A tail gas secondary combustion testing device

Abstract

The utility model belongs to tail gas emission test field discloses a kind of tail gas secondary combustion test devices, mainly for automobile tail gas emission test, with State environmental protection requirement of automobile is adjusted high, in order to meet the requirement of automobile tail gas emission to meet national emission standard, the utility model mainly through the experiment test equipment of simulating different flow tail gas and tail gas under different temperature influence on nitrogen oxides (NOx) after participating in engine secondary combustion.By simulating engine in different operating conditions inject different flow tail gas and different temperature tail gas participate in combustion after through instrument test emission tail gas nitrogen oxides (NOx) concentration, obtain the data of tail gas injection and engine operating condition, to obtain reference data for the design and optimization of engine tail gas secondary introduction engine combustion.

Description

Technical Field

[0001] This utility model relates to the field of exhaust emission testing, specifically an exhaust secondary combustion testing device. Background Technology

[0002] As the country raises its environmental protection requirements for automobiles, there is currently no suitable secondary combustion testing device for exhaust gases in order to meet the national emission standards for automobile exhaust emissions. Utility Model Content

[0003] To address the shortcomings of existing technologies, this invention provides a test device for secondary combustion of exhaust gas. This invention mainly simulates the impact of exhaust gas on nitrogen oxides (NOx) after secondary combustion in an engine.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: A secondary combustion exhaust gas testing device includes a nitrogen oxide analyzer, an engine, an engine intake pipe, an exhaust gas outlet temperature sensor, an exhaust gas proportioning valve, a flow meter, an exhaust gas cooler, a secondary combustion exhaust gas intake pipe, an exhaust gas intake temperature sensor, a controller, and a power supply. The secondary combustion exhaust gas intake pipe introduces exhaust gas into the secondary combustion exhaust gas pipeline. The secondary combustion exhaust gas pipeline is sequentially equipped with an exhaust gas intake temperature sensor, an exhaust gas proportioning valve, an exhaust gas cooler, a flow meter, and an exhaust gas outlet temperature sensor. The exhaust gas outlet temperature sensor is connected to the engine via the engine intake pipe. The nitrogen oxide analyzer is connected to the engine's exhaust gas outlet to detect the concentration of nitrogen oxides (NOx) in the engine's exhaust gas. The controller is electrically connected to the exhaust gas proportioning valve, the exhaust gas cooler, the flow meter, the exhaust gas outlet temperature sensor, and the exhaust gas intake temperature sensor. The power supply provides power to all electrical components within the device.

[0005] In a further optimized configuration, the exhaust gas proportional control valve is located between the exhaust gas intake temperature sensor and the exhaust gas cooler. The controller adjusts the opening of the exhaust gas proportional control valve by outputting a control signal, thereby controlling the amount of exhaust gas entering the secondary combustion chamber.

[0006] Furthermore, the exhaust gas cooler is located between the exhaust gas proportional regulating valve and the flow meter. The exhaust gas cooler is equipped with a cooling fan, and the controller adjusts the temperature of the exhaust gas participating in secondary combustion by steplessly adjusting the speed of the cooling fan. In a further optimized configuration, the flow meter is located between the exhaust gas cooler and the exhaust gas outlet temperature sensor. It is used to collect the exhaust gas flow data participating in secondary combustion and feed it back to the controller. The controller will adjust the opening of the exhaust gas proportional regulating valve according to the difference between the flow feedback value and the target flow setting value, so that the exhaust gas flow is stabilized within the target flow range.

[0007] Further optimization involves using an exhaust gas temperature sensor to collect exhaust gas temperature data before it enters the engine intake manifold and feed it back to the controller. The controller adjusts the speed of the exhaust gas cooler fan based on the difference between the temperature feedback value and the target temperature setting value, so that the exhaust gas temperature is stabilized within the target temperature range.

[0008] Further optimization involves using an exhaust gas inlet temperature sensor to collect initial exhaust gas temperature data entering the secondary combustion exhaust gas duct and feed it back to the controller. This provides an initial temperature reference for the controller to adjust the cooling fan speed of the exhaust gas cooler, and helps to correct the temperature adjustment parameters.

[0009] Further preferred, it also includes a host computer / HMI, which is connected to the controller for issuing control commands such as target flow rate and target temperature. The controller performs corresponding adjustment operations according to the received commands and can feed back the operating parameters of each component to the host computer / HMI.

[0010] This invention has the following beneficial effects: it is an experimental testing device for simulating the effect of exhaust gas on nitrogen oxides (NOx) after secondary combustion in an engine. Attached Figure Description

[0011] Figure 1 This is a system schematic diagram of the present invention; Figure 2 This is the electrical schematic diagram of this utility model. Detailed Implementation

[0012] The present invention will be further described below with reference to the accompanying drawings and relevant knowledge. Obviously, the described applications are only some embodiments of the present invention, and not all embodiments.

[0013] The present invention will be further described in detail below with reference to the accompanying drawings.

[0014] Reference Figures 1-2 As shown, a secondary combustion test device for exhaust gas includes a proportional control valve between the exhaust gas intake temperature and the exhaust gas cooler. This valve, controlled by a controller, adjusts the valve opening to regulate the amount of exhaust gas participating in combustion, thus simulating the effect of different exhaust gas flow rates on NOx in engine exhaust. Between the proportional valve and the flow meter is an exhaust gas cooler, which, through stepless adjustment of the internal cooling fan speed, cools the exhaust gas participating in secondary combustion, simulating the effect of different exhaust gas temperatures on NOx in engine exhaust. A flow meter and an exhaust gas outlet temperature sensor are installed between the engine intake pipe and the exhaust gas cooler. These sensors provide feedback on the exhaust gas outlet temperature and flow rate to the controller, which then controls the opening of the proportional control valve and the speed of the cooler fan based on the feedback values ​​and target setpoints.

[0015] The main components of this utility model are: 1. Nitrogen-oxygen analyzer; 2. Engine; 3. Engine intake pipe; 4. Exhaust gas outlet temperature sensor; 5. Exhaust gas proportional regulating valve; 6. Flow meter; 7. Exhaust gas cooler; 8. Exhaust gas secondary combustion intake pipe; 9. Exhaust gas intake temperature sensor; 10. Power supply; 11. Controller. In this invention, a nitrogen oxide analyzer 1 is used to analyze the NOx content in the exhaust gas. A secondary combustion intake pipe 8 is used to introduce exhaust gas into the secondary combustion exhaust gas pipe. An exhaust gas intake temperature sensor 9 is located on the secondary combustion exhaust gas pipe to collect the exhaust gas temperature. An exhaust gas proportional control valve 5 controls the flow rate of exhaust gas participating in secondary combustion by adjusting its opening. An exhaust gas cooler 7 regulates the temperature of the exhaust gas participating in secondary combustion by adjusting the speed of its cooling fan through a controller. A flow meter 6 provides feedback on the flow rate of exhaust gas participating in secondary combustion. The controller adjusts the opening of the proportional valve based on the feedback flow rate and the target flow rate to ensure a stable achievement of the target flow rate. An exhaust gas outlet temperature sensor 4 collects the temperature of the exhaust gas before it enters the engine intake pipe. The controller controls the speed of the cooling fan in the exhaust gas cooler 7 based on the temperature collected by the exhaust gas outlet temperature sensor 4 and the set target temperature to ensure a stable achievement of the target temperature required for testing. The exhaust gas participating in secondary combustion enters the engine 2 through the engine intake pipe 3 to participate in combustion.

[0016] Compared with existing technologies, the beneficial effects of this invention are: it allows for the adjustment of different flow rates and temperatures of secondary combustion exhaust gas, enabling the observation and testing of engine operating status and the concentration of nitrogen oxides (NOx) in the exhaust gas, providing data support for engine research, development, and upgrades. Control commands are issued via a host computer / HMI, and the controller executes these commands, ensuring operator safety. This invention, through optimized and innovative overall design and internal structure, simplifies the control method, reduces human intervention, lowers labor intensity, and improves economic efficiency by adopting advanced design concepts.

[0017] Further optimization, referring to Figures 1-2As shown, the nitrogen oxide analyzer 1 is connected to the exhaust gas secondary combustion intake pipe 8 to collect and test nitrogen oxides in the exhaust gas. The exhaust gas secondary combustion intake pipe 8 is connected to the engine 2 and the exhaust gas intake temperature sensor 9, respectively, splitting the exhaust gas emitted by the engine into two parts. One part is discharged after being detected by the nitrogen oxide analyzer 1 through the exhaust pipe, and the other part participates in the secondary combustion of exhaust gas. The exhaust gas intake temperature sensor 9 is connected to the exhaust gas proportional control valve 5. When the exhaust gas participating in the secondary combustion passes through the exhaust gas intake temperature sensor 9, the intake temperature sensor 9 collects the current temperature value and the value of the exhaust gas outlet temperature sensor 4 for flow count value correction. The exhaust gas proportional control valve 5 is connected to the exhaust gas cooler 7. The exhaust gas proportional control valve 5 is used to regulate the flow rate of the gas participating in the secondary combustion of exhaust gas. After the exhaust gas participating in the secondary combustion passes through the exhaust gas proportional control valve 5, it enters the exhaust gas cooler. The exhaust gas cooler 7 is connected to the flow meter 6. The function of the exhaust gas cooler is to reduce the temperature of the exhaust gas participating in secondary combustion in the engine. Simultaneously, the controller 11 controls the speed of the cooling fan in the exhaust gas cooler 7 to ensure that the temperature of the exhaust gas participating in secondary combustion reaches the required controlled temperature range. The flow meter 6 is connected to the exhaust gas outlet temperature sensor 4. After cooling, the exhaust gas passes through the flow meter 6, which collects the flow rate and feeds it back to the controller 11. The controller 11 then adjusts the opening of the exhaust gas proportional control valve 5. The exhaust gas outlet temperature sensor 4 is connected to the engine intake manifold 3. After passing through the flow meter 6, the exhaust gas participating in secondary combustion passes through the exhaust gas outlet temperature sensor 4. This sensor collects the temperature and feeds it back to the controller 11. The controller 11 adjusts the speed of the cooling fan in the exhaust gas cooler 7 based on the feedback outlet temperature. Finally, the exhaust gas participating in secondary combustion enters the engine through the engine intake manifold 3 to participate in combustion.

[0018] This invention discloses a secondary combustion testing device for exhaust gas. Through the coordinated control of an exhaust gas proportional control valve and an exhaust gas cooler, it can accurately simulate scenarios where exhaust gas of different flow rates and temperatures participates in secondary combustion in an engine. The controller adjusts the opening of the proportional valve and the speed of the cooler fan according to the set target values. Combined with real-time feedback from flow meters and temperature sensors, it ensures the stability and repeatability of the test conditions. By detecting the NOx concentration in the exhaust gas using a nitrogen oxide analyzer, the system can obtain correlation data between exhaust gas parameters (flow rate, temperature) and engine operating conditions, as well as NOx emissions. This provides a direct reference for optimizing the design of secondary combustion of engine exhaust gas (such as setting secondary intake flow rate thresholds and temperature ranges), effectively reducing engine NOx emissions and helping to meet national environmental protection standards. The device adopts closed-loop control logic of the controller, sensors, and actuators, eliminating the need for manual intervention in the flow and temperature adjustment process and significantly reducing human error. At the same time, by remotely issuing control commands via a host computer / HMI, operators do not need to have close contact with the engine and high-temperature exhaust gas pipes, significantly improving operational safety. The adaptive control also shortens the switching time between different test conditions, reduces the workload of experimental personnel, and improves testing efficiency. The overall structure of the device is compact, with components such as the inlet air temperature sensor, proportional control valve, cooler, flow meter, and outlet air temperature sensor connected sequentially on the secondary combustion exhaust gas pipeline. The signal transmission path is clear, facilitating installation, debugging, and maintenance. The controller simplifies the control process and reduces equipment failure rate by uniformly receiving feedback signals and outputting adjustment commands. In addition, the device can be reused for secondary combustion tests on different engine models without additional modifications, reducing equipment investment costs and demonstrating good economic efficiency and versatility.

[0019] In this utility model, the controller is a Siemens SR30, the proportional valve is a YCLT71, the condenser cooling fan is a YWF4E-200S, the flow meter is a LWGY-RL, and the temperature sensor is a K-type thermocouple sensor.

[0020] Example 1: A secondary combustion test device for exhaust gas includes a nitrogen-oxygen analyzer 1, an engine 2, an engine intake pipe 3, an exhaust gas outlet temperature sensor 4, an exhaust gas proportional control valve 5, a flow meter 6, an exhaust gas cooler 7, an exhaust gas secondary combustion intake pipe 8, an exhaust gas intake temperature sensor 9, a controller 11, a power supply 10, and a host computer / HMI.

[0021] The exhaust gas secondary combustion inlet pipe 8 is connected to the secondary combustion exhaust gas pipe. The exhaust gas inlet temperature sensor 9, exhaust gas proportional regulating valve 5, exhaust gas cooler 7, flow meter 6, and exhaust gas outlet temperature sensor 4 are installed on the pipe in sequence. The exhaust gas temperature sensor 4 is connected to the intake end of the engine 2 through the engine intake pipe 3, and the exhaust end of the engine 2 is connected to the nitrogen and oxygen analyzer 1. The controller 11 is electrically connected to the exhaust gas proportional regulating valve 5, the exhaust gas cooler 7, the flow meter 6, the exhaust gas outlet temperature sensor 4, and the exhaust gas inlet temperature sensor 9, respectively. The power supply 10 supplies power to the controller, sensors, cooler fan, and other electrical components. The host computer / HMI communicates with the controller 11 via wired or wireless means.

[0022] Nitrogen Oxygen Analyzer 1: Installed on the exhaust pipe of engine 2, it detects the concentration of nitrogen oxides (NOx) in the engine exhaust gas in real time and transmits the detection data to controller 11 or host computer as a core indicator for evaluating the secondary combustion effect.

[0023] Engine 2: As the test subject, it receives regulated secondary combustion exhaust gas and performs combustion operations to simulate actual operating conditions. By changing the engine's speed, load, and other operating parameters, the impact of secondary combustion on NOx emissions under different operating conditions can be tested.

[0024] Engine intake pipe 3: It delivers the exhaust gas, after temperature and flow regulation, to the intake system of engine 2. Its pipe diameter is designed to match the engine intake port to ensure that the exhaust gas enters the combustion chamber stably and reduce the impact of airflow disturbance on the combustion process.

[0025] Exhaust gas temperature sensor 4: Installed between flow meter 6 and engine intake pipe 3, it collects the temperature of exhaust gas before it enters the engine and feeds it back to controller 11. Its measurement range covers -40℃ to 300℃, with an accuracy of ±1℃. It provides a key feedback signal for the controller to adjust the exhaust gas cooler 7, ensuring that the exhaust gas temperature is stable at the target value, such as 50℃ to 200℃.

[0026] Exhaust gas proportional control valve 5: Located between exhaust gas inlet temperature sensor 9 and exhaust gas cooler 7, it receives PWM signals from controller 11 to adjust the valve opening, with an opening range of 0~100%, thereby controlling the flow rate of exhaust gas participating in secondary combustion, ranging from 0~200L / min. Its response time is ≤0.5s, ensuring the speed and accuracy of flow regulation.

[0027] Flow meter 6: Installed between the exhaust gas cooler 7 and the exhaust gas outlet temperature sensor 4, it adopts the electromagnetic or vortex flow measurement principle to collect the exhaust gas flow in real time, with a measurement accuracy of ±2%FS, and feeds it back to the controller 11. The controller adjusts the opening of the proportional control valve 5 according to the deviation between the flow feedback value and the target flow, realizing closed-loop control of the flow.

[0028] Exhaust gas cooler 7: Located between the exhaust gas proportional regulating valve 5 and the flow meter 6, it is equipped with a cooling fan with a speed adjustment range of 0~3000 r / min. The controller 11 adjusts the fan speed to change the heat dissipation efficiency, cooling the exhaust gas temperature from the initial temperature (e.g., 150℃~300℃) to the target temperature (e.g., 50℃~180℃). The cooler's heat dissipation capacity can meet the temperature regulation requirements under maximum exhaust gas flow, ensuring the stability of temperature regulation.

[0029] Secondary combustion exhaust gas intake pipe 8: Connects the engine's original exhaust pipe to the secondary combustion exhaust gas pipe, diverting part of the exhaust gas to the secondary combustion system. Its pipe diameter is designed according to the engine's exhaust volume to ensure a stable diversion process and not affect the engine's normal exhaust back pressure.

[0030] Exhaust gas intake temperature sensor 9: Installed on the pipe after the exhaust gas secondary combustion intake pipe 8, it collects the initial exhaust gas temperature entering the secondary combustion system (measurement range 0~300℃, accuracy ±1℃), providing an initial reference for the controller 11 to calculate the target fan speed of the exhaust gas cooler 7. If the initial temperature is high, the preset fan speed starting point is higher, shortening the response time of temperature adjustment.

[0031] Controller 11: Employs a PLC or embedded controller, receiving signals from flow meter 6, exhaust gas outlet temperature sensor 4, and exhaust gas inlet temperature sensor 9. It calculates the adjustment amount using a built-in PID algorithm and outputs control signals to the exhaust gas proportional control valve 5 and exhaust gas cooler 7, respectively. Simultaneously, the controller communicates with a host computer / HMI to receive control commands and upload operating parameters, such as real-time flow rate, temperature, and NOx concentration.

[0032] Power supply 10: Provides a stable power supply (e.g., DC24V, output power ≥500W) for controller 11, sensors, proportional control valves, cooler fans, etc., to ensure that each component works normally.

[0033] Host computer / HMI: Operators can set target flow rate, target temperature and engine operating parameters through its interface, and display the operating data of each component (such as current flow rate, temperature and NOx concentration) curves in real time, which facilitates the monitoring of the experimental process and data recording.

[0034] Workflow: Before the experiment, the target exhaust gas flow rate (e.g., 80L / min) and target temperature (e.g., 120℃) are set via the host computer / HMI, and engine 2 is started to the preset operating conditions (e.g., speed 2000r / min, load 50%).

[0035] The exhaust gas enters the pipeline through the exhaust gas secondary combustion intake pipe 8, and the exhaust gas intake temperature sensor 9 collects the initial temperature (e.g., 200℃) and sends it to the controller 11.

[0036] The controller 11 calculates the target fan speed (e.g., 1500 r / min) of the exhaust gas cooler 7 based on the initial temperature and the target temperature, and outputs a control signal. At the same time, it adjusts the initial opening degree (e.g., 40%) of the exhaust gas proportional control valve 5 according to the target flow rate.

[0037] After the exhaust gas flow rate is regulated by the proportional regulating valve 5, it enters the exhaust gas cooler 7 and is cooled to near the target temperature. Then, the real-time flow rate (e.g., 78 L / min) is detected by the flow meter 6. The flow meter feeds the data back to the controller, and the controller fine-tunes the opening of the proportional regulating valve to 42% to stabilize the flow rate at 80 L / min.

[0038] After cooling, the exhaust gas temperature is detected by exhaust gas outlet temperature sensor 4 (e.g., 118℃). The sensor feeds back the signal to the controller, which then finely adjusts the cooler fan speed to 1600r / min to stabilize the temperature at 120℃.

[0039] The qualified exhaust gas enters the engine 2 through the engine intake pipe 3 to participate in secondary combustion. The nitrogen oxygen analyzer 1 detects and records the NOx concentration in the exhaust gas (e.g., 150 ppm).

[0040] Repeat the above process, changing the target flow rate and temperature (e.g., flow rate 50 L / min, temperature 80℃); flow rate 120 L / min, temperature 150℃, etc., and collect NOx concentration data under different operating conditions to analyze and obtain the optimal secondary combustion parameters.

[0041] In this embodiment, the components work together to achieve precise testing of secondary combustion of exhaust gases at different flow rates and temperatures. Its technical features ensure the reliability and effectiveness of the experiment, and the obtained data provides strong support for the design optimization of secondary combustion of engine exhaust gases. By simulating the injection of exhaust gases at different flow rates and temperatures under different engine operating conditions, and then measuring the NOx concentration in the exhaust gases using instruments, data on exhaust gas injection and engine operating conditions are obtained. This provides reference data for the design and optimization of secondary combustion of engine exhaust gases.

[0042] This invention utilizes an experimental testing device to simulate the impact of exhaust gas at different flow rates and temperatures on NOx emissions from an engine after secondary combustion. By simulating the injection of exhaust gas at different flow rates and temperatures under varying engine operating conditions, the concentration of NOx in the emitted exhaust gas is measured using instruments. Data on the relationship between exhaust gas participation in secondary combustion and engine operating conditions is obtained, providing reference data for the design and optimization of secondary exhaust gas combustion in the engine. This reduces NOx emissions and ensures that vehicle emissions meet national environmental standards.

[0043] Although some embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, and all such changes and alterations should fall within the scope of the present invention.

Claims

1. A secondary combustion test device for exhaust gas, comprising a nitrogen-oxygen analyzer (1), an engine (2), an engine intake pipe (3), an exhaust gas outlet temperature sensor (4), an exhaust gas proportional control valve (5), a flow meter (6), an exhaust gas cooler (7), an exhaust gas secondary combustion intake pipe (8), and an exhaust gas intake temperature sensor (9); characterized in that: The exhaust gas secondary combustion intake pipe (8) is used to introduce exhaust gas into the secondary combustion exhaust gas pipe. The secondary combustion exhaust gas pipe is equipped with an exhaust gas intake temperature sensor (9), an exhaust gas proportional regulating valve (5), an exhaust gas cooler (7), a flow meter (6), and an exhaust gas outlet temperature sensor (4) in sequence. The exhaust gas outlet temperature sensor (4) is connected to the engine (2) through the engine intake pipe (3). The nitrogen oxide analyzer (1) is connected to the exhaust gas emission end of the engine (2) and is used to detect the concentration of nitrogen oxides in the exhaust gas emitted by the engine (2).

2. The exhaust gas secondary combustion testing device according to claim 1, characterized in that: The exhaust gas proportional control valve (5) is located between the exhaust gas inlet temperature sensor (9) and the exhaust gas cooler (7).

3. The exhaust gas secondary combustion testing device according to claim 1, characterized in that: The exhaust gas cooler (7) is located between the exhaust gas proportional regulating valve (5) and the flow meter (6), and the exhaust gas cooler (7) is equipped with a cooling fan.

4. The exhaust gas secondary combustion testing device according to claim 1, characterized in that: It also includes a controller (11) and a power supply (10); the controller (11) is electrically connected to the exhaust gas proportional regulating valve (5), the exhaust gas cooler (7), the flow meter (6), the exhaust gas outlet temperature sensor (4), and the exhaust gas inlet temperature sensor (9), respectively. The power supply (10) supplies power to each electrical component in the device. The controller (11) adjusts the opening of the exhaust gas proportional regulating valve (5) by outputting control signals to control the amount of exhaust gas entering the secondary combustion. The controller (11) adjusts the temperature of the exhaust gas entering the secondary combustion by steplessly adjusting the speed of the cooling fan.

5. The exhaust gas secondary combustion testing device according to claim 4, characterized in that: The flow meter (6) is located between the exhaust gas cooler (7) and the exhaust gas outlet temperature sensor (4). The flow meter (6) is used to collect the exhaust gas flow data participating in secondary combustion and feed it back to the controller (11). The controller (11) adjusts the opening of the exhaust gas proportional regulating valve (5) according to the difference between the flow feedback value and the target flow setting value, so that the exhaust gas flow is stable within the target flow range.

6. The exhaust gas secondary combustion testing device according to claim 5, characterized in that: The exhaust gas temperature sensor (4) is used to collect exhaust gas temperature data before entering the engine intake pipe (3) and feed it back to the controller (11). The controller (11) adjusts the speed of the exhaust gas cooler (7) cooling fan according to the difference between the temperature feedback value and the target temperature setting value, so that the exhaust gas temperature is stable within the target temperature range.

7. The exhaust gas secondary combustion testing device according to claim 1, characterized in that: The exhaust gas inlet temperature sensor (9) is used to collect the initial exhaust gas temperature data entering the secondary combustion exhaust gas pipeline and feed it back to the controller (11), providing an initial temperature reference for the controller (11) to adjust the cooling fan speed of the exhaust gas cooler (7) and assisting in correcting the temperature adjustment parameters.

Images