Supercharged engine exhaust energy comprehensive utilization system based on thermoelectric device and utilization method thereof
Technical Field
The invention relates to an engine, in particular to an engine exhaust energy utilization system.
Background
The internal combustion engine is one of the main power devices due to the characteristics of high thermal efficiency, small weight and size, simple and convenient operation and maintenance and the like. The internal combustion engine is used as a main form of power output, the efficiency of the internal combustion engine is not more than 45% at most, most energy is dissipated in the form of heat energy, and the energy dissipated in the form of tail gas accounts for about 35% of the total energy. If the high-grade tail gas energy with high specific gravity can be effectively utilized, the fuel consumption can be reduced, the effective output power of the engine can be improved, and the method has important significance for realizing energy conservation and emission reduction of the internal combustion engine. Therefore, a method for improving the fuel utilization efficiency of an internal combustion engine by recycling the exhaust gas waste heat is increasingly gaining attention.
Disclosure of Invention
The invention aims to provide a thermoelectric equipment-based supercharged engine exhaust energy comprehensive utilization system and a thermoelectric equipment-based supercharged engine exhaust energy comprehensive utilization method for realizing recovery of exhaust waste heat of an engine under different working conditions.
The purpose of the invention is realized as follows:
the invention relates to a supercharged engine exhaust energy comprehensive utilization system based on thermoelectric equipment, which is characterized in that: the internal combustion engine air inlet passage is connected with the air compressor and the atmosphere in a three-way mode, the internal combustion engine exhaust passage is connected with the turbine air inlet three-way pipeline and the internal combustion engine natural exhaust three-way pipeline in a three-way mode, a turbine bypass valve is arranged between the turbine air inlet three-way pipeline and the internal combustion engine natural exhaust three-way pipeline, the heat exchanger air inlet three-way pipeline behind the turbine, the internal combustion engine natural exhaust three-way pipeline and the heat exchanger gas phase air inlet channel are connected in a three-way mode, the heat exchanger liquid phase inlet is connected with the outlet of the energy storage pool, the heat exchanger liquid phase outlet is connected with the inlet of.
The supercharged engine exhaust energy comprehensive utilization system based on the thermoelectric device can further comprise:
1. the air inlet channel, the air compressor and the atmosphere tee joint of the internal combustion engine are provided with an air inlet channel tee joint valve, the exhaust channel, the turbine air inlet tee joint pipeline and the natural exhaust tee joint pipeline of the internal combustion engine are provided with an exhaust channel tee joint valve, the air inlet channel tee joint valve and the exhaust channel tee joint valve are ball valves, and the turbine bypass valve is a butterfly valve.
2. The energy storage pool is of a water storage tank structure, and the internal working medium is paraffin oil.
The invention relates to a method for comprehensively utilizing the exhaust energy of a supercharged engine based on thermoelectric equipment, which is characterized by comprising the following steps of: the air inlet three-way valve, the air outlet three-way valve and the turbine bypass valve are connected with the control unit;
(1) the internal combustion engine is in a low working condition, the exhaust of the internal combustion engine is insufficient to drive the turbocharger to pressurize air, the air inlet of the air inlet three-way valve connected with the air compressor is closed through the control unit, and the air inlet three-way valve and the air inlet of the atmosphere are opened to form a natural air suction channel of the internal combustion engine; closing an exhaust port of the exhaust passage three-way valve connected with a turbine air inlet three-way pipeline, opening the exhaust port connected with a natural exhaust three-way pipeline of the internal combustion engine to form a natural exhaust passage, and closing a turbine bypass valve; the waste gas is discharged from an exhaust pipe, enters a natural exhaust three-way pipeline of the internal combustion engine through an exhaust passage three-way valve, finally enters a gas phase flow path of a heat exchanger from a gas inlet three-way pipeline of the heat exchanger, and exchanges heat with a liquid phase flow path, fluid which exchanges heat enters an energy storage pool under the action of a working medium pump, meanwhile, liquid in the energy storage pool enters the heat exchanger through the suction action of the working medium pump to complete the circulation of the working medium, and the energy storage pool transmits heat to thermoelectric equipment attached to the energy storage pool, so that the thermoelectric equipment generates electricity and enters an energy storage unit through the transmission of a;
(2) the internal combustion engine is in a high working condition, exhaust of the internal combustion engine can drive the turbocharger to pressurize air, an air inlet connected with an air compressor through an air inlet three-way valve is opened through a control unit, the air inlet of the air inlet three-way valve and the air is closed, high-pressure air enters an internal combustion engine cylinder through the air inlet three-way valve, an exhaust port connected with a turbine air inlet three-way valve through an exhaust passage three-way valve is opened, an exhaust port connected with a natural exhaust three-way pipe of the internal combustion engine is closed, and the opening of a turbine bypass valve is controlled to prevent the rotating speed of the turbine from exceeding the maximum speed through comparison of; after being discharged from an exhaust pipe, tail gas enters a turbine through an exhaust passage three-way valve to do work on the turbine so as to drive a gas compressor to rotate through a turbine shaft, meanwhile, a turbine bypass valve is partially opened, part of the tail gas enters a natural exhaust three-way pipeline of an internal combustion engine through the exhaust three-way valve, finally, the tail gas and the tail gas discharged by the turbine are gathered in a gas inlet three-way pipeline of a heat exchanger and enter a gas phase flow path of the heat exchanger, heat exchange is carried out between the tail gas and the liquid phase flow path, fluid subjected to heat exchange enters an energy storage pool under the action of a working medium pump, meanwhile, liquid in the energy storage pool enters the heat exchanger through the suction action of the working medium pump to complete the circulation of the working medium, and the energy storage pool.
The method for comprehensively utilizing the exhaust energy of the supercharged engine based on the thermoelectric device can further comprise the following steps of:
1. the method comprises the steps of identifying the output power of the internal combustion engine, judging whether the output power is greater than a set value or not, if the output power is less than the set value, judging whether a system is in a low working condition or not, detecting an air inlet three-way valve and an air outlet three-way valve to judge open channels of the air inlet three-way valve and the air outlet three-way valve, switching the two valve channels through a control unit, enabling the two valve channels to open the two channels respectively, simultaneously checking whether a turbine bypass valve is completely closed or not, and if the turbine bypass valve is; if the set value is larger than or equal to the set value, the system is judged to be in a high working condition, whether the three-way valve of the air inlet channel and the three-way valve of the exhaust channel respectively open the supercharging air inlet channel and the exhaust turbine channel is detected, the channels opened by the two valves are controlled by the control unit, the two channels on the two valves are opened, the opening degree of the turbine bypass valve is detected, the opening degree of the turbine bypass valve is compared with preset parameters of the control unit under the same working condition, if the two valves are equal, the controller of the turbine bypass valve does not work, and if not.
The invention has the advantages that:
1. the invention can utilize the layout of the pipeline and the control of the valve, and finally convert the heat energy in the tail gas of the internal combustion engine into the electric energy for storage through the heat exchanger, the energy storage pool, the thermoelectric equipment and other devices, thereby realizing the aim of recovering the waste heat of the tail gas.
2. The invention can have two working modes of high working condition and low working condition, has wide operating power range, can recover and store energy with different qualities, and has good adaptability.
3. The system has the advantages of small structure size, light weight and strong adaptability, can be applied to vehicles such as automobiles and ships, and can meet the power generation requirement of a power plant.
4. The thermoelectric equipment selected by the invention has the characteristics of wide application range, light weight and the like, and the application of the thermoelectric equipment as an energy recovery device can not only improve the efficiency, but also effectively reduce the use area and make the system more compact.
Drawings
FIG. 1 is a schematic structural view of the present invention;
FIG. 2 is a valve control flow diagram of the present invention.
Detailed Description
The invention will now be described in more detail by way of example with reference to the accompanying drawings in which:
with reference to fig. 1-2, the supercharged engine exhaust energy comprehensive utilization system based on thermoelectric equipment of the present invention is composed of an internal combustion engine 1, an intake passage three-way valve 2, a compressor 3, a turbine shaft 4, an exhaust passage three-way valve 5, a turbine intake three-way pipeline 6, a turbine 7, a heat exchanger intake three-way pipeline 8, an energy storage unit 9, an energy storage pool 10, thermoelectric equipment 11, a working medium pump 12, a heat exchanger 13, an internal combustion engine natural exhaust three-way pipeline 14, a turbine bypass valve 15, a control unit 16, pipelines, etc., and has the specific structure that:
1. the air inlet three-way valve 5 is provided with two air inlets and an air outlet, the air outlet is directly connected with an air inlet of the internal combustion engine 1, one of the air inlets is connected with the outlet of the air compressor 3, and the air compressor 3 is connected with the turbine 7 through the turbine shaft 4; the exhaust passage three-way valve 5 is provided with two exhaust ports and one air inlet, the air inlet is connected with an exhaust pipe of the internal combustion engine 1, the two exhaust ports are respectively connected with a turbine air inlet three-way pipeline 6 and a branch pipe of a natural exhaust three-way pipeline 14 of the internal combustion engine, the other branch pipe of the two three-way pipelines is connected with two ends of a turbine bypass valve 15, the last branch of the turbine air inlet three-way pipeline 6 is connected with an inlet of a turbine 7, and an outlet of the turbine 7 and one branch pipe of the natural exhaust three-way pipeline 14 of the internal combustion engine are connected with two branch pipes;
2. the heat exchanger 13 has a gas-liquid two-phase flow path in common, a gas phase inlet of the heat exchanger is connected with a branch of a heat exchanger gas inlet three-way pipeline 8, a liquid phase inlet of the heat exchanger is connected with an outlet of the energy storage pool 10 through a pipeline, a liquid phase outlet of the heat exchanger is connected with an inlet of the energy storage pool 10 through a working medium pump 12, the thermoelectric device 11 is attached to the outer wall of the energy storage pool 10 and is connected with the energy storage unit 9 through a lead, and the control unit 16 is connected with each valve.
The energy storage pool 10 is a small water storage tank with an outlet and an inlet, and the working medium in the energy storage pool is paraffin oil with high flash point, high boiling point and high specific heat capacity.
Exhaust passage three-way valve 5, intake duct three-way valve 2 are ball valves, turbine bypass valve 15 be the butterfly valve, the three all is connected with control unit 16 and is controlled by it, intake duct three-way valve 2 can realize two air inlets between flow switch with the gas vent form a flow path, exhaust passage three-way valve 5 can realize two gas vents between flow switch with the air inlet form a flow path, turbine bypass valve 15 can carry out the control of valve aperture.
The periphery of the pipelines is wrapped with heat insulation materials to prevent heat dissipation, and the pipelines are connected only by bolts.
The control is that the control unit 16 controls the exhaust passage three-way valve 5, the intake passage three-way valve 2 and the turbine bypass valve 15 to realize the control of the gas flow path through identifying the working condition, and finally, the energy is recovered and stored through the heat exchanger 13, the energy storage pool 10, the thermoelectric device 11, the energy storage unit 9 and the like, and the specific implementation mode is as follows:
1. the internal combustion engine 1 is in a low working condition, the exhaust of the internal combustion engine 1 is insufficient to drive the turbocharger to pressurize air, an air inlet of the air inlet passage three-way valve 2 connected with the air compressor is closed through the control unit 16, and the other air inlet is opened to form a natural air suction channel of the internal combustion engine 1 to enable the internal combustion engine to naturally suck air; an exhaust port of the exhaust passage three-way valve 5 connected with the turbine air inlet three-way pipeline 6 is closed, and an exhaust port connected with the internal combustion engine natural exhaust three-way pipeline 14 is opened to form natural exhaust; the turbine bypass valve 15 is fully closed. The internal combustion engine naturally inhales air through the air inlet three-way valve 2, after air participates in combustion and does work in a cylinder, waste gas is discharged from an exhaust pipe, enters the internal combustion engine natural exhaust three-way pipe 14 through the exhaust pipe three-way valve 5, finally enters a gas phase flow path of the heat exchanger 13 from the heat exchanger air inlet three-way pipe 8 to exchange heat with a liquid phase flow path, fluid which exchanges heat enters the energy storage pool 10 under the action of the working medium pump 12, meanwhile, liquid in the energy storage pool 10 enters the heat exchanger 13 through the suction action of the working medium pump 12 to complete working medium circulation, the energy storage pool 10 with higher temperature transmits heat to the thermoelectric equipment 11 attached to the energy storage pool, and the thermoelectric equipment generates electricity and enters the energy storage unit 9 through the transmission of a lead.
2. The internal combustion engine 1 is in a high working condition, exhaust of the internal combustion engine 1 can drive a turbocharger to pressurize air, an air inlet connected with an air compressor through an air inlet three-way valve 2 is opened through a control unit 16, high-pressure air enters an internal combustion engine cylinder through the air inlet three-way valve 2 by closing the other air inlet, an exhaust port connected with a turbine air inlet three-way valve 6 through an exhaust three-way valve 5 is opened, an exhaust port connected with a natural exhaust three-way pipe 14 of the internal combustion engine is closed, high-quality tail gas enters a turbine 7, and meanwhile, the opening degree of a turbine bypass valve 15 is controlled by comparing preset parameters in a control system with the working condition to prevent the turbine from rotating too fast. High-pressure air from a compressor 3 enters a cylinder of an internal combustion engine 1 through an air inlet three-way valve 2, combustion work is performed in the cylinder, generated tail gas is discharged from an exhaust pipe, enters a turbine 7 through an exhaust three-way valve 5 to perform work on the turbine so as to drive the compressor to rotate through a turbine shaft, meanwhile, a turbine bypass valve 15 is opened at a certain angle, a part of tail gas enters a natural exhaust three-way pipeline 14 of the internal combustion engine through the turbine bypass valve, finally, the tail gas discharged by the turbine 7 is converged in a heat exchanger air inlet three-way pipeline 8 and enters a gas phase flow path of a heat exchanger 13 to perform heat exchange with a liquid phase flow path, fluid subjected to heat exchange enters an energy storage pool under the action of a working medium pump 12, meanwhile, liquid in the energy storage pool 10 enters the heat exchanger through the suction action of the working medium pump 12 to complete the circulation of the working medium, and, so that the generated electricity is transmitted into the energy storage unit 16 through the lead and stored therein.
The working condition identification and the specific control flow of the valve are as follows: as shown in fig. 2, firstly, the output power of the internal combustion engine is identified, and then whether the output power is greater than a set value is judged, if the output power is less than the set value, the system is judged to be in a low working condition, the inlet three-way valve 2 and the outlet three-way valve 5 are detected to judge the channels opened by the inlet three-way valve and the outlet three-way valve, if the natural suction channel and the natural exhaust channel are respectively opened, the system does not operate, otherwise, the two valve channels are switched through the control unit through the analysis of the control system, so that the two channels are respectively opened, and simultaneously, whether the turbine bypass valve 15 is completely closed is checked, if the system is completely closed; (ii) a If the pressure of the air inlet channel three-way valve 2 and the exhaust channel three-way valve 5 is smaller than the set value, the system is judged to be in a high working condition, whether the pressure boosting air inlet channel and the exhaust turbine channel are respectively opened or not is detected, if the pressure boosting air inlet channel and the exhaust turbine channel are opened, the two valve controllers are not operated, otherwise, the channels opened by the two valves are controlled through the controller after the analysis of the control system, the two channels on the two valves are opened, meanwhile, the system can detect the opening degree of the turbine bypass valve 15 and compare the opening degree with preset parameters in the system under the same working condition, if the pressure boosting air inlet channel and the exhaust turbine channel are equal, the controller does not work, and otherwise, the controller adjusts the.