNISCHE ZEITSCHRIFT) 11/2005, Jahrgang 66, pp 872-877

  However, many of the above solutions require the provision of additional equipment, such as additional pumps or additional coolant, which adversely affects engine assembly and increases costs.

  Accordingly, it is an object of the present invention to improve engine thermal management and overcome the above-mentioned drawbacks.

  The above objective is accomplished by providing a method for thermal management of an engine in a warm-up completion state as defined in claim 1 of the claims.

In the conventional engine, the temperature T _{out of the} coolant discharged from the first coolant circuit to the second coolant circuit is about 90 ° C., and the cooling supplied from the second coolant circuit to the first coolant circuit since the temperature T _in the liquid was about 85 ° C., and the temperature T _in the cooling liquid from the second liquid coolant circuits are supplied to the first coolant circuit, the discharge from the first coolant circuit to the second coolant circuit The difference ΔT with _respect to the temperature T _{out of the} coolant was about 5 ° C.

  According to the present invention, ΔT is at least 10 ° C., which represents a small flow rate of coolant such that the temperature of the coolant in the cylinder head is maintained above 90 ° C., which is higher than in conventional engines.

  By keeping the temperature of the coolant in the cylinder head above 90 ° C., the friction in the engine, in particular the friction between the piston and the cylinder wall, is further reduced, resulting in lower fuel consumption.

  In addition, heat increases engine oil consumption because oil degradation is enhanced by heat. Due to the small flow rate of coolant defined by ΔT ≧ 10 ° C., cooler coolant enters the engine compared to the prior art.

  As cold coolant enters the engine, the engine oil in the oil sump is kept cool compared to the prior art, which results in a lower temperature of the engine oil, thereby reducing the engine oil. Durability is increased and oil consumption is therefore reduced. Preferably, the coolant inlet from the second coolant circuit to the first coolant circuit is installed in the engine block, i.e., when entering the engine, the coolant first enters the engine block and then Guided by the cylinder head.

  According to an advantageous embodiment of the method according to the invention, the refrigerant pump is controlled so as to produce a refrigerant stream such that the temperature of the coolant in the cylinder head is above 100 ° C.

  Experiments have shown that friction in the engine is further reduced above this temperature level, resulting in lower fuel consumption.

  According to another advantageous embodiment of the method according to the invention, the refrigerant pump is controlled so as to produce a refrigerant stream such that the temperature of the coolant in the cylinder head is above 105 ° C.

  Experiments have shown that friction in the engine is further reduced above this temperature level, resulting in a further reduction in fuel consumption.

  According to a further advantageous embodiment of the method according to the invention, the refrigerant pump is controlled so as to produce a refrigerant stream such that the temperature of the coolant in the cylinder head is between 110 ° C. and 120 ° C. Experiments have shown that friction in the engine is further reduced within this temperature range, leading to further reductions in fuel consumption.

According to another advantageous embodiment of the method according to the invention, the refrigerant pump is a refrigerant whose temperature (T _in ) of the coolant supplied from the second coolant circuit to the first coolant circuit is below 85 ° C. Controlled to generate a flow.

  The coolant having a temperature below this temperature level entering the engine further increases the durability of the engine oil and further reduces the oil consumption.

According to yet another advantageous embodiment of the method according to the invention, the refrigerant pump is such that the temperature (T _in ) of the coolant supplied from the second coolant circuit to the first coolant circuit is below 75 ° C. It is controlled to produce a refrigerant stream, preferably below 70 ° C, or even below 65 ° C.

  The entry of coolant at temperatures below these temperature levels into the engine is particularly preferred because a further increase in engine oil durability is achieved and oil consumption is further reduced.

  According to an advantageous embodiment of the method according to the invention, the refrigerant pump has a coolant flow rate rapidly when knocking occurs (e.g. when there is a risk or when it is actually detected). It is controlled to increase, whereby the cylinder head is rapidly cooled by the cold coolant supplied by the present invention, and rapid knock control is performed to prevent knocking.

  As a result of this efficient knock control, the temperature of the cylinder head can be maintained above the high temperature level described above without having any knock problems. The occurrence of knocking is detected and / or determined in a known manner.

  Furthermore, the above object is achieved by providing a method for thermal management of an engine before completion of warm-up as defined in claim 10 of the claims.

  Conventionally, most of the heat from combustion in the engine enters the cylinder head, and most of the heat transferred from the cylinder head to the engine block is transferred by the coolant. However, by controlling the refrigerant flow according to the method of the present invention, heat is retained in the cylinder head, and heat transfer through the coolant from the cylinder head to the engine block is greatly reduced.

  Due to the small flow rate of coolant defined by ΔT ≧ 10 ° C, cooler coolant enters the engine and the first coolant circuit compared to the case of a large flow rate coolant defined by a smaller ΔT. , Thereby transferring less heat to the engine block per unit mass flow rate of the coolant. If the engine is provided with a first coolant circuit that allows the internal flow of coolant from the cylinder head to the engine block, heat transfer through the coolant within the engine will also be Due to the refrigerant flow, it is greatly reduced.

  If the second coolant circuit includes only the refrigerant pump and does not include the heat exchanger, heat is extracted from the coolant flowing in the second coolant circuit mainly by the pipe or tube of the second coolant circuit. is there.

  When the coolant flow rate (flow velocity) in the second coolant circuit is small, the coolant stays in the pipe or tube for a long time, so the heat transfer from the coolant through the pipe or tube per unit mass flow rate of the coolant The size is increased, thus providing a greater coolant temperature drop, ie, a greater ΔT.

When the coolant flow rate (flow velocity) in the second coolant circuit is large, the coolant stays in the pipe or tube for a short time, so the unit mass of the coolant from the coolant existing in the pipe or tube The heat transfer per flow rate is reduced, thus providing a smaller coolant temperature drop, ie, a smaller ΔT. This is true even when the second coolant circuit includes one or more heat exchangers, in which case these heat exchangers also extract heat from the coolant.
On the other hand, when the flow rate of the coolant is large, the total amount of heat transferred from the second coolant circuit is large because the total amount of the coolant passing through the second coolant circuit per unit time is large.

  The present invention is instead achieved by rapid warm-up of the cylinder head resulting in rapid warm-up of the coolant, cylinder head, piston, and cylinder, thereby providing a cold start, especially during cold weather. Friction and fuel consumption are reduced without any additional devices such as additional pumps or sub-coolant circuits.

  In this way, the method can be applied to existing engines without substantial equipment replacement or addition.

  Experiments have shown that this method not only heats fresh air and reduces throttle loss, but also reduces friction in the valve train and piston ring, improving fuel efficiency by 4%, and reducing coolant The warm-up phase can be accelerated.

  Experiments have shown that a significant increase in the coolant temperature occurs, but the decrease in engine oil temperature is limited to a small amount.

  This is because engine oil is heated during the warm phase in a much hotter cylinder head.

  Preferably, for active heating, heating of the moving engine oil can be included in the warm-up process.

  According to an advantageous embodiment of the method according to the invention, the refrigerant pump is prevented from pumping the coolant until at least the temperature of the coolant in the cylinder head reaches 100 ° C. The refrigerant pump is controlled so as to generate the refrigerant flow.

  Experiments have shown that friction in the engine is further reduced above this temperature level, resulting in lower fuel consumption.

  According to a further advantageous embodiment of the method according to the invention, the refrigerant pump is prevented from pumping coolant until at least the temperature of the coolant in the cylinder head reaches 105 ° C. The refrigerant pump is controlled to generate a flow rate of refrigerant flow.

  Experiments have shown that friction in the engine is further reduced above this temperature level, resulting in a further reduction in fuel consumption.

  According to another advantageous embodiment of the method according to the invention, the refrigerant pump is prevented from pumping coolant until at least the temperature of the coolant in the cylinder head reaches 110 ° C. The refrigerant pump is controlled to generate a small flow rate of refrigerant flow.

  Experiments have shown that friction in the engine is further reduced above this temperature level, resulting in a further reduction in fuel consumption.

  According to a further advantageous embodiment of the method according to the invention, the coolant is pumped using a pump that is drivably decoupled from the engine.

  This pump can be an electric refrigerant pump or a mechanically driven refrigerant pump, such as, for example, a variable displacement pump, which can be drivably disconnected from the engine. However, other refrigerant pumps that can operate off the engine are also possible. For example, a mechanically driven refrigerant pump may be used that is configured “short-circuited”, ie, provided with an additional circuit connecting the pump outlet and the pump inlet.

  The above object is also achieved by providing a method for thermal management of an engine prior to completion of warm-up as defined in claim 16 of the claims.

  In a cold room at the time of cold start, the aim (object) of the present invention may be to quickly warm up the passenger compartment, not to accelerate engine warm-up.

  When the second coolant circuit is equipped with a heat exchanger that extracts heat from the coolant and warms the passenger compartment, the heat generated in the cylinder head retains as much heat as possible in the cylinder head Rather than aiming for it, it is removed from the coolant in a heat exchanger to warm the passenger compartment. However, since the coolant flow rate defined by ΔT ≧ 10 ° C. is again smaller than the coolant flow rate in the prior art, as described above, less energy or heat is transferred to the engine block, Instead, it is transmitted to the passenger compartment.

  In this way, all of the heat that would be transferred from the engine block to the atmosphere is instead available to warm the passenger compartment, so that the external heater in the diesel engine can be removed.

  According to a further advantageous embodiment of the method according to the invention, the coolant discharged from the coolant flow path of the cylinder head is guided to a heat exchanger for warming the passenger compartment.

  In this way, the coolant from the coolant to the engine block at the outlet of the first coolant flow path (since the coolant heated by the cylinder head enters the heat exchanger directly without going through the engine block) Heat transfer, and more heat can be extracted from the coolant into the passenger compartment heat exchanger.

  Further advantageous embodiments and aspects of the method according to the invention will become apparent from the detailed description of the preferred embodiments.

  As described above, the general inventive concept of the method of the present invention is significantly smaller than the prior art before the engine warm-up is completed (during the warm-up phase) or after the warm-up is completed (steady state). Supplying a flow rate of coolant or substantially stagnation of coolant in the engine during a significant portion of the engine warm-up phase or during the entire warm-up phase.

According to an advantageous embodiment of the above-described method according to the present invention, the refrigerant pump has a temperature (T _in ) of the coolant supplied from the second coolant circuit to the first coolant circuit from the first coolant circuit. Control is performed to generate a refrigerant flow that is at least 20 ° C. lower than the temperature (T _out ) of the coolant discharged to the second coolant circuit.

  Experiments have shown that the coolant flow rate at this level results in further reduced heat transfer to the engine block, with more heat being retained in the cylinder head or transferred to the passenger compartment. Become.

According to a further advantageous embodiment of the above-described method according to the invention, the refrigerant pump has a temperature (T _in ) of the coolant supplied from the second coolant circuit to the first coolant circuit so that the first coolant Control is performed to produce a refrigerant flow that is at least 30 ° C. lower than the temperature (T _out ) of the coolant discharged from the circuit to the second coolant circuit.

  Experiments have shown that the coolant flow rate at this level results in a further reduction in heat transfer to the engine block and more heat is retained in the cylinder head or transferred to the passenger compartment. Become.

  The method of the present invention is applicable to different types of coolant circuit configurations. For example, the warm-up phase may be applied to a sub-coolant circuit that circulates coolant only in the cylinder head without entering the engine block.

  Also, a first coolant circuit having an inlet for coolant provided in the cylinder head and / or engine block and / or an outlet for coolant provided in the cylinder head and / or engine block. The coolant may be pumped from the engine block to the cylinder head or vice versa.

  Furthermore, it may be applied to a second coolant circuit or a coolant circuit including an additional device included in the first coolant circuit.

  The method of the present invention is suitable for both gasoline and diesel engines, but especially during the warm-up phase of the diesel engine, because the combustion chamber is hot and the catalytic converter is quicker. It is particularly preferred because it is easily warmed up and thus reduces CO and HC emissions.

  The present invention also provides an engine system as defined in claim 21 of the claims.

  FIG. 1 schematically shows an engine system including an engine (internal combustion engine) 101 to which the method of the present invention can be applied.

  The engine 101 includes an engine block 102 having a coolant flow path 104 therein, a cylinder head 106 fixed to the engine block 102 and having a coolant flow path 108 provided therein, and a coolant flow. A first coolant circuit 109 is provided with paths 104 and 108. A second coolant circuit 111 connected to the first coolant circuit 109 is provided. The second coolant circuit 111 is a radiator-type heat exchanger 110 having an inlet and an outlet for extracting heat from the coolant, and an electric refrigerant having an inlet and an outlet for generating a refrigerant flow in the coolant circuit A pump 112, an oil cooler 116 for extracting heat from the engine oil, and a temperature detecting means 115 and a valve means 117 included in a thermostat 118 are provided.

  The electric refrigerant pump 112 is a pump that can operate independently of the operating state of the engine. In other words, the electric refrigerant pump 112 can be configured to be detachable from the engine.

  The temperature detection means 115 is configured to measure, among other things, the coolant temperature in the cylinder head 106. The coolant temperature in the cylinder head 106 may be measured, for example, by supplying a coolant leakage flow from the cylinder head and measuring the temperature of the leakage flow.

  Thermostat 118 is configured to receive coolant from radiator 110, engine 101, and oil cooler 116 via its two inlets and to control the refrigerant flow using valve means 117.

  In the coolant circuit for circulating the coolant, a portion existing inside the cylinder head or the engine block is defined as the first coolant circuit 109, and a portion existing outside is defined as the second coolant circuit 111. May be defined.

  The engine system further includes an engine control unit (ECU) 120. The engine control unit 120 may be a single unit or a plurality of physical units logically interconnected. The engine control unit 120 is configured to receive the data and control the electric refrigerant pump 112, the radiator 110, the oil cooler 116, and the thermostat 118.

  FIG. 2 schematically represents a flowchart of a first embodiment of a thermal management method for the engine 101 during cold start according to the present invention. In FIG. 2, steps 202 to 204 and 221 will be described below as a first viewpoint, steps 205 to 207 and 222 as a second viewpoint, and steps 208 to 213 and 223 to 224 as a third viewpoint. Each step in FIG. 2 is started every time the engine is started (from step 201), and these steps can always be executed during engine operation.

  At engine start-up, in step 201, during the warm-up phase, the refrigerant flow through the radiator 110 is stopped in a conventional manner by the valve means 117 of the thermostat 118.

  First, the first aspect will be described. In step 202, the ECU 120 controls the electric refrigerant pump 112 to stop, prevents the electric refrigerant pump 112 from pumping the coolant, and consequently the first coolant. The coolant is substantially stagnated in the circuit 109.

  In step 203, the coolant temperature in the cylinder head 106 is detected by the temperature detecting means 115 of the thermostat 118, and the ECU 120 receives this temperature data.

  In step 221, if the coolant temperature at the cylinder head is below 110 ° C., ECU 120 controls in step 202 to continue to stop electric refrigerant pump 112, thus preventing the coolant from being pumped. .

  Conversely, if in step 221 the coolant temperature at the cylinder head is greater than or equal to 110 ° C, the ECU 120 will maintain the coolant temperature at 110 ° C in the cylinder head 106 at step 204. The electric refrigerant pump 112 is controlled so as to generate a refrigerant flow to such an extent as possible in the coolant circuit.

Next, the second aspect (which may be selected alternatively to the first aspect) will be described. In step 205, the ECU 120 detects the temperature of the coolant supplied from the second coolant circuit 111 to the first coolant circuit 109. T _in is approximately 30 ° C. lower than the temperature T _{out of the} coolant discharged from the first coolant circuit 109 to the second coolant circuit 111, that is, ΔT = T _out −T _in ≈30 ° C. The electric refrigerant pump 112 is controlled so as to pump the coolant at the flow rate.

  In step 206, the coolant temperature in the cylinder head 106 is detected by the temperature detection means 115 of the thermostat 118, and the ECU 120 receives this temperature data.

In step 222, if the coolant temperature in the cylinder head 106 falls below 110 ° C., the ECU 120 sets the flow rate already set in step 205 (a flow rate such that ΔT = T _out −T _in ≈30 ° C.). Then, the electric refrigerant pump 112 is controlled so as to continue pumping the coolant.

  Conversely, if, at step 222, the coolant temperature at the cylinder head is greater than or equal to 110 ° C, the ECU 120 sets the coolant temperature at the cylinder head 106 to about 110 ° C at step 207. The electric refrigerant pump 112 is controlled to pump the coolant at a flow rate that is maintained at (the value determined at step 222), which at least initially increases the flow rate.

  In steps 221 and 222, it is determined whether or not the coolant temperature in the cylinder head is below 110 ° C., but this value can be changed.

  As one example, it may be determined whether the coolant temperature at the cylinder head is below 105 ° C.

  As another example, it may be determined whether the coolant temperature at the cylinder head is below 100 ° C.

  As a further example, it may be determined whether the coolant temperature at the cylinder head is below 90 ° C.

In a conventional engine, T _out is conventionally 90 ° C., T _in is conventionally 85 ° C., the difference between the T _out and T _in was not only 5 ° C. is set. According to the first embodiment of the present invention, when the outlet of the first coolant circuit 109 is provided in the cylinder head 106, T _out matches the coolant temperature in the cylinder head 106, and the cylinder head 106 When the coolant temperature at reaches 110 ° C., T _out is about 110 ° C.

  In FIG. 2, steps 204 and 207 of the first and second aspects of the thermal management method of the engine 101 during the engine warm-up phase are in a state where the engine is warmed up, that is, in a steady state (in other words, in a warm state). The process proceeds to the first step 208 of the third aspect of the thermal management method of the engine 101 in the machine completion state.

  In step 208, in the warm-up complete condition, refrigerant flow through the radiator 110 is allowed by the valve means 117 of the thermostat 118, if necessary, in a conventional manner.

In step 209, ECU 120 maintains the coolant temperature in the cylinder head 106 to 110 ° C., and the temperature T _in the cooling liquid from the second liquid coolant circuit 111 is supplied to the first coolant circuit 109 about 80 ° C. Therefore, the electric refrigerant pump 112 is controlled so that the coolant is pumped at such a flow rate that ΔT = T _out −T _in ≈30 ° C.

This, although the temperature T _in the cooling liquid from the second liquid coolant circuit 111 is supplied to the first coolant circuit 109 is controlled to be 80 ° C. at step 209, this value can be changed is there.

As an example, to produce a flow refrigerant flow in which the temperature T _in is below about 90 ° C., there is a case of controlling the electric coolant pump 112.

As another example, to produce a flow refrigerant flow in which the temperature T _in is below about 85 ° C., there is a case of controlling the electric coolant pump 112.

As one further example, to produce a flow refrigerant flow in which the temperature T _in is below about 75 ° C., in some cases to control the electric coolant pump 112.

  Further, the value of ΔT in step 209 can be arbitrarily changed. For example, the value may be set to a value (for example, 20 ° C.) smaller than the value of ΔT (for example, 30 ° C.) in step 205.

  If engine knocking does not occur in step 223, in step 210, the coolant temperature in the cylinder head 106 is detected by the temperature detecting means 115 of the thermostat 118, and the ECU 120 receives this temperature data.

  In step 224, if the coolant temperature in the cylinder head 106 is within the range of 110 ° C. to 120 ° C., in step 211, the ECU 120 causes the electric refrigerant pump to continue pumping the coolant at the same flow rate. 112 is controlled.

  Conversely, if the coolant temperature at the cylinder head 106 is outside that range (ie, less than 110 ° C or greater than 120 ° C) in step 224, the ECU 120 adjusts the coolant flow rate in step 212. Thus, the electric refrigerant pump 112 is controlled.

  For example, in step 212, if the coolant temperature is less than 110 ° C, the coolant flow rate may be decreased, and if the coolant temperature is 120 ° C or higher, the coolant flow rate may be increased. Control can be performed so that the liquid temperature returns within the range of 110 ° C to 120 ° C.

  In step 223, if engine knock occurs, the ECU 120 controls the electric refrigerant pump 112 in step 213 so that the coolant flow rate increases rapidly, so that the cylinder head 106 is cooled. Cooling is rapidly performed by the coolant, and quick knock control is performed.

  The determination of whether or not knocking occurs in step 223 may be based on whether or not knocking has actually been detected, or by calculating the risk of knocking (i.e., knocking possibility) It may be based on the calculation result.

  FIG. 3 represents a flowchart of a second embodiment of the method according to the invention. As disclosed in FIG. 2, the steps of the first aspect (steps 202 to 204 and 221) or the steps of the second aspect (steps 205 to 207 and 222) are executed during the engine warm-up phase. Instead, each step of the first aspect (steps 202 to 204 and 221) is performed first, then each step of the second aspect (steps 205 to 207 and 222) is performed, and then disclosed in FIG. Each step of the third aspect (steps 208 to 213 and 223 to 224) is executed.

  In another embodiment of the present invention, steps 201 to 204 and 221 (steps of the first aspect) and / or steps 201 and 205 to 207 and 222 (steps of the second aspect) are steps 208 to 213. And 223 to 224 (steps of the third viewpoint) may be executed without being performed.

In this case, in the warm-up completion state, ΔT = T _out −T _in can be configured to take a value of less than 10 ° C. (or less than 20 ° C., or less than 30 ° C.).

  In still another embodiment of the present invention, steps 208 to 213 and 223 to 224 (steps of the third aspect) are steps 201 to 204 and 221 (steps of the first aspect) and / or step 201. And 205 to 207 and 222 (each step of the second aspect) may be executed without executing them.

In this case, during the warm-up phase, ΔT = T _out −T _in can be configured to take a value of less than 10 ° C. (or less than 20 ° C., or less than 30 ° C.).

  Furthermore, the first and second aspects of the method according to the present invention are applied to the same engine system alternately or subsequently as disclosed in FIG. 3, or the first aspect of the method according to the present invention. One may choose to apply only one of the aspects and the second aspect.

  As one example, it is possible to combine each step of the first viewpoint during the warm-up phase and each step of the third viewpoint in the warm-up completion state.

  As another example, it is possible to combine each step of the second viewpoint during the warm-up phase and each step of the third viewpoint in the warm-up completion state.

  As a further example, depending on the driving state of the car, select only one of the first viewpoint and the second viewpoint during the warm-up phase, and each step and each of the third viewpoint in the warm-up completed state. Steps can be combined.

  For example, the first viewpoint is selected when the coolant temperature at engine startup is less than a predetermined temperature (for example, 70 ° C.), and the second viewpoint when the coolant temperature at engine startup is equal to or higher than a predetermined temperature (for example, 70 ° C.). May be selected. Preferably, the coolant temperature at the cylinder head is between 110 ° C. and 120 ° C. in a steady state (warm-up complete state). Therefore, in step 224, it is determined whether the coolant temperature at the cylinder head is between 110 ° C. and 120 ° C., but this value can be changed.

  As one example, it may be determined whether the coolant temperature at the cylinder head exceeds 105 ° C.

  As another example, it may be determined whether the coolant temperature at the cylinder head exceeds 100 ° C.

  As a further example, it may be determined whether the coolant temperature at the cylinder head exceeds 90 ° C.

  FIG. 4 schematically represents a second engine system comprising an engine (internal combustion engine) 401 to which the method of the invention can be applied.

  The engine 401 includes an engine block 402 having a coolant flow path 404 therein, a cylinder head 406 fixed to the engine block 402 and having a coolant flow path 408 provided therein, and a coolant flow. A first coolant circuit 409 having paths 404 and 408 is included. In this engine system, the first coolant circuit 409 has a plurality of flow paths (downward arrows) configured to guide coolant from the cylinder head 406 to the engine block 402 inside the engine.

  The engine system further includes a second heat exchanger 412 for extracting heat from the coolant and warming the passenger compartment.

  The second heat exchanger 412 receives the coolant discharged from the coolant flow path of the cylinder head 406 (by being guided by the second coolant passage 111).

  The other components of this engine system correspond to the components of the engine system of FIG. 1, and are denoted by the same reference numerals in FIG.

  Of course, the second heat exchanger 412 may be shown associated with them or may be irrelevant when applying the aspects disclosed in FIGS. 2 and 3.

According to a further embodiment of the present invention, the aim (objective) in the present invention is not to accelerate engine warm-up, but to warm the passenger compartment quickly, which is a particularly serious problem in cold rooms during cold start. In particular, the refrigerant pump 112 causes the temperature T _{in of the} coolant supplied from the second coolant circuit 111 to the first coolant circuit 409 to be changed from the first coolant circuit 409 to the second coolant circuit 111. Control is performed to generate a refrigerant flow that is approximately 25 ° C. lower than the temperature T _out of the discharged coolant. Since the flow rate of the coolant in the second heat exchanger 412 is small, the temperature of the coolant greatly decreases in the second heat exchanger 412.

  Although the coolant flow rate in this embodiment is high compared to the embodiment of FIGS. 2 and 3, it is still significantly lower than a conventional engine system that includes a heat exchanger that warms the passenger compartment.

  According to preferred embodiments of the invention, for all methods of the invention, ΔT (at least in steps 205 and 209) is at least 20 ° C., preferably at least 25 ° C., or even at least It can be 30 ° C.

  The present invention is not limited to the embodiment described above. It will be apparent that various modifications can be made without departing from the scope of the claims.

It is a schematic block diagram showing an engine system provided with the engine which can apply the method of the present invention. 2 is a schematic flow chart representing a first embodiment of a method according to the present invention. 4 is a schematic flow chart showing a second embodiment of a method according to the present invention. It is a schematic block diagram showing the 2nd engine system provided with the engine which can apply the method of the present invention.

Explanation of symbols

101, 401 engine
102, 402 engine block
104, 404 Coolant flow path
106, 406 cylinder head
108, 408 Coolant flow path
109, 409 First coolant circuit
110, 116, 412 heat exchanger
111 Second coolant circuit
112 Refrigerant pump
115 Temperature detection means
117 Valve means
118 Thermostat
120 Engine control unit

Claims (21)

A thermal management method for engines (101, 401),
The engine (101, 401)
An engine block (102, 402) having a coolant flow path (104, 404) therein;
A cylinder head (106, 406) fixed to the engine block (102, 402) and having a coolant flow path (108, 408) therein;
A first coolant circuit (109, 409) having each of the coolant channels (104, 108, 404, 408),
The first coolant circuit (109, 409) has a refrigerant flow in at least one heat exchanger (110, 116, 412) for extracting heat from the coolant and in the first coolant circuit (109, 409). A second coolant circuit (111) having a refrigerant pump (112) to be generated, a temperature detection means (115), and a valve means (117) is connected,
The temperature (T _in ) of the coolant supplied from the second coolant circuit (111) to the first coolant circuit (109, 409) is changed from the first coolant circuit (109, 409) to the second coolant circuit (109, 409). A refrigerant that is at least 10 ° C. lower than the temperature (T _out ) of the coolant discharged to the coolant circuit (111), and that the temperature of the coolant in the cylinder head (106, 406) exceeds 90 ° C. An engine heat management method comprising a step (209) of controlling the refrigerant pump (112) so as to generate a flow. The step (209) of controlling the refrigerant pump (112) includes:
The temperature (T _in ) of the coolant supplied from the second coolant circuit (111) to the first coolant circuit (109, 409) is changed from the first coolant circuit (109, 409) to the second coolant circuit (109, 409). It is a step of controlling the refrigerant pump (112) so as to generate a refrigerant flow that is at least 20 ° C. lower than the temperature (T _out ) of the coolant discharged to the coolant circuit (111). The engine thermal management method according to claim 1. The step (209) of controlling the refrigerant pump (112) includes:
The temperature (T _in ) of the coolant supplied from the second coolant circuit (111) to the first coolant circuit (109, 409) is changed from the first coolant circuit (109, 409) to the second coolant circuit (109, 409). It is a step of controlling the refrigerant pump (112) so as to generate a refrigerant flow that is at least 30 ° C. lower than the temperature (T _out ) of the coolant discharged to the coolant circuit (111). The engine thermal management method according to claim 2. The step (209) of controlling the refrigerant pump (112) includes:
4. The step of controlling the refrigerant pump (112) so as to generate a refrigerant flow in which the temperature of the coolant in the cylinder head (106, 406) exceeds 100 ° C. The engine thermal management method according to any one of the above. The step (209) of controlling the refrigerant pump (112) includes:
5. The step of controlling the refrigerant pump (112) so as to generate a refrigerant flow such that a temperature of a coolant in the cylinder head (106, 406) exceeds 105 ° C. Engine thermal management method. The step (209) of controlling the refrigerant pump (112) includes:
It is a step of controlling the refrigerant pump (112) so as to generate a refrigerant flow such that the temperature of the coolant in the cylinder head (106, 406) is between 110 ° C and 120 ° C. The engine thermal management method according to claim 5. The step (209) of controlling the refrigerant pump (112) includes:
The refrigerant is generated in such a way that a refrigerant flow having a temperature (T _in ) of the coolant supplied from the second coolant circuit (111) to the first coolant circuit (109, 409) is lower than 85 ° C. The engine thermal management method according to any one of claims 1 to 6, wherein the engine is a step of controlling the pump (112). The step (209) of controlling the refrigerant pump (112) includes:
The refrigerant is generated so as to generate a refrigerant flow in which the temperature (T _in ) of the coolant supplied from the second coolant circuit (111) to the first coolant circuit (109, 409) is less than 75 ° C. 8. The engine thermal management method according to claim 7, wherein the engine thermal management method is a step of controlling the pump (112).   The engine thermal management according to claim 7 or 8, further comprising a step (213) of controlling the refrigerant pump (112) so that the flow rate of the coolant rapidly increases when knocking occurs. Method. A thermal management method for engines (101, 401),
The engine (101, 401)
An engine block (102, 402) having a coolant flow path (104, 404) therein;
A cylinder head (106, 406) fixed to the engine block (102, 402) and having a coolant flow path (108, 408) therein;
A first coolant circuit (109, 409) having each of the coolant channels (104, 108, 404, 408),
The first coolant circuit (109, 409) includes a refrigerant pump (112), a temperature detection means (115), and a valve means (117) that generate a refrigerant flow in the first coolant circuit (109, 409). A second coolant circuit (111) having
The refrigerant pump (112) is prevented from pumping the coolant until at least the temperature of the coolant in the cylinder head (106, 406) reaches 90 ° C., whereby the first coolant circuit (109 ) Substantially stagnation of the cooling liquid in (202), and the temperature of the cooling liquid supplied from the second cooling liquid circuit (111) to the first cooling liquid circuit (109, 409) (T _in ) Is generated at least 10 ° C. lower than the temperature (T _out ) of the coolant discharged from the first coolant circuit (109, 409) to the second coolant circuit (111). The engine heat management method further comprises at least one of a step (205) for controlling the refrigerant pump (112). The step (205) of controlling the refrigerant pump (112) includes:
The temperature (T _in ) of the coolant supplied from the second coolant circuit (111) to the first coolant circuit (109, 409) is changed from the first coolant circuit (109, 409) to the second coolant circuit (109, 409). It is a step of controlling the refrigerant pump (112) so as to generate a refrigerant flow that is at least 20 ° C. lower than the temperature (T _out ) of the coolant discharged to the coolant circuit (111). The engine thermal management method according to claim 10. The step (205) of controlling the refrigerant pump (112) includes:
The temperature (T _in ) of the coolant supplied from the second coolant circuit (111) to the first coolant circuit (109, 409) is changed from the first coolant circuit (109, 409) to the second coolant circuit (109, 409). It is a step of controlling the refrigerant pump (112) so as to generate a refrigerant flow that is at least 30 ° C. lower than the temperature (T _out ) of the coolant discharged to the coolant circuit (111). The engine thermal management method according to claim 11.   Step (202) preventing the refrigerant pump (112) from pumping the coolant until the temperature of the coolant in the cylinder head (106, 406) reaches 100 ° C., or the refrigerant flow The engine thermal management method according to any one of claims 10 to 12, further comprising a step (205) of controlling the refrigerant pump (112) to generate the refrigerant pump (112).   Preventing the refrigerant pump (112) from pumping coolant until the temperature of the coolant in the cylinder head (106, 406) reaches 105 ° C, or generating the refrigerant stream The engine thermal management method according to claim 13, further comprising a step (205) of controlling the refrigerant pump (112).   Step (202) that prevents the refrigerant pump (112) from pumping coolant until the temperature of the coolant in the cylinder head (106, 406) reaches 110 ° C. The engine thermal management method according to claim 14, further comprising a step (205) of controlling the refrigerant pump (112) to generate the engine. A thermal management method for engines (101, 401),
The engine (101, 401)
An engine block (102, 402) having a coolant flow path (104, 404) therein;
A cylinder head (106, 406) fixed to the engine block (102, 402) and having a coolant flow path (108, 408) therein;
A first coolant circuit (109, 409) having each of the coolant channels (104, 108, 404, 408),
In the first coolant circuit (109, 409), a refrigerant flow is passed through the heat exchanger (412) for extracting heat from the coolant and warming the passenger compartment and the first coolant circuit (109, 409). A second coolant circuit (111) having a refrigerant pump (112) to be generated, a temperature detecting means (115), and a valve means (117) is connected,
The temperature (T _in ) of the coolant supplied from the second coolant circuit (111) to the first coolant circuit (109, 409) is changed from the first coolant circuit (109, 409) to the second coolant circuit (109, 409). A step (205) for controlling the refrigerant pump (112) so as to generate a refrigerant flow that is at least 10 ° C. lower than the temperature (T _out ) of the coolant discharged to the coolant circuit (111). An engine thermal management method. The step (205) of controlling the refrigerant pump (112) includes:
The temperature (T _in ) of the coolant supplied from the second coolant circuit (111) to the first coolant circuit (109, 409) is changed from the first coolant circuit (109, 409) to the second coolant circuit (109, 409). It is a step of controlling the refrigerant pump (112) so as to generate a refrigerant flow that is at least 20 ° C. lower than the temperature (T _out ) of the coolant discharged to the coolant circuit (111). The engine thermal management method according to claim 16. The step (205) of controlling the refrigerant pump (112) includes:
The temperature (T _in ) of the coolant supplied from the second coolant circuit (111) to the first coolant circuit (109, 409) is changed from the first coolant circuit (109, 409) to the second coolant circuit (109, 409). It is a step of controlling the refrigerant pump (112) so as to generate a refrigerant flow that is at least 30 ° C. lower than the temperature (T _out ) of the coolant discharged to the coolant circuit (111). The engine thermal management method according to claim 17.   A step of guiding the coolant discharged from the coolant channel (108, 408) of the cylinder head (106, 406) to the heat exchanger (412) for warming the passenger compartment. The engine thermal management method according to any one of claims 16 to 18.   20. The engine thermal management method according to any one of the preceding claims, further comprising the step of pumping coolant using a pump (112) that is drivably decoupled from the engine. An engine system equipped with engines (101, 401),
The engine (101, 401)
An engine block (102, 402) having a coolant flow path (104, 404) therein;
A cylinder head (106, 406) fixed to the engine block (102, 402) and having a coolant flow path (108, 408) therein;
A first coolant circuit (109, 409) having each of the coolant channels (104, 108, 404, 408),
The first coolant circuit (109, 409) is connected to the at least one heat exchanger (110, 116, 412) for extracting heat from the coolant and the refrigerant flow in the first coolant circuit (109, 409). A second coolant circuit (111) having a refrigerant pump (112), temperature detecting means (115) and valve means (117) for generating
21. An engine system comprising: at least one engine control unit (120) configured to perform the process according to any one of the preceding claims.

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