CN205400924U - System for it rates to improve EGR engine energy utilization - Google Patents

Abstract

The utility model discloses a system for it rates to improve EGR engine energy utilization, power transmission system includes the engine, the engine combustion gas is partly through exhaust turbine turbocharging system, second grade heat exchanger and exhaust after treatment system, another part process exhaust gas recirculation system, the engine cooling system still heats the assembly with the driver's cabin when going on handling to the cooling water of engine and is connected, signal acquisition system accepts the temperature that temperature sensor gathered to give data analysis execution systems, end circulation system with engine cooling water, engine exhaust and waste gas again the heat energy among the circulation system regard as the heat source, carry out multistage heating to the cycle fluid, inflation acting in the inflation ware afterwards, the drive is generated electricity with the coaxial generator of ware that expands to store the electric energy that sends in the battery, accomplish the conversion of heat energy to the chemical energy. Utilizing fuel combustion to emit but not being converted into that partly chemical energy of mechanical energy by the engine through end circulation furthest.

Description

A System for Improving Energy Utilization Efficiency of EGR Engine

technical field

The utility model relates to the technical field of internal combustion engines, in particular to a system for improving the energy utilization rate of an EGR engine.

Background technique

Exhaust Gas Recirculation (EGR) refers to the technology that the engine separates a part of the exhaust gas and introduces it into the intake side to make it burn again. The Rankine cycle refers to an ideal cycle process using water vapor as a working medium, which mainly includes isentropic compression, isobaric heating, isentropic expansion, and an isobaric condensation process.

As we all know, only about 30% of the energy produced by the combustion of common engine fuel can be converted into mechanical work, and the effective efficiency of the most advanced diesel engine is no more than 45%, but most of the energy is still taken away by high-temperature exhaust gas and cooling water, and discharged to into the atmosphere, resulting in energy loss. From the perspective of energy quality, the exhaust temperature of a diesel engine can reach 600°C, and the exhaust temperature of a gasoline engine can reach 700°C. The exhaust energy in the engine still has a relatively high quality. Therefore, recovering this part of energy through the Rankine cycle has become a way to realize energy saving of vehicles, improve the effective energy utilization rate of vehicles and reduce carbon emissions.

At present, most of the methods to improve energy utilization are to simply install a heat exchanger behind the exhaust pipe, which brings about the problem that if the size of the heat exchanger is too small, the circulating working medium of the Rankine cycle cannot fully absorb heat , reaching an overheated state; if the size of the heat exchanger is too large, it will lead to an increase in the exhaust back pressure of the engine, increase the load on the engine, and reduce the thermal efficiency of the engine. Moreover, in an engine equipped with an exhaust gas recirculation system (EGR) system, it is often necessary to add an intercooler between the exhaust pipe and the compressor to reduce the temperature of the exhaust gas, and this part of the energy is wasted in vain. Therefore, it is necessary to make reasonable and full use of the exhaust gas energy of the engine.

Utility model content

The purpose of this utility model is to solve the above problems and provide a system for improving the energy utilization rate of the EGR engine. When the engine is working normally, the system uses the bottom cycle to maximize the use of fuel combustion released but is not converted by the engine. The part of chemical energy that is mechanical energy.

In order to achieve the above object, the utility model adopts the following technical solutions:

A system for improving the energy utilization rate of an EGR engine, including a power transmission system, the power transmission system includes an engine; part of the exhaust gas discharged from the engine is discharged through an exhaust gas turbocharging system, a secondary heat exchanger and an exhaust after-treatment system The other part goes through the exhaust gas recirculation system and then enters the engine with fresh air for a new cycle; the engine cooling system processes the cooling water of the engine and is also connected to the cab heating assembly; the signal acquisition system accepts temperature sensor acquisition temperature and send it to the data analysis execution system for processing;

The bottom circulation system uses the heat energy in the engine cooling water, engine exhaust and exhaust gas recirculation system as the heat source to heat the circulating working fluid in multiple stages to make it fully absorb heat, and then expands in the expander to do work, driving the same process as the expander. The shaft generator generates electricity and stores the generated electric energy in the battery to complete the conversion of heat energy into chemical energy.

The power transmission system also includes a gearbox, a retarder and a drive axle sequentially connected to the engine through a transmission shaft.

The bottom circulation system includes a drive pump, a primary heat exchanger, a secondary heat exchanger, a tertiary heat exchanger, an expander and a condenser connected sequentially through pipelines; the expander and the generator are connected through a transmission shaft connect.

A bottom cycle initial temperature sensor is installed on the connecting pipeline between the drive pump and the primary heat exchanger; a bottom cycle final temperature sensor is installed on the connecting pipeline between the third stage heat exchanger and the expander, and all The temperature sensors are all connected to the data acquisition system, and the data acquisition system is connected to the data analysis execution system; the data analysis execution system is electrically connected to the driving pump switch.

The exhaust gas turbocharging system includes an exhaust gas turbocharger, the compressor intake end of the exhaust gas turbocharger is connected to the intake pipe through an air pipeline, and the air outlet end is connected to the supercharged intercooler and the engine through an air pipeline. Gas manifolds are connected sequentially;

The turbine intake end of the exhaust gas turbocharger is connected to the engine exhaust manifold through an air pipeline, and the gas outlet is connected to the engine aftertreatment system and the secondary heat exchanger of the bottom circulation system through an air pipeline.

The exhaust gas of the exhaust gas recirculation system comes from the exhaust manifold of the engine, and then passes through the air pipeline through the three-stage heat exchanger of the bottom circulation system, and enters the intake end of the exhaust gas turbocharger compressor.

The engine cooling system includes a cooling water tank, a cooling water pump, an engine, a cab heating assembly, a primary heat exchanger of a bottom circulation system, and an engine radiator that are sequentially connected in circulation through a cooling water pipeline.

A cooling water temperature sensor is provided on the connecting pipeline between the engine and the cab heating assembly; a cab temperature sensor is provided on the cab heating assembly; the cab heating assembly and the bottom circulation system There are primary cooling water temperature sensors on the connection pipeline between them, and all the temperature sensors are connected with the data acquisition system, and the data acquisition system is connected with the data analysis execution system; the data analysis execution system is connected with the cab heating assembly The three-way solenoid valve is connected with the three-way solenoid valve of the primary heat exchanger.

The beneficial effects of the utility model:

The utility model utilizes the bottom cycle based on the Rankine cycle, so that the circulating working fluid flows through three heat exchangers to absorb heat, and finally reaches the state of superheated steam, expands in the expander to do work, drives the generator to generate electricity, and realizes the conversion of heat energy into electricity and store it in batteries.

The utility model can also heat the driver's cab according to the driver's intention, directly make the cooling water and the driver's cab air perform forced heat exchange, increase the temperature of the driver's cab, reduce the use of the air conditioner, and avoid the air conditioner's impact on the environment to a certain extent. destruction.

The utility model has a simple structure, and the existing vehicle can be realized by simply refitting without affecting the performance of the original vehicle, which can improve energy utilization rate and promote energy saving and emission reduction.

Description of drawings

Accompanying drawing 1 is utility model system circulation and structural schematic diagram.

Accompanying drawing 2 is the flow chart of the control strategy of the utility model system cycle.

Among them, 1 engine, 2 gearbox, 3 cooling water temperature sensor, 4 retarder, 5 drive axle, 6 three-way solenoid valve, 7 cab heating assembly, 8 cab temperature sensor, 9 secondary heat exchanger, 10 primary cooling water temperature sensor, 11 primary heat exchanger, 12 engine after-treatment system, 13 bottom cycle initial temperature sensor, 14 drive pump, 15 data analysis execution system, 16 data acquisition system, 17 condenser, 18 tertiary exchange Heater, 19 generator, 20 expander, 21 engine radiator, 22 bottom cycle final temperature sensor, 23 cooling water tank, 24 exhaust gas turbocharger, 25 intercooler, 26 cooling water pump.

detailed description

detailed description

Below in conjunction with accompanying drawing and embodiment the utility model is further described.

A system for improving the energy utilization rate of an EGR engine includes: a power transmission system, an exhaust gas turbocharger system, an exhaust gas recirculation system, an exhaust system, an engine cooling system, a bottom circulation system, and a signal acquisition and processing execution system.

The power transmission system includes an engine 1 , a gearbox 2 , a retarder 4 and a drive axle 5 sequentially connected through a transmission shaft.

The exhaust gas turbocharging system includes that the compressor intake end of the exhaust gas turbocharger 24 is connected with the intake pipe through the air pipeline, and the outlet end is connected with the supercharged intercooler 25 and the intake manifold of the engine 1 through the air pipeline in sequence. Connection; the turbine intake end of the exhaust gas turbocharger 24 is connected with the exhaust manifold of the engine 1 through an air pipeline, and the outlet end is connected with the engine aftertreatment system 12 of the engine 1 and the bottom cycle secondary heat exchanger 9 through an air pipe road connection;

The exhaust gas of the exhaust gas recirculation system comes from the exhaust manifold of the engine 1, passes through the air pipeline, passes through the bottom cycle three-stage heat exchanger 18, and enters the intake end of the exhaust gas turbocharger 24 compressor;

The engine cooling system includes a cooling water tank 23, a cooling water pump 26, an engine 1, a cab heating assembly 7, a bottom cycle primary heat exchanger 11, an engine radiator 21, etc., which are sequentially circulated through the cooling water pipeline; A cooling water temperature sensor 3 is provided on the connecting pipeline between the cab heating assemblies 7; a cab temperature sensor 8 is provided on the cab heating assembly 7; A primary cooling water temperature sensor 10 is provided on the connecting pipeline between them;

The bottoming cycle system includes a driving pump 14, a bottoming cycle primary heat exchanger 11, a bottoming cycle secondary heat exchanger 9, a bottoming cycle tertiary heat exchanger 18, an expander 20, a condenser 17, etc. ; The connection pipeline between the drive pump 14 and the primary heat exchanger 11 is provided with a bottom circulation initial temperature sensor 13; the connection pipeline between the three-stage heat exchanger 18 and the expander 20 is provided with a bottom circulation Final temperature sensor 22; the expander 20 is connected with the high-speed generator 19 through a transmission shaft;

The cooling water temperature sensor 3 collects the real-time temperature of the cooling water flowing out from the engine; the cab temperature sensor 8 collects the temperature of the cab; the primary cooling water temperature sensor 10 collects the temperature after the cab heating assembly 7 and before the primary heat exchanger 11 Water temperature; the bottom cycle initial temperature sensor 13 collects the temperature of the circulating medium pumped out by the drive pump 14; the bottom cycle final temperature sensor 22 collects the final temperature of the circulating medium after the three-stage heat exchange 18;

The cooling water temperature sensor 3, the cab temperature sensor 8, the primary cooling water temperature sensor 10, the bottom cycle initial temperature sensor 13, and the bottom cycle final temperature sensor 22 are all connected to the data acquisition system 16; the data acquisition system 16 is connected to the data analysis execution system 15 connection; the data analysis execution system 15 is connected with the bottom cycle drive pump 14 switch, the three-way solenoid valve 6 of the cab heating assembly 7 and the three-way solenoid valve of the bottom cycle primary heat exchanger 11;

During the working process of the engine 1 , the cooling water pump 26 transports the cooling water from the cooling water tank 23 to the engine 1 , enters the heat dissipation link after exchanging heat with the body, and finally returns to the cooling water tank 23 to enter the next cycle. The exhaust gas of the engine 1 is divided into two parts, one part enters the exhaust gas turbocharger 24, and expands in the turbine to perform work (this part of work is used to drive the compressor to compress the mixture of fresh air and EGR exhaust gas that is about to enter the engine), and then through the exhaust gas. The gas aftertreatment system and the secondary heat exchanger 9 enter the atmosphere.

In the bottom cycle, the circulating working fluid flows under the action of the driving pump 14, absorbs heat in the three heat exchangers and finally forms superheated steam, and the superheated steam expands in the high-speed expander 20 to do work, driving the turbine to rotate, and finally the remaining exhaust The gas releases heat through the condenser 17 to form an unsaturated liquid and enters the next cycle. During this process, the rotation of the turbine drives the generator to generate electricity, which is stored in the battery. The system is used to collect heat energy that would otherwise be wasted in this cycle and convert it into usable electrical energy.

Under the condition of normal operation of the engine, the utility model utilizes the part of the chemical energy released by fuel combustion but not converted into mechanical energy by the engine to the greatest extent through the bottom cycle. The bottoming cycle uses engine cooling water, engine exhaust and heat energy in the exhaust gas recirculation system (EGR) as heat sources to heat the circulating working fluid in multiple stages to make it fully absorb heat, and then expands in the expander to do work, driving and The generator coaxial with the expander generates electricity and stores the generated electric energy in the battery to complete the conversion of thermal energy into chemical energy. In addition, the system and method can also realize the function of heating the cab in cold weather.

A control method for improving the energy utilization rate of an EGR engine, comprising the following steps:

S201: When the bottom cycle is in progress, the initial temperature sensor located at the outlet of the driving pump and the primary cooling water temperature sensor located in front of the primary heat exchanger respectively transmit the temperature of the working medium and cooling water to the Data analysis execution system;

S202: The data analysis execution system compares these two temperatures; if the difference exceeds 10% (it can be set artificially, and is not limited to 10% here), the data analysis execution system compares the two temperatures of the first-stage heat exchanger Pass the solenoid valve to issue an instruction, and the solenoid valve is in the unobstructed state of the heat exchanger; otherwise, the heat exchange will not be performed in the primary heat exchanger, and the next step S203 will be directly skipped and S204 will be performed;

S203: The circulating working fluid exchanges heat with the cooling water in the primary heat exchanger;

S204: The circulating working fluid performs heat exchange in the secondary and tertiary heat exchangers, and the circulating working medium absorbs heat;

S205: Determine whether the temperature of the working medium is greater than the saturation temperature: if yes, it means that the working medium has reached saturation or supersaturation; if otherwise, it means that the working medium does not absorb enough heat, and the current working condition is not suitable for bottom cycle, and the system pauses for 5 minutes (It can be set artificially, not limited to the 5 minutes here), and then re-execute S201;

S206: The circulating working fluid does work on the expander and releases heat in the condenser;

S207: Determine whether there is a shutdown request, if yes, the cycle ends; if not, go to S201 for a new cycle.

When the vehicle is driving in cold weather, the driver can choose to turn on the vehicle heating system according to his own needs. At this time, the temperature sensor located at the engine cooling water outlet and the temperature sensor in the cab will respectively pass the data of the cooling water temperature and the temperature in the cab. The acquisition system passes it to the data analysis execution system. If the cooling water temperature is ten degrees higher than the temperature of the cab (it can be set artificially, not limited to ten degrees here), the data analysis execution system will send the three-way solenoid valve of the cab heating assembly and the cab cooling fan When an instruction is issued, the solenoid valve switches to the state of the radiator, and the fan is turned on. At this time, the cooling water flows through the radiator, and the forced heat exchange is performed under the action of the radiator fan to increase the temperature in the cab. Otherwise, the solenoid valve is in the flow pipe state, the fan is turned off, and the engine is used to directly drive the air conditioner for heating.

Although the specific implementation of the utility model has been described above in conjunction with the accompanying drawings, it does not limit the protection scope of the utility model. Those skilled in the art should understand that on the basis of the technical solution of the utility model, those skilled in the art do not need to Various modifications or deformations that can be made with creative efforts are still within the protection scope of the present utility model.

Claims (8)

1. improving a system for EGR engine energy utilization rate, it is characterized in that, including power drive system, described power drive system includes electromotor；Row is to air after exhaust turbocharging system, secondary heat exchanger and exhaust after treatment system for the waste gas part that described electromotor is discharged, and another part enters electromotor with fresh air after gas recirculation system and carries out new circulation；Engine-cooling system also heats assembly with driver's cabin while the cooling water of electromotor is processed and is connected；Signal acquiring system accept temperature sensor gather temperature, and give data analysis perform system process；

Bottom cycle system is using the heat energy in engine cooling water, engine exhaust and gas recirculation system as thermal source, cycle fluid is carried out Multi-stage heating, so as to fully absorb heat, expansion work in expansion apparatus subsequently, the electromotor coaxial with expansion apparatus is driven to generate electricity, and the electrical power storage sent in accumulator, complete heat energy to chemistry transformation of energy.

2. a kind of system improving EGR engine energy utilization rate as claimed in claim 1, is characterized in that, described power drive system also includes the change speed gear box, retarder and the drive axle that are sequentially connected with electromotor by power transmission shaft.

3. a kind of system improving EGR engine energy utilization rate as claimed in claim 1, is characterized in that, described bottom cycle system includes being circulated successively the driving pump of connection, first-class heat exchanger, secondary heat exchanger, three grades of heat exchangers, expansion apparatus and condenser by pipeline；Described expansion apparatus is connected by power transmission shaft with electromotor.

4. a kind of system improving EGR engine energy utilization rate as claimed in claim 3, is characterized in that, the connecting line between described driving pump and first-class heat exchanger is provided with bottoming cycle just temperature sensor；Described three grades of connecting lines between heat exchanger and expansion apparatus are provided with bottoming cycle final temperature sensor, and all of temperature sensor is all connected with described data collecting system, and data collecting system performs system with described data analysis and is connected；Data analysis performs system and electrically connects with driving switch pump.

5. a kind of system improving EGR engine energy utilization rate as claimed in claim 1, it is characterized in that, described exhaust turbocharging system includes exhaust-driven turbo-charger exhaust-gas turbo charger, the compressor air inlet machine end of exhaust-driven turbo-charger exhaust-gas turbo charger is connected with air inlet pipe by air pipe line, and outlet side is sequentially connected with intercooler and motor intake manifold by air pipe line；

The turbine inlet end of exhaust-driven turbo-charger exhaust-gas turbo charger is connected by air pipe line with enmgine exhaust, and outlet side is connected by air pipe line with the secondary heat exchanger of engine aftertreatment system and bottom cycle system.

6. a kind of system improving EGR engine energy utilization rate as claimed in claim 5, it is characterized in that, the waste gas of described gas recirculation system, from enmgine exhaust, then passes through the air pipe line three grades of heat exchangers through bottom cycle system, enters the inlet end of exhaust-driven turbo-charger exhaust-gas turbo charger compressor.

7. a kind of system improving EGR engine energy utilization rate as claimed in claim 1, it is characterized in that, described engine-cooling system includes being circulated successively the cooling water tank of connection by cooling water pipeline, cooling water pump, electromotor, driver's cabin heat assembly, the first-class heat exchanger of bottom cycle system and engine radiator.

8. a kind of system improving EGR engine energy utilization rate as claimed in claim 7, is characterized in that, the connecting line that described electromotor and driver's cabin heat between assembly is provided with coolant temperature sensor；Described driver's cabin heats assembly and is provided with cabin temperature sensor；Described driver's cabin heats the connecting line between assembly and bottom cycle system and is provided with one-level coolant temperature sensor, and all of temperature sensor is all connected with data collecting system, and described data collecting system performs system with data analysis and is connected；Described data analysis performs the three-way magnetic valve of three-way magnetic valve and first-class heat exchanger that system heats assembly with driver's cabin and is connected.