Engine exhaust temperature control device

Abstract

The utility model discloses an engine exhaust temperature control device, which is used for model selection of a three-way catalyst of a power assembly rack and comprises a gas mixing control unit, a temperature control unit and a temperature control unit, the adjusting valve is arranged between the first pipeline and the second pipeline; the exhaust cooling unit comprises an air inlet, an air outlet, a first air channel and a second air channel, the first air channel and the second air channel are arranged in parallel and are both communicated with the first pipeline, a switch valve and a first cooler are arranged on the first air channel in a penetrating mode, a second cooler is arranged on the second air channel in a penetrating mode, and the first cooler is communicated with the second cooler. The first cooling loop and the second cooling loop are both connected with the radiator. According to the engine exhaust gas temperature control device, the temperature adjusting range is enlarged, the temperature adjusting accuracy is improved, the cooling capacity of the engine exhaust gas temperature control device is improved, and condensate water is prevented from being generated.

Description

Technical Field

[0001] The utility model relates to the technical field of vehicle manufacturing, in particular to an engine exhaust temperature control device. Background Art

[0002] The relevant technology points out that the powertrain bench three-way catalytic converter test is used to solve the catalyst selection work in the early stage of vehicle development and improve the development efficiency of the selection work. The performance of the catalyst is closely related to its gas inlet temperature. At present, the catalyst selection test items mainly include ignition temperature characteristic test, air-fuel ratio characteristic test, and oxygen storage capacity test. All three require the exhaust temperature to be stabilized at a fixed temperature point. Among them, the ignition temperature characteristic test requires the exhaust gas inlet temperature entering the three-way catalytic converter to be controlled at 200℃~450℃, and the temperature step length is adjustable by 20℃. The air-fuel ratio characteristic test requires the catalyst inlet temperature to be measured at 450℃±10℃.

[0003] For the hybrid engine test bench, the exhaust temperature is above 400°C under steady-state low-load conditions. If the air-fuel ratio is adjusted under test conditions, the exhaust temperature will shift, making it difficult to ensure consistent test temperature conditions. In order to achieve the conversion performance of the catalyst at different temperatures, the temperature must be stabilized at an extremely low exhaust temperature of around 200°C. At this time, external cooling equipment is required to adjust the exhaust temperature, and the temperature regulation accuracy is low, and the temperature control ability is poor. Utility Model Content

[0004] The utility model aims to solve at least one of the technical problems existing in the prior art. To this end, the utility model provides an engine exhaust temperature control device, which can increase the temperature adjustment range and improve the accuracy of temperature adjustment.

[0005] According to the engine exhaust temperature control device of the utility model, the engine exhaust temperature control device is used for the selection of a three-way catalytic converter on a powertrain bench, and the engine exhaust temperature control device includes: a gas mixing control unit, the gas mixing control unit includes a regulating valve; an exhaust pipeline unit, the exhaust pipeline unit includes a first pipeline and a second pipeline, and the regulating valve is arranged between the first pipeline and the second pipeline; an exhaust cooling unit, the exhaust cooling unit is arranged on the first pipeline, the exhaust cooling unit includes: an air inlet, an air outlet, a first air path and a second air path, the first air path and the second air path are arranged in parallel, the first air path is connected to the first pipeline through the air inlet and the air outlet, the second air path is connected to the first pipeline through the air inlet and the air outlet, a switch valve and a first cooler are arranged on the first air path, a second cooler is arranged on the second air path, and the first cooler is connected in series to the first cooling circuit, the second cooler is connected in series to the second cooling circuit, the first cooling circuit and the second cooling circuit are arranged in parallel and are both connected to a radiator.

[0006] According to the engine exhaust temperature control device of the utility model, by setting two gas circuits and two parallel cooling circuits, the temperature adjustment range is increased, the accuracy of temperature adjustment is improved, the cooling capacity of the engine exhaust temperature control device is improved, the generation of condensed water is avoided, and the efficiency and accuracy of verification and selection are improved.

[0007] In some embodiments, the exhaust cooling unit further includes: a first thermostat and a second thermostat, the first thermostat being disposed in the first cooling circuit, and the second thermostat being disposed in the second cooling circuit.

[0008] In some embodiments, the exhaust cooling unit further includes: a first water pump and a second water pump, the first water pump is disposed in the first cooling circuit, and the second water pump is disposed in the second cooling circuit.

[0009] In some embodiments, the exhaust cooling unit further includes: a cooling fan, wherein the cooling fan is arranged close to the radiator and is used to cool the radiator.

[0010] In some embodiments, the exhaust cooling unit further includes: a pressure sensor and a first temperature sensor, both of which are disposed on the second gas path, and the pressure sensor is configured to monitor the gas path pressure and determine whether the exhaust cooling unit is operating normally.

[0011] In some embodiments, the exhaust pipe unit further includes: a transfer flange, the transfer flange is connected between the first pipe and the engine, and two ends of the second pipe are respectively connected to the transfer flange and the regulating valve.

[0012] In some embodiments, the second pipeline is arranged in parallel with the exhaust cooling unit.

[0013] In some embodiments, the exhaust pipe unit further includes: a third pipe, wherein a three-way catalytic converter is passed through the third pipe, and exhaust direct sampling test pieces are provided at both ends of the three-way catalytic converter.

[0014] In some embodiments, the gas mixing control unit further includes: a second temperature sensor, which is disposed upstream of the three-way catalytic converter in the airflow direction and between the exhaust direct sampling detection component and the three-way catalytic converter.

[0015] In some embodiments, the engine exhaust temperature control device further includes: a measurement and control unit, which is electrically connected to the gas mixing control unit, the exhaust pipe unit and the exhaust cooling unit.

[0016] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a schematic diagram of an engine exhaust temperature control device according to an embodiment of the utility model;

[0018] Figure 2 yes Figure 1 Schematic diagram of the exhaust cooling unit shown in .

[0019] Reference numerals:

[0020] 100. Engine exhaust temperature control device; 1. Adapter flange; 2. First pipeline; 3. Exhaust cooling unit; 4. Third pipeline; 5. Regulating valve; 6. Second pipeline; 7. Emission direct sampling measurement point; 8. Second temperature sensor; 9. Three-way catalytic converter; 31. Air inlet; 32. Air outlet; 33. First air path; 34. Second air path; 35. Switch valve; 36. First cooler; 37. Second cooler; 38. Radiator; 39. First thermostat; 310. Second thermostat; 311. First water pump; 312. Second water pump; 313. Cooling fan; 314. Pressure sensor; 315. First temperature sensor; 316. First cooling circuit; 317. Second cooling circuit; 200. Engine. DETAILED DESCRIPTION

[0021] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0022] Reference below Figure 1 and Figure 2 An engine exhaust temperature control device 100 according to an embodiment of the present invention is described.

[0023] like Figure 1 and Figure 2 As shown, the engine exhaust temperature control device 100 according to the embodiment of the utility model includes: a gas mixing control unit, an exhaust pipe unit and an exhaust cooling unit 3.

[0024] Specifically, the engine exhaust temperature control device 100 is used for selecting the three-way catalytic converter 9 of the powertrain bench. The gas mixing control unit includes a regulating valve 5. The exhaust pipeline unit includes a first pipeline 2 and a second pipeline 6. The regulating valve 5 is arranged between the first pipeline 2 and the second pipeline 6. The exhaust cooling unit 3 is arranged on the first pipeline 2. The exhaust cooling unit 3 includes: an air inlet 31, an air outlet 32, a first air path 33 and a second air path 34. The first air path 33 and the second air path 34 are arranged in parallel. The first air path 33 The first gas circuit 33 is connected to the first pipeline 2 through the air inlet 31 and the air outlet 32, the second gas circuit 34 is connected to the first pipeline 2 through the air inlet 31 and the air outlet 32, the first gas circuit 33 is provided with a switch valve 35 and a first cooler 36, the second gas circuit 34 is provided with a second cooler 37, and the first cooler 36 is connected in series to the first cooling circuit 316, the second cooler 37 is connected in series to the second cooling circuit 317, the first cooling circuit 316 and the second cooling circuit 317 are arranged in parallel and are both connected to the radiator 38. Therefore, the engine exhaust temperature control device 100 has a simple structure and a clever design.

[0025] According to the engine exhaust temperature control device 100 of the embodiment of the utility model, by setting two gas circuits and two parallel cooling circuits, the temperature adjustment range is increased, the accuracy of temperature adjustment is improved, the cooling capacity of the engine exhaust temperature control device 100 is improved, the generation of condensed water is avoided, and the efficiency and accuracy of verification and selection are improved.

[0026] As shown in the figure, the first cooling circuit 316 and the second cooling circuit 317 are arranged in parallel, and the first cooling circuit 316 and the second cooling circuit 317 are both connected to the radiator 38, the first cooling circuit 316 is connected in series with the first cooler 36, the first gas path 33 is arranged in the first cooler 36, the second cooling circuit 317 is connected in series with the second cooler 37, the second gas path 34 is arranged in the second cooler 37, the two ends of the first gas path 33 are connected to the air inlet 31 and the air outlet 32 ​​respectively, the two ends of the second gas path 34 are connected to the air inlet 31 and the air outlet 32 ​​respectively, and the first gas path 33 is connected in series with the switch valve 35 for controlling the on and off of the first gas path 33. Further, the switch valve 35 is an electric switch valve, when the switch valve 35 is opened, the first gas path 33 and the second gas path 34 are both opened; when the switch valve 35 is closed, the first gas path 33 is closed, and only the second gas path 34 is opened. Specifically, when the exhaust gas temperature reaches the target temperature, the on-off valve 35 is opened to open the first gas path 33, thereby increasing the gas cooling amount and cooling efficiency.

[0027] Preferably, both the first cooler 36 and the second cooler 37 are EGR coolers (Exhaust Gas Recirculation Coolers).

[0028] In some embodiments of the present invention, Figure 2 As shown, the exhaust cooling unit 3 further includes: a first thermostat 39 and a second thermostat 310, wherein the first thermostat 39 is disposed in the first cooling circuit 316, and the second thermostat 310 is disposed in the second cooling circuit 317. Specifically, the first thermostat 39 opens the full cooling capacity when the refrigerant temperature in the first cooling circuit 316 reaches above 50°C, and the second thermostat 310 opens the full cooling capacity when the refrigerant temperature in the second cooling circuit 317 reaches above 50°C. Thus, the cooling efficiency is improved, the flexibility and reliability of the exhaust cooling unit 3 are increased, and the waste of resources and the generation of condensed water caused by overcooling are avoided.

[0029] In some embodiments of the present invention, Figure 2 As shown, the exhaust cooling unit 3 also includes: a first water pump 311 and a second water pump 312, the first water pump 311 is connected to the first cooling circuit 316, and the second water pump 312 is connected to the second cooling circuit 317. Specifically, the first water pump 311 and the second water pump 312 are both EGR coolant circulation water pumps, and the coolant flow rate is adjusted by controlling the speed of the water pump through the PWM wave (pulse width modulation) method. As a result, the two water pumps operate independently, so that the exhaust cooling unit 3 can adapt to different working conditions more flexibly, ensuring the reliability of the engine exhaust temperature control device 100.

[0030] In some embodiments of the present invention, Figure 2As shown, the exhaust cooling unit 3 further includes: a cooling fan 313, which is arranged close to the radiator 38 and is used to cool the radiator 38. Specifically, the radiator 38 has a pressure relief valve and an expansion kettle, which ensures the stable operation of the first cooling circuit 316 and the second cooling circuit 317, and reduces the failure rate of the exhaust cooling unit 3.

[0031] In some embodiments of the present invention, Figure 2 As shown, the exhaust cooling unit 3 further includes: a pressure sensor 314 and a first temperature sensor 315, both of which are arranged on the second gas path 34, and the pressure sensor 314 is configured to monitor the gas path pressure and determine whether the exhaust cooling unit 3 is working normally. Specifically, by monitoring the pressure of the pressure sensor 314, it is diagnosed whether the exhaust cooling unit 3 stops working, whether the valve body is stuck, and whether the pressure is normal during normal operation, thereby ensuring that the exhaust cooling unit 3 can operate safely and efficiently.

[0032] In some embodiments of the present invention, Figure 1 As shown, the exhaust pipe unit further includes: an adapter flange 1, which is connected between the first pipe 2 and the engine 200, and the two ends of the second pipe 6 are respectively connected to the adapter flange 1 and the regulating valve 5. Specifically, the regulating valve 5 is a pneumatic three-way proportional regulating valve, which is used to dynamically adjust the exhaust cooling flow. As a result, the overall structure of the engine exhaust temperature control device 100 is simplified, the cooling efficiency is improved, and it is easy to assemble and maintain.

[0033] In some embodiments of the utility model, the second pipeline 6 is arranged in parallel with the exhaust cooling unit 3. Specifically, a part of the exhaust gas enters the first pipeline 2 through the adapter flange 1 and enters the exhaust cooling unit 3 for cooling, and the other part of the exhaust gas enters the second pipeline 6 through the adapter flange 1, and both are connected to the regulating valve 5. The two parts of gas are mixed at the regulating valve 5 to reach a certain temperature. In this way, while ensuring that the gas temperature is not too high, it avoids waste of resources, reduces cooling power, and is stable and reliable.

[0034] In some embodiments of the utility model, the exhaust pipe unit further includes: a third pipe 4, the third pipe 4 is penetrated by a three-way catalytic converter 9, and emission direct sampling measuring pieces are provided at both ends of the three-way catalytic converter 9. Thus, the pollutant concentration is measured before the exhaust gas enters the three-way catalytic converter 9, and the exhaust gas after the conversion is completed in the three-way catalytic converter 9 is measured again, so as to realize the real-time monitoring of the emission control effect.

[0035] In some embodiments of the utility model, the gas mixing control unit further includes: a second temperature sensor 8, which is disposed upstream of the three-way catalytic converter 9 in the airflow direction and between the exhaust direct sampling test piece and the three-way catalytic converter 9. Thus, by real-time monitoring of the gas temperature, the engine exhaust temperature control device 100 can adjust the strategy in a timely manner, protect the three-way catalytic converter 9, ensure the use state of the three-way catalytic converter 9, and extend the life of the three-way catalytic converter 9.

[0036] In some embodiments of the present invention, the engine exhaust temperature control device 100 further includes: a measurement and control unit, which is electrically connected to the gas mixing control unit, the exhaust pipe unit, and the exhaust cooling unit 3. Thus, the provision of the measurement and control unit realizes accurate control and comprehensive management of the exhaust temperature of the engine 200, improves the performance and durability of the engine 200, and significantly reduces emissions.

[0037] Optionally, the measurement and control unit may be a PLC (Programmable Logic Controller), a secondary instrument with a feedback adjustment function, or the like.

[0038] The following will refer to Figure 1-Figure 2 An engine exhaust temperature control device 100 according to a specific embodiment of the present invention is described.

[0039] The exhaust end of the engine 200 is connected to the adapter flange 1, the adapter flange 1 is connected to the first pipeline 2, and the adapter flange 1 is also connected to the second pipeline 6. A part of the exhaust gas flows out from the first pipeline 2 through the exhaust cooling unit 3 and flows to the pneumatic three-way proportional control valve 5, and the other part of the exhaust gas flows through the second pipeline 6 to the pneumatic three-way proportional control valve 5 and then mixed. The temperature of the mixed gas is reduced, and the pollutant concentration of the original exhaust gas emitted by the engine 200 is measured at the emission direct sampling measurement point 7. The temperature of the mixed gas is measured by the second temperature sensor 8 to complete the temperature closed-loop control. After the gas passes through the three-way catalytic converter 9 to complete the conversion of each pollutant, it flows through the next emission direct sampling measurement point 7 to complete the measurement of the pollutant concentration after conversion.

[0040] Specifically, the exhaust gas cooling unit 3 includes a first gas path 33 , a second gas path 34 , a first cooling circuit 316 and a second cooling circuit 317 . The flow mode of the gas in the first gas path 33 is as follows: the exhaust gas enters the pipeline from the air inlet 31, passes through the electric switch valve 35 and flows into the first cooler 36, and the cooled exhaust gas is discharged from the air outlet 32; the flow mode of the gas in the second gas path 34 is as follows: the exhaust gas enters the pipeline from the air inlet 31 and flows into the second cooler 37, and the cooled exhaust gas passes through the pressure sensor 314 and the first temperature sensor 315 and is discharged from the air outlet 32; the flow mode of the refrigerant in the first cooling circuit 316 is as follows: it flows into the first cooling circuit 316 from the radiator 38, exchanges heat with the gas in the first gas path 33 at the first cooler 36, flows to the first thermostat 39, passes through the first water pump 311 and flows into the radiator 38 for cooling; the flow mode of the refrigerant in the second cooling circuit 317 is as follows: it flows into the second cooling circuit 317 from the radiator 38, exchanges heat with the gas in the second gas path 34 at the second cooler 37, flows to the second thermostat 310, passes through the second water pump 312 and flows into the radiator 38 for cooling.

[0041] The working process of the engine exhaust temperature control device 100 is described below:

[0042] Pretreatment: In the heat stage, the engine 200 is operated to the working point, the pneumatic three-way proportional control valve 5 is in the fully open position, the electric switch valve 35 is opened, and the cooling outlet temperature of the first gas path 33 is monitored to be higher than 50°C, and the operating point temperature adjustment and maintenance stage begins.

[0043] Steady-state temperature maintenance working condition: set the exhaust target temperature to 200°C, open the electric switch valve 35, adjust the engine 200 to the working load point, place the pneumatic three-way proportional control valve 5 in the middle position, use the measurement and control unit PWM wave control to adjust the speed of the first water pump 311 and / or the second water pump 312, keep the second temperature sensor 8 at about ±20°C of the target temperature, send a 4mA-20mA current signal to adjust the opening of the pneumatic three-way proportional control valve 5, and distribute the gas flow to further accurately control the temperature to the target temperature ±2°C. When operating at a high temperature above 400°C, close the electric switch valve 35, use single-path EGR cooling, and the control method is the same as above.

[0044] Dynamic temperature rise condition: measure the rotation speed of the first water pump 311 and / or the second water pump 312 under the median temperature condition in the temperature range [0, 100°C], [100°C, 200°C]…[800°C, 900°C], set the exhaust temperature slope to 15°C / min on the measurement and control unit, and dynamically adjust the start proportional valve opening using PID.

[0045] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0046] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0047] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0048] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0049] Although the embodiments of the present invention have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. An engine exhaust temperature control device, the engine exhaust temperature control device is used for selecting a three-way catalytic converter on a powertrain bench, characterized in that: The engine exhaust temperature control device comprises: A gas mixing control unit, the gas mixing control unit comprising a regulating valve; An exhaust pipeline unit, the exhaust pipeline unit comprising a first pipeline and a second pipeline, the regulating valve being arranged between the first pipeline and the second pipeline; An exhaust cooling unit, the exhaust cooling unit is arranged on the first pipeline, the exhaust cooling unit includes: an air inlet, an air outlet, a first air path and a second air path, the first air path and the second air path are arranged in parallel, the first air path is connected with the first pipeline through the air inlet and the air outlet, the second air path is connected with the first pipeline through the air inlet and the air outlet, a switch valve and a first cooler are arranged on the first air path, a second cooler is arranged on the second air path, and the first cooler is connected in series to the first cooling circuit, the second cooler is connected in series to the second cooling circuit, the first cooling circuit and the second cooling circuit are arranged in parallel and are both connected to a radiator.

2. The engine exhaust temperature control device according to claim 1, characterized in that: The exhaust cooling unit further includes: a first thermostat and a second thermostat, wherein the first thermostat is disposed in the first cooling circuit, and the second thermostat is disposed in the second cooling circuit.

3. The engine exhaust temperature control device according to claim 2, characterized in that: The exhaust cooling unit further includes: a first water pump and a second water pump, wherein the first water pump is disposed in the first cooling circuit, and the second water pump is disposed in the second cooling circuit.

4. The engine exhaust temperature control device according to claim 3, characterized in that: The exhaust cooling unit further includes a cooling fan, which is arranged close to the radiator and is used to cool the radiator.

5. The engine exhaust temperature control device according to claim 4, characterized in that: The exhaust cooling unit further includes: a pressure sensor and a first temperature sensor, both of which are disposed on the second gas path, and the pressure sensor is configured to monitor the gas path pressure and determine whether the exhaust cooling unit operates normally.

6. The engine exhaust temperature control device according to claim 1, characterized in that: The exhaust pipe unit further includes: a transfer flange, which is connected between the first pipe and the engine, and two ends of the second pipe are respectively connected to the transfer flange and the regulating valve.

7. The engine exhaust temperature control device according to claim 6, characterized in that: The second pipeline is arranged in parallel with the exhaust cooling unit.

8. The engine exhaust temperature control device according to claim 6, characterized in that: The exhaust pipe unit further includes: a third pipe, a three-way catalytic converter is passed through the third pipe, and exhaust direct sampling test pieces are provided at both ends of the three-way catalytic converter.

9. The engine exhaust temperature control device according to claim 8, characterized in that: The gas mixing control unit further includes: a second temperature sensor, which is disposed upstream of the three-way catalytic converter in the airflow direction and between the exhaust direct sampling test piece and the three-way catalytic converter.

10. The engine exhaust temperature control device according to any one of claims 1 to 9, characterized in that: Also includes: A measurement and control unit, wherein the measurement and control unit is electrically connected to the gas mixing control unit, the exhaust pipeline unit and the exhaust cooling unit.

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