CN116006285A - An integrated thermal management system of an internal combustion engine and its control method - Google Patents

Abstract

The invention discloses an internal combustion engine integrated heat management system and a control method thereof, comprising an internal combustion engine and a waste heat recovery system, the waste heat recovery system comprising a working medium pump, a pressurized air preheater, a regenerator, and a jacket water preheater , flue gas heat exchanger, turbo expander, condenser and liquid storage tank; the integrated thermal management system of the internal combustion engine controls the first flow regulating valve, the three-way valve, the switch valve, the second flow regulating valve, the first The opening and opening and closing of the expansion regulating mechanism and the second expansion regulating mechanism realize the waste heat recovery of the internal combustion engine; the present invention controls the discharge of flue gas, cylinder jacket water and pressurized air from the internal combustion engine by setting valves and pumps on multiple branches. Waste heat utilization is compatible with waste heat recovery and thermal management of internal combustion engines.

Description

An integrated thermal management system of an internal combustion engine and its control method

technical field

The invention belongs to the technical field of waste heat recovery of internal combustion engines, and in particular relates to an integrated heat management system of an internal combustion engine coupled with a waste heat recovery system and a control method thereof.

Background technique

Internal combustion engines are widely used in industrial production and account for a very important proportion of energy consumption. Therefore, the energy saving and emission reduction of internal combustion engines is of great significance to achieve the double carbon target. However, more than 50% of the heat of the internal combustion engine is wasted in the environment by flue gas, cylinder jacket water, and pressurized air. Therefore, waste heat recovery technology is very important to improve the thermal efficiency of internal combustion engines. At the same time, the internal combustion engine also has relatively strict requirements on the temperature of the cylinder jacket water and the pressurized air, which requires a special internal combustion engine thermal management system. If the internal combustion engine thermal management system and the waste heat recovery system can be integrated into one system, not only can the waste heat be fully utilized to improve the efficiency of the internal combustion engine, but also the equipment redundancy of the internal combustion engine can be significantly reduced, and the practical application value of the waste heat recovery system can be improved.

CN110905619A discloses a mixed working medium Rankine cycle system utilizing internal combustion engine waste heat recovery. According to the characteristics of the mixed working medium, the system uses different heat sources of the internal combustion engine to recover waste heat in stages according to the energy quality. However, the above-mentioned system cannot take into account the thermal management function of the internal combustion engine, and cannot effectively control the temperature of the cylinder jacket water and charge air of the internal combustion engine under all working conditions, and an additional thermal management system needs to be added.

Contents of the invention

The purpose of the present invention is to overcome the deficiencies in the prior art, and propose an internal combustion engine integrated thermal management system coupled with a waste heat recovery system and its control method. The present invention integrates the internal combustion engine thermal management system and the waste heat recovery system into one system. Valves and pump elements are arranged on multiple branches, so as to realize the compatibility of waste heat utilization and thermal management of the flue gas discharged from the internal combustion engine, cylinder jacket water and charge air.

The first aspect of the present invention is to provide an integrated thermal management system for an internal combustion engine, which includes an internal combustion engine and a waste heat recovery system. devices, flue gas heat exchangers, turboexpanders, condensers and liquid storage tanks.

Wherein, the inlet of the working fluid pump is connected to the liquid storage tank, and the outlet of the working fluid pump is divided into two branches, one of which is connected to the cold fluid side inlet of the pressurized air preheater through a pipeline, and the other branch is connected to the cold fluid side inlet of the booster air preheater through a pipeline. The first flow regulating valve is connected to the cold fluid side inlet of the regenerator;

The charged air preheater includes a cold fluid side inlet, a cold fluid side outlet, a hot fluid side inlet and a hot fluid side outlet, and the charged air discharged from the internal combustion engine first flows into the hot fluid side of the charged air preheater through a pipeline The inlet and outlet on the hot fluid side are connected to the internal combustion engine; the outlet on the cold fluid side is divided into four branches: one branch is connected to the inlet of the second expansion regulating mechanism, and the outlet of the second expansion regulating mechanism merges with the working medium at the outlet of the turbo expander; Two branches are connected to the first port of the three-way valve, the second port of the three-way valve is connected to the inlet of the cold fluid side of the flue gas heat exchanger through a pipeline, and the third port of the three-way valve is connected to the inlet of the cold fluid side of the regenerator. The outlet is connected; the third branch is connected to the inlet of the second flow regulating valve, and the outlet of the second flow regulating valve merges with the outlet of the cold fluid side of the jacket water preheater; the fourth branch is connected to the inlet of the switch valve, and the switch The valve outlet is connected to the cold fluid side inlet of the jacket water preheater;

The jacket water preheater includes a cold fluid side inlet, a cold fluid side outlet, a hot fluid side inlet and a hot fluid side outlet. The jacket water discharged from the internal combustion engine first flows into the hot fluid side inlet of the jacket water preheater, and the cylinder The hot fluid side outlet of the jacket water preheater is connected to the internal combustion engine; the cold fluid side outlet of the jacket water preheater is divided into two branches: one branch is connected to the inlet of the first expansion adjustment mechanism, and the outlet of the first expansion adjustment mechanism The outlet merges with the working fluid at the outlet of the turboexpander; another branch connects the cold fluid side inlet of the flue gas heat exchanger;

The flue gas heat exchanger includes a cold fluid side inlet, a cold fluid side outlet, a hot fluid side inlet and a hot fluid side outlet. The flue gas discharged from the internal combustion engine first flows into the hot fluid side inlet of the flue gas heat exchanger, and then from the flue gas The hot fluid side outlet of the heat exchanger is discharged to the atmosphere; the cold fluid side outlet of the flue gas heat exchanger is connected to the inlet of the turbo expander;

The outlet of the turbo expander merges with the outlets of the first expansion regulating mechanism and the second expansion regulating mechanism respectively, and then connects with the hot fluid side inlet of the regenerator;

The hot fluid side outlet of the regenerator is connected with the hot fluid side inlet of the condenser, the hot fluid side outlet of the condenser is connected with the inlet of the liquid storage tank, and the outlet of the liquid storage tank is connected with the inlet of the working medium pump.

The working principle of the integrated thermal management system of the internal combustion engine is as follows: the working medium pump pressurizes the liquid cold working medium in the liquid storage tank, and then sends it to the pressurized air preheater and the pressurized air preheater and the In the regenerator; in the charge air preheater, the working fluid cools the heat source pressurized air to the required temperature range, and in the regenerator, the cold working medium absorbs the heat from the working medium after the turbo expander. A flow regulating valve is used to regulate the flow of the working medium from the working medium pump in the two branches. After the working fluid of the two branches (that is, the cold fluid outlet from the supercharged air preheater and the regenerator) converges, the jacket water preheater absorbs the heat of the jacket water discharged from the internal combustion engine to cool the jacket water to the temperature range required to enter the internal combustion engine. The cold working fluid from the jacket water preheater enters the flue gas heat exchanger to absorb the heat of the flue gas discharged from the internal combustion engine, and then becomes a high-temperature and high-pressure gas that expands in the turbo expander to perform work. The expanded working fluid releases heat in the regenerator to part of the liquid cold working fluid that flows in through the working fluid pump, and then enters the condenser to be recondensed into a liquid state and then stored in the liquid storage tank, and finally is used by the working fluid The mass pump pressurizes the delivery to start the next cycle.

Further, the integrated thermal management system of the internal combustion engine is realized by controlling the opening degree and opening and closing of the first flow regulating valve, the three-way valve, the switch valve, the second flow regulating valve, the first expansion regulating mechanism and the second expansion regulating mechanism Compatible with waste heat recovery and thermal management of internal combustion engines. Wherein: the first flow regulating valve is used to adjust the flow rate of the working medium in the branch circuit of the charge air preheater and the branch circuit of the regenerator; the three-way valve is used to control the flow direction of the working medium at the outlet of the cold fluid side of the regenerator ; The switch valve is used to open/close the working medium flow path of the cold fluid side inlet of the jacket water preheater; the second flow regulating valve is used to adjust the working medium flow on the branch; the first expansion adjustment The mechanism is used to control the flow of the working medium on the branch, thereby controlling the temperature of the cylinder jacket water after cooling; the second expansion regulating mechanism is used to control the flow of the working medium on the branch, thereby controlling the temperature of the supercharged air after cooling.

Further, the first and second expansion regulating mechanisms are expansion regulating valves or expanders.

The second aspect of the present invention is to propose a control method using the above-mentioned integrated thermal management system of the internal combustion engine, including:

When the internal combustion engine is in a hot engine state, that is, the temperature of the cooling water of the inner cylinder liner of the internal combustion engine is lower than 80-90°C, but the waste heat recovery system has been activated, the flow direction of the three-way valve is controlled according to the condition of the working fluid on the internal cooling side of the regenerator, Close the on-off valve, close the first expansion regulating mechanism, close the second expansion regulating mechanism, adjust the opening degree of the first flow regulating valve to distribute the optimal working fluid flow rate of the pressurized air preheater branch and the regenerator branch. The waste heat recovery system obtains the maximum output work and fully opens the second flow regulating valve; at this time, the working medium at the outlet of the cold fluid side of the charge air preheater and the working fluid at the outlet of the cold fluid side of the regenerator merge and pass through the second flow control valve. After the second flow regulating valve, it flows into the side inlet of the intercooler fluid of the flue gas heat exchanger;

When the internal combustion engine and the waste heat recovery system are working normally, control the flow direction of the three-way valve according to the condition of the working medium on the inner cold side of the regenerator; adjust the opening degree of the first flow regulating valve to distribute the charge air preheater branch and the heat recovery Open the on-off valve for the best working medium flow rate in the branch circuit of the device;

Judging the jacket water temperature at the hot fluid side outlet of the jacket water preheater:

If the jacket water temperature is lower than 80-90°C, reduce the flow of the working fluid pump and monitor the following parameters in real time: flow of the working fluid pump, flow of the cold fluid side inlet of the jacket water preheater, jacket water preheating The temperature at the hot fluid side outlet of the turbocharger, the charge air temperature at the hot fluid side outlet of the charge air preheater, and the working fluid temperature at the cold fluid side outlet of the flue gas heat exchanger, if any of the above parameter values exceeds the preset limit value, stop reducing the flow rate of the working fluid pump, open the second flow regulating valve and the second expansion regulating mechanism; control the working medium flow that finally enters the cold fluid side inlet of the flue gas heat exchanger and enters the jacket water preheater The flow rate of the working fluid at the inlet of the cold fluid side;

If the jacket water temperature is higher than about 95°C, increase the flow rate of the working fluid pump, and monitor the temperature and pressure of the working fluid at the outlet of the cold fluid of the flue gas heat exchanger in real time. When the pressure rises to the point where the working fluid can no longer evaporate in the jacket water preheater, while continuing to increase the flow rate of the working medium pump, open the first expansion regulating mechanism to control the inlet of the cold fluid that finally enters the flue gas heat exchanger The flow rate of the working medium; at this time, the second flow regulating valve and the second expansion regulating mechanism are completely closed.

Furthermore, when the internal combustion engine and the waste heat recovery system are working normally, if the temperature of the working fluid at the outlet of the cold fluid of the charge air preheater exceeds 40-50°C, increase the flow rate of the working fluid at the outlet of the working fluid pump, and monitor the following parameters in real time : The temperature of the jacket water at the outlet of the hot fluid side of the jacket water preheater is not lower than 80°C and the temperature of the working fluid at the outlet of the cold fluid side of the flue gas heat exchanger keeps the degree of superheat greater than 0, if any of the above two parameters If the limit value is exceeded, while continuing to increase the flow rate of the working medium pump, open the second expansion regulating mechanism to control the flow rate of the working medium entering the cold fluid side inlet of the jacket water preheater and the cold fluid side inlet of the flue gas heat exchanger, so that The above two parameters returned to within the limits.

Further, controlling the flow direction of the three-way valve according to the condition of the working medium on the inner cold side of the regenerator specifically includes:

Determine whether the working medium on the inner cold side of the regenerator has superheat, if so, close the first port of the three-way valve, otherwise close the second port of the three-way valve.

Furthermore, when the internal combustion engine is in a hot engine state, if the temperature of the working fluid at the outlet of the cold fluid of the charge air preheater exceeds 40-50°C, increase the flow rate of the working fluid at the outlet of the working fluid pump, and monitor the flue gas heat exchanger in real time The temperature of the working fluid at the outlet of the cold fluid side (keep the degree of superheat greater than 0). If the degree of superheat is lost, open the second expansion regulating mechanism to control the flow into the inlet of the cold fluid side of the flue gas heat exchanger, so that the degree of superheat can be restored to greater than 0 .

Compared with the prior art, the beneficial effects brought by the technical solution of the present invention are:

The integrated thermal management system of the internal combustion engine according to the present invention controls the waste heat utilization of the flue gas discharged by the internal combustion engine, cylinder jacket water and pressurized air by setting valves and pump elements on multiple branch roads, and realizes waste heat recovery and heat management of the internal combustion engine compatible;

Moreover, the present invention integrates the existing internal combustion engine thermal management system and the waste heat recovery system into one system. Compared with the traditional internal combustion engine waste heat recovery system, it not only makes full use of the waste heat to improve the efficiency of the internal combustion engine, but also significantly reduces the equipment redundancy of the internal combustion engine and improves the waste heat recovery. The practical application value of the recycling system.

Description of drawings

Fig. 1 is a structural schematic diagram of an integrated thermal management system for an internal combustion engine according to the present invention. in,

1: Working fluid pump 2: Charged air preheater 3: Regenerator

4: Jacket water preheater 5: Flue gas heat exchanger 6: Turbo expander

7: Condenser 8: Liquid storage tank 9: Internal combustion engine

10: First flow regulating valve 11: Three-way valve 12: On-off valve

13: Second flow regulating valve 14: First expansion regulating valve 15: Second expansion regulating valve

111: The first interface 112: The second interface 113: The third interface

Detailed ways

The technical solution of the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments, and the described specific embodiments are only for explaining the present invention, and are not intended to limit the present invention.

An integrated thermal management system for an internal combustion engine, comprising an internal combustion engine and a waste heat recovery system, the waste heat recovery system comprising a working fluid pump 1, a charge air preheater 2, a regenerator 3, a jacket water preheater 4, a flue gas Heat exchanger 5, turbo expander 6, condenser 7 and liquid storage tank 8.

The working principle of the integrated thermal management system of the internal combustion engine is as follows: the working medium pump 1 pressurizes the liquid cold working medium in the liquid storage tank 8, and then passes through the first flow regulating valve 10 and sends them to the pressurized air pre-heating system respectively through pipelines. In the heat exchanger 2 and the regenerator 3; in the charge air preheater 2, the working fluid cools the heat source pressurized air to the required temperature range, and in the regenerator 3, the refrigerant absorbs the refrigerant from the turbo expander 6 The heat of the working fluid, the first flow regulating valve 10 is used to adjust the flow of the working medium from the working medium pump 1 in the two branches. After the working fluids of the two branches (i.e. from the cold fluid outlets of the supercharged air preheater 2 and the regenerator 3) converge, the jacket water preheater 4 absorbs the heat of the jacket water discharged from the internal combustion engine 9, and the The jacket water is cooled to the temperature range required to enter the internal combustion engine. The refrigerant coming out of the jacket water preheater 4 enters the flue gas heat exchanger 5 to absorb the heat of the flue gas discharged from the internal combustion engine 9, and then becomes a high-temperature and high-pressure gas to expand in the turbo expander 6 to perform work. The expanded working fluid releases heat in the regenerator 3 to part of the liquid cold working fluid flowing in through the working medium pump 1, and then enters the condenser 7 to be recondensed into a liquid state and then stored in the liquid storage tank 8, and finally Pressurized by the working medium pump 1 to start the next cycle.

As shown in Figure 1, the technical scheme of the composition and component connection of the integrated thermal management system of the internal combustion engine is as follows:

The flue gas discharged from the internal combustion engine 9 is firstly connected with the hot fluid side inlet of the flue gas heat exchanger 5 as a heat source, and then flows out to the atmosphere from the hot fluid side outlet of the flue gas heat exchanger 5; The pressurized air formed after the pressurization of the compressor is first connected with the thermal fluid side inlet of the charge air preheater 2, and the thermal fluid side outlet of the charge air preheater 2 is connected with the intake port of the internal combustion engine; the cylinder exhausted by the internal combustion engine The jacket water is firstly connected to the thermal fluid side inlet of the jacket water preheater 4 , and the thermal fluid side outlet of the jacket water preheater 4 is connected to the internal combustion engine 9 .

The outlet of the working medium pump 1 is divided into two branches, one of which is connected to the cold fluid inlet of the charge air preheater 2 through a pipeline, and the other branch is first connected to the inlet of the first flow regulating valve 10, the second The outlet of a flow regulating valve 10 is connected to the cold fluid side inlet of the regenerator 3 . The cold fluid side outlet of the supercharged air preheater 2 is divided into four branches: one branch is connected to the inlet of the second expansion regulating valve 15, and the outlet of the second expansion regulating valve 15 is in phase with the working medium at the outlet of the turbo expander 6. confluence; the second branch is connected to the first interface of the three-way valve 11, the second interface of the three-way valve 11 is connected to the cold fluid side inlet of the flue gas heat exchanger 5 through a pipeline, and the third interface of the three-way valve 11 is connected to the The outlet on the cold fluid side of the regenerator 3 is connected; the third branch is connected to the inlet of the second flow regulating valve 13, and the outlet of the second flow regulating valve 13 merges with the cold fluid side outlet of the jacket water preheater 4; The fourth branch is connected to the inlet of the on-off valve 12 , and the outlet of the on-off valve 12 is connected to the cold fluid side inlet of the jacket water preheater 4 . The cold fluid side outlet of the jacket water preheater 4 is divided into two branches: one branch is connected to the inlet of the first expansion regulating valve 14, and the outlet of the first expansion regulating valve 14 is connected to the outlet of the turbo expander 6. The mass phases meet; another branch is connected to the cold fluid side inlet of the flue gas heat exchanger 5. Wherein, the cold fluid outlet of the flue gas heat exchanger 5 is connected to the inlet of the turbo expander 6, and the outlet of the turbo expander 6 is merged with the outlets of the first expansion regulating valve 14 and the second expansion regulating valve 15 respectively. , and then connected to the thermal fluid side inlet of the regenerator 3, the thermal fluid side outlet of the regenerator 3 is connected to the thermal fluid side inlet of the condenser 7, and the thermal fluid side outlet of the condenser 7 is connected to the inlet of the liquid storage tank 8 The outlet of the liquid storage tank 8 is connected with the inlet of the working fluid pump 1 . Wherein the first expansion regulating valve 14 can also be replaced by an expander.

The three-way valve 11 is used to control the flow direction of the working medium at the outlet of the cold fluid side of the regenerator 3, and the first interface of the three-way valve 11 is connected with the outlet of the cold fluid side of the charge air preheater 2 through a pipeline. The second port of the three-way valve 11 is connected to the inlet of the cold fluid side of the flue gas heat exchanger 5 through a pipeline, and the third port of the three-way valve 11 is connected to the outlet of the cold fluid side of the regenerator 3 . When the temperature of the working medium at the outlet of the turbo expander 6 is high, so that the working medium on the cold side of the regenerator 3 has superheated degree, the interface connecting the three-way valve 11 and the switch valve 12 is closed, and the regenerator 3 The cold fluid side outlet is connected with the cold fluid side inlet of the flue gas heat exchanger 5 through a three-way valve 11 . When the working medium on the cold side of the regenerator 3 does not reach the evaporation temperature or only a small amount of the working medium evaporates, close the second interface of the three-way valve, and at this time, the outlet of the cold fluid side of the regenerator 3 passes through the three-way valve 11 and the switch valve 12 The entrance is connected.

The on-off valve 12 is used to close the working medium flow path flowing into the inlet of the cold fluid side of the jacket water preheater 4 . When the cylinder jacket water temperature has not reached the required temperature range for the normal operation of the internal combustion engine, the on-off valve 12 is closed. The second flow regulating valve 13 is used to control the flow of the working medium on the branch, and when the on-off valve 12 is closed, the second flow regulating valve 13 is opened to allow the working medium to circulate and bypass the jacket water preheater 4 . The first expansion regulating valve 14 is used to control the flow rate of the working fluid on the branch, thereby controlling the temperature of the cylinder jacket water after cooling. The second expansion regulating valve 15 is used to control the flow rate of the working fluid on the branch, thereby controlling the temperature of the cooled supercharged air.

The control method using the above-mentioned integrated thermal management system of the internal combustion engine specifically includes:

The flue gas heat exchanger 5, charge air preheater 2, jacket water preheater 4 and regenerator 3 all have a cold fluid side inlet, a cold fluid side outlet, a hot fluid side inlet and a hot fluid side outlet , flow sensors, temperature sensors and pressure sensors are arranged at the outlet/inlet for monitoring the flow, temperature and pressure of the fluid passing through, and uploading the monitored values to the controller of the thermal management system for Control each valve and pump according to the monitored value. The specific control strategy includes:

When the internal combustion engine is in a hot engine state, that is, the temperature of the cooling water in the cylinder liner of the internal combustion engine is lower than the temperature required for the normal operation of the internal combustion engine, that is, in the range of about 80-90°C, but the waste heat recovery system has been activated, if the internal cooling of the regenerator 3 If the side working medium has superheat, close the first interface 111 of the three-way valve 11, otherwise close the second interface 112 of the three-way valve 11; then close the on-off valve 12, close the first expansion regulating valve 14, and close the second expansion regulating valve 15 , open the first flow regulating valve 10 to an appropriate opening adjustment to distribute the optimal working fluid flow of the charge air preheater 2 branch and the regenerator 3 branch so that the waste heat recovery system can obtain the maximum output work, fully open the first Two flow regulating valves 13. At this time, the working medium at the outlet of the cold fluid side of the charge air preheater 2 and the working medium at the outlet of the cold fluid side of the regenerator 3 merge, pass through the second flow regulating valve 13, and flow into the intercooler of the flue gas heat exchanger 5. The fluid side inlet; at the same time, in order to cool the supercharged air to the temperature required to enter the internal combustion engine, the flow rate of the working medium at the outlet of the working medium pump 1 can be increased. However, if the flow rate of the working medium is too large and the temperature of the working medium at the outlet of the cold fluid side of the flue gas heat exchanger 5 loses superheat, that is, when it cannot be completely evaporated, the second expansion regulating valve 15 is properly opened to control the flow into the flue gas heat exchanger 5 Flow at the cold fluid side inlet.

In the heat engine state, the working process of the waste heat recovery system includes: the working medium pump 1 pressurizes the liquid cold working medium in the liquid storage tank 8, and then transports the liquid cold working medium through the first flow regulating valve 10 to the pressurized air through the pipeline respectively. In the preheater 2 and regenerator 3; in the charge air preheater 2, the working fluid cools the charge air from the internal combustion engine to the required temperature range, and in the regenerator 3, the refrigerant absorbs the expansion from the turbine After the heat of the working fluid behind the engine 6, the working fluid from the outlet of the cold fluid side of the supercharged air preheater 2 and the regenerator 3 is combined, and the three-way valve 11 is controlled according to the condition of the working medium on the cold side of the regenerator 3 Flow direction, the cold working fluid flows into the side inlet of the flue gas heat exchanger 5 after passing through the second flow regulating valve 13 to absorb the heat from the flue gas of the internal combustion engine; The expanded working fluid releases heat in the regenerator 3 to the part of the liquid cold working fluid flowing in through the working fluid pump 1, then enters the condenser 7 and is recondensed into a liquid state and stored in the liquid storage tank 8, and finally It is then pressurized and transported by the working medium pump 1 to start the next cycle.

When the internal combustion engine and the waste heat recovery system are working normally, if the working medium on the inner cold side of the regenerator 3 has superheat (that is, a certain amount of evaporation occurs), then close the first interface 111 of the three-way valve 11, otherwise close the first interface 111 of the three-way valve 11 Two interface 112; adjust the first flow regulating valve 10 to an appropriate opening to distribute the optimal working fluid flow of the charge air preheater 2 branch and the regenerator 3 branch, open the switch valve 12; The working fluid in the heater 2 cools the charged air from the internal combustion engine to the required temperature range, and the cold working fluid in the regenerator 3 absorbs the heat from the working fluid after the turbo expander 6; from the charged air preheater 2 Converging with the working fluid at the outlet of the cold fluid side of the regenerator 3;

The other valves operate as follows:

1) If the temperature of the jacket water at the hot fluid side outlet of the jacket water preheater 4 is lower than 80°C, reduce the flow rate of the working medium pump 1 to reduce the flow rate of the cold fluid side inlet of the jacket water preheater 4, Furthermore, the temperature of the jacket water at the thermal fluid side outlet of the jacket water preheater 4 is increased; as the flow rate of the working medium pump 1 decreases, the temperature of the pressurized air at the thermal fluid side outlet of the boosted air preheater 2 will rise. High, the temperature of the working fluid at the outlet of the cold fluid side of the flue gas heat exchanger 5 will increase, the system pressure will decrease, and the utilization rate of waste heat and recovery heat of the flue gas will decrease; if any of the above five parameters changes to exceed preset limit value, stop reducing the flow rate of the working fluid pump 1, and at the same time open the second flow regulating valve 13 and the second expansion regulating valve 15 and adjust their openings to control the cold fluid that finally enters the flue gas heat exchanger 5 The flow rate of the working medium at the side inlet and the flow rate of the working medium entering the side inlet of the cold fluid of the jacket water preheater 4, so as to control the above parameters within the range of the limit value.

2) If the temperature of the jacket water at the hot fluid side outlet of the jacket water preheater 4 is higher than about 95°C, increase the flow rate of the working fluid pump 1 to increase the flow rate of the cold fluid side inlet of the jacket water preheater 4 , and then reduce the jacket water temperature at the outlet of the hot fluid side of the jacket water preheater 4 . As the flow rate of the working medium pump 1 increases, the temperature of the working medium at the outlet of the cold fluid side of the flue gas heat exchanger 5 will decrease or even fail to evaporate completely, and the pressure of the working medium at the outlet of the cold fluid of the flue gas heat exchanger 5 will increase , these will seriously affect the performance of the system, and the temperature and pressure of the working fluid at the outlet of the cold fluid of the flue gas heat exchanger 5 must be limited within a certain range. Therefore, when the flow rate of the working medium pump 1 is increased to the point that the temperature of the working medium loses its superheat, or the pressure of the working medium increases to the point that the working medium cannot evaporate in the jacket water preheater 4, continue to increase the working medium pump At the same time, the first expansion regulating valve 14 is opened to control the flow rate of the working medium that finally enters the inlet of the cold fluid side of the flue gas heat exchanger 5, thereby increasing the temperature and temperature of the working medium at the outlet of the cold fluid side of the flue gas heat exchanger 5. Reduce the working fluid pressure here. At this time, the second flow regulating valve 13 and the second expansion regulating valve 15 are completely closed.

3) When the internal combustion engine and the waste heat recovery system are working, if the temperature of the working medium at the outlet of the cold fluid of the charge air preheater 2 exceeds 40°C, increase the flow rate of the working medium at the outlet of the working medium pump 1; but if the flow rate of the working medium is too large , will cause the temperature of the jacket water at the outlet of the hot fluid side of the jacket water preheater 4 to be too low, and the temperature of the working fluid at the outlet of the cold fluid side of the flue gas heat exchanger 5 to be too low or even unable to completely evaporate. The above two parameters are monitored in real time. If the jacket water temperature is lower than 80°C or the superheat of the working fluid is greater than 0, the second expansion must be turned on while continuing to increase the working fluid flow rate of the working fluid pump 1. Regulate the valve 15 and adjust the opening to control the flow of working fluid entering the cold fluid side inlet of the jacket water preheater 4 and the cold fluid side inlet of the flue gas heat exchanger 5, so that the above two parameters return to the limit range.

Although the preferred embodiments of the present invention have been described above in conjunction with the accompanying drawings, the present invention is not limited to the above-mentioned specific embodiments. The above-mentioned specific embodiments are only illustrative and not restrictive. Those of ordinary skill in the art Under the enlightenment of the present invention, people can also make many forms without departing from the purpose of the present invention and the scope of protection of the claims, and these all belong to the protection scope of the present invention.

Claims (6)

1. An integrated thermal management system for an internal combustion engine, comprising an internal combustion engine (9) and a waste heat recovery system, the waste heat recovery system comprising a working fluid pump (1), a charge air preheater (2), and a heat regenerator (3) , jacket water preheater (4), flue gas heat exchanger (5), turbo expander (6), condenser (7) and liquid storage tank (8); Wherein, the inlet of the working fluid pump (1) is connected to the liquid storage tank (8), and the outlet of the working fluid pump (1) is divided into two branches, one of which passes through the pipeline and the pressurized air preheater (2) The cold fluid side inlet is connected, and the other branch is connected to the cold fluid side inlet of the regenerator (3) through the first flow regulating valve (10); The supercharged air preheater (2) includes a cold fluid side inlet, a cold fluid side outlet, a hot fluid side inlet and a hot fluid side outlet, and the supercharged air discharged from the internal combustion engine first flows into the supercharged air preheater ( 2) The hot fluid side inlet and the hot fluid side outlet are connected to the internal combustion engine; the cold fluid side outlet is divided into four branches: one branch is connected to the inlet of the second expansion regulating mechanism (15), and the outlet of the second expansion regulating mechanism (15) is connected to the The working medium at the outlet of the turbo expander (6) is combined; the second branch is connected to the first port of the three-way valve (11), and the second port of the three-way valve (11) is connected to the flue gas heat exchanger through the pipeline. (5) is connected to the inlet of the cold fluid side, and the third interface of the three-way valve (11) is connected to the outlet of the cold fluid side of the regenerator (3); the third branch is connected to the inlet of the second flow regulating valve (13), The outlet of the second flow regulating valve (13) merges with the cold fluid side outlet of the jacket water preheater (4); the fourth branch is connected to the inlet of the on-off valve (12), and the outlet of the on-off valve (12) is connected to the cylinder jacket The cold fluid side inlet of the water preheater (4); The jacket water preheater (4) includes a cold fluid side inlet, a cold fluid side outlet, a hot fluid side inlet and a hot fluid side outlet, and the jacket water discharged from the internal combustion engine first flows into the jacket water preheater (4). The hot fluid side inlet and the hot fluid side outlet of the jacket water preheater (4) are connected to the internal combustion engine 9; the cold fluid side outlet of the jacket water preheater (4) is divided into two branches: one branch is connected to the first The inlet of an expansion regulating mechanism (14), the outlet of the first expansion regulating mechanism (14) merges with the working medium at the outlet of the turbo expander (6); the other branch connects the cooling of the flue gas heat exchanger (5) Fluid side inlet; the flue gas heat exchanger (5) includes a cold fluid side inlet, a cold fluid side outlet, a hot fluid side inlet and a hot fluid side outlet, and the flue gas discharged from the internal combustion engine (9) first flows into the flue gas heat exchanger The hot fluid side inlet of (5) is then discharged to the atmosphere from the hot fluid side outlet of the flue gas heat exchanger (5); the cold fluid side outlet of the flue gas heat exchanger (5) is connected with the turbo expander (6) connected to the entrance; The outlet of the turboexpander (6) merges with the outlets of the first expansion regulating mechanism (14) and the second expansion regulating mechanism (15) respectively, and then connects with the thermal fluid side inlet of the regenerator (3); The hot fluid side outlet of the regenerator (3) is connected with the hot fluid side inlet of the condenser (7), the hot fluid side outlet of the condenser (7) is connected with the inlet of the liquid storage tank (8), and the liquid storage tank ( 8) The outlet is connected with the inlet of the working fluid pump (1). 2. The internal combustion engine integrated thermal management system according to claim 1, characterized in that, the internal combustion engine integrated thermal management system controls the first flow regulating valve (10), the three-way valve (11), the switching valve (12 ), the opening and closing of the second flow regulating valve (13), the first expansion regulating mechanism (14) and the second expansion regulating mechanism (15) realize the compatibility of waste heat recovery and heat management of the internal combustion engine; The first flow regulating valve (10) is used to regulate the flow rate of the working medium in the branch circuit of the charge air preheater (2) and the branch circuit of the regenerator (3); The three-way valve (11) is used to control the flow direction of the working medium at the outlet of the cold fluid side of the regenerator (3); The switch valve (12) is used for opening/closing the working medium flow path of the cold fluid side inlet of the jacket water preheater (4); The second flow regulating valve (13) is used to regulate the flow of working fluid on the branch where it is located; The first expansion regulating mechanism (14) is used to control the flow rate of the working medium on the branch, thereby controlling the temperature of the cylinder jacket water after cooling; The second expansion regulating mechanism (15) is used to control the flow rate of the working fluid on the branch, so as to control the temperature of the supercharged air after cooling. 3. The control method of the internal combustion engine integrated thermal management system according to claim 1, comprising: When the internal combustion engine is in a hot engine state, that is, the temperature of the cooling water in the cylinder liner of the internal combustion engine is lower than 80-90°C, but the waste heat recovery system has been started, the three-way valve is controlled according to the working fluid on the internal cooling side of the regenerator (3) (11), close the switch valve (12), close the first expansion regulating mechanism (14), close the second expansion regulating mechanism (15), adjust the opening degree of the first flow regulating valve (10) to distribute the pressurized air The optimal working fluid flow rate of the preheater (2) branch and the regenerator (3) branch makes the waste heat recovery system obtain the maximum output work, and the second flow regulating valve (13) is fully opened; After the working fluid at the outlet of the cold fluid side of the heater (2) and the outlet of the cold fluid side of the regenerator (3) are combined, they flow into the flue gas heat exchanger (5) after passing through the second flow regulating valve (13) Intercooler fluid side inlet; When the internal combustion engine and the waste heat recovery system are working normally, control the flow direction of the three-way valve (11) according to the working fluid on the inner cooling side of the regenerator (3); adjust the opening of the first flow regulating valve (10) to distribute the boost Open the on-off valve (12) for the optimal working fluid flow rate of the air preheater (2) branch and the regenerator (3) branch; Judging the jacket water temperature at the hot fluid side outlet of the jacket water preheater (4): If the jacket water temperature is lower than 80-90°C, reduce the flow rate of the working fluid pump (1), and monitor the following parameters in real time: the flow rate of the working fluid pump (1), the cold fluid side of the jacket water preheater (4) The flow rate of the inlet, the temperature at the hot fluid side outlet of the jacket water preheater (4), the charge air temperature at the hot fluid side outlet of the charge air preheater (2), and the flue gas heat exchanger (5) cooling If the temperature of the working medium at the outlet of the fluid side exceeds the preset limit value, stop reducing the flow of the working medium pump (1), open the second flow regulating valve (13) and the second expansion regulating mechanism ( 15); control the flow of working fluid that finally enters the cold fluid side inlet of the flue gas heat exchanger (5) and the working fluid flow that enters the cylinder jacket water preheater (4) cold fluid side inlet; If the jacket water temperature is higher than 95°C, increase the flow rate of the working fluid pump (1), and monitor the temperature and pressure of the working fluid at the cold fluid outlet of the flue gas heat exchanger (5) in real time. heat, or when the working fluid pressure rises to the point where the working fluid can no longer evaporate in the jacket water preheater (4), while continuing to increase the flow rate of the working fluid pump (1), open the first expansion regulating mechanism (14) , to control the flow rate of the working medium that finally enters the cold fluid side inlet of the flue gas heat exchanger (5); at this time, the second flow regulating valve (13) and the second expansion regulating mechanism (15) are completely closed. 4. The control method according to claim 3, characterized in that, when the internal combustion engine and the waste heat recovery system are working normally, if the temperature of the working medium at the outlet of the cold fluid of the charge air preheater (2) exceeds 40-50°C , increase the flow rate of the working medium at the outlet of the working medium pump (1), and monitor the following parameters in real time: the temperature of the jacket water at the outlet of the hot fluid side of the jacket water preheater (4) is not lower than 80°C and the flue gas heat exchange The temperature of the working medium at the outlet of the cold fluid side of the device (5) keeps the degree of superheat greater than 0. If any of the above two parameters exceeds its limit value, while continuing to increase the flow rate of the working medium pump (1), turn on the second expansion regulator The mechanism (15) controls the flow rate of working fluid entering the cold fluid side inlet of the jacket water preheater (4) and the cold fluid side inlet of the flue gas heat exchanger (5), so that the above two parameters return to the limit value range. 5. The control method according to claim 3, characterized in that controlling the flow direction of the three-way valve (11) according to the condition of the working fluid on the inner cooling side of the regenerator (3) specifically includes: Determine whether the working fluid on the inner cold side of the regenerator (3) has superheat, if so, close the first interface (111) of the three-way valve (11), otherwise close the second interface (112) of the three-way valve (11). 6. The control method according to claim 3, characterized in that, when the internal combustion engine is in a hot state, if the temperature of the working medium at the outlet of the cold fluid of the charge air preheater (2) exceeds 40-50°C, increase the working temperature. The flow rate of the working medium at the outlet of the mass pump (1), and the temperature of the working medium at the outlet of the cold fluid side of the flue gas heat exchanger (5) is monitored in real time, and the degree of superheat is kept greater than 0. If When the degree of superheat is lost, the second expansion regulating mechanism 15 is opened to control the flow of the cold fluid side inlet of the flue gas heat exchanger 5, Return superheat to greater than 0.

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