Dual-fuel mode EGR rate dynamic optimization control system

Abstract

The utility model discloses a marine engine technical field's a kind of EGR rate dynamic optimization control system under dual-fuel mode, comprising: mixing box, and the intake pipe of dual-fuel engine intercommunication;Main exhaust box, and the exhaust pipe of dual-fuel engine is communicated with by pipeline in its air inlet end, and exhaust end is communicated with mixing box by pipeline;Exhaust manifold, and exhaust pipe intercommunication;At least two auxiliary exhaust boxes, and the air inlet end of auxiliary exhaust box is communicated with exhaust manifold by pipeline, and exhaust end is communicated with mixing box by pipeline;Wherein, main exhaust box and the air inlet end of auxiliary exhaust box are equipped with EGR valve, and the air inlet end of auxiliary exhaust box is also equipped with conveying equipment;Sensor assembly for determining the exhaust gas parameter in main exhaust box and auxiliary exhaust box is equipped. The device uses the collaborative mechanism of recirculation exhaust composition optimization and EGR rate dynamic correction, when dual-fuel engine DRF changes sharply, or when condition mutates, avoid EGR rate change amplitude too big, greatly promote combustion stability.

Description

Technical Field

[0001] This utility model relates to the field of marine engine technology, specifically to a dynamic optimization control system for EGR rate in dual-fuel mode. Background Technology

[0002] Dual-fuel engines (such as diesel and natural gas) can reduce fuel consumption by 10%-15% and reduce soot emissions by 30%-40% through the mixed combustion of two fuels. However, they also face technical challenges such as complex exhaust gas composition and large fluctuations in operating conditions. Under different fuel replacement rates (DRF), the exhaust gases emitted by the engine show significant differences in parameters such as NOx concentration, HC types, and temperature, which places higher demands on the adaptability and control precision of the exhaust gas recirculation (EGR) system.

[0003] When a dual-fuel engine switches between diesel and natural gas modes (i.e., the fuel replacement rate (DRF) changes drastically) or is subjected to sudden changes in operating conditions such as rapid acceleration or cold start, the traditional EGR control strategy must significantly adjust the EGR rate (e.g., from 25% in diesel mode to below 20% in natural gas mode) to meet the emission requirements of different modes due to the significant differences in combustion characteristics of different fuels (e.g., natural gas has a slow combustion speed, high unburned HC, and is sensitive to dilution).

[0004] However, drastic fluctuations in the EGR rate can lead to sudden changes in intake dilution, a sharp drop in combustion temperature, or a lean mixture, which can easily cause problems such as unstable combustion, misfire, power lag, or even knocking, severely restricting the smoothness of operation and emission consistency of dual-fuel engines.

[0005] In addition, traditional EGR relies solely on real-time exhaust gas, the composition of which fluctuates drastically with operating conditions, resulting in significant differences in actual emission performance at the same EGR rate, making precise control difficult.

[0006] To address these issues, a dynamic optimization control system for EGR rate under dual-fuel mode is provided. Utility Model Content

[0007] The purpose of this invention is to provide a dynamic optimization control system for EGR rate in dual-fuel mode, which solves the problem of combustion instability caused by passive and large-scale adjustment of EGR rate when the fuel replacement rate changes drastically or the operating conditions change abruptly in existing dual-fuel engines.

[0008] This utility model achieves the above objectives through the following technical solutions: A dynamic optimization control system for EGR rate in dual-fuel mode includes: The mixing chamber is connected to the intake manifold of the dual-fuel engine; The main exhaust gas box has its intake end connected to the exhaust pipe of the dual-fuel engine via a pipe, and its exhaust end connected to the mixing box via a pipe. Exhaust manifold, which is connected to the exhaust pipe; At least two auxiliary exhaust gas boxes, with the intake end of the auxiliary exhaust gas box connected to the exhaust manifold via a pipe, and the exhaust end connected to the mixing box via a pipe; The main exhaust gas box and the auxiliary exhaust gas box are both equipped with EGR valves at their inlet and outlet ends, and the auxiliary exhaust gas box is also equipped with conveying equipment at its inlet and outlet ends. Both the main exhaust gas box and the auxiliary exhaust gas box are equipped with sensor components for measuring the parameters of the exhaust gas inside. The auxiliary exhaust gas box is also equipped with a catalytic adsorption module for purifying the exhaust gas. The auxiliary exhaust gas box stores compliant exhaust gas. The main exhaust gas box and the auxiliary exhaust gas box, based on the operating conditions of the dual-fuel engine, individually or collaboratively input recirculated exhaust gas into the mixing box.

[0009] As a further optimization of this utility model, the mixing box is provided with a fuel gas input pipe and an air input pipe; the exhaust pipe is provided with control valves downstream of the intake pipe connection point of the main exhaust gas box and the exhaust manifold connection point.

[0010] As a further optimization of this utility model, one end of the auxiliary exhaust gas box is rotatably provided with an exhaust gas inlet pipe, a drive assembly for driving the rotation of the exhaust gas inlet pipe located on the side of the exhaust gas inlet pipe, and a rotary joint located at the end of the exhaust gas inlet pipe; the other end of the auxiliary exhaust gas box is fixedly provided with an exhaust gas outlet pipe; a dynamic catalytic assembly is provided inside the auxiliary exhaust gas box, the dynamic catalytic assembly includes a rotating cylinder coaxially and fixedly connected to the exhaust gas inlet pipe, a catalytic module sleeved on the outer periphery of the rotating cylinder, a retainer fixedly located on the inner wall of the auxiliary exhaust gas box for positioning the catalytic module, and a fixed cylinder fixedly located on the end face of the auxiliary exhaust gas box and clearance-fitted with the other end of the rotating cylinder.

[0011] As a further optimization of this utility model, a partition is fixedly provided inside the rotating cylinder to divide the rotating cylinder into two independent airflow chambers. A first through hole is uniformly opened on the circumferential sidewall of one airflow chamber, and a second through hole is uniformly opened on the circumferential sidewall of the other airflow chamber. The retainer includes a ring body and multiple fan-shaped blocks fixed on the outer periphery of the ring body. The auxiliary exhaust gas box, the rotating cylinder, and the fan-shaped blocks enclose multiple catalytic chambers, and the catalytic modules are embedded in each catalytic chamber one by one. An exhaust gas channel is opened on the fan-shaped block at the position corresponding to the first through hole. The first through hole is periodically aligned with the catalytic chamber to directly impact the catalytic module, or aligned with the exhaust gas channel to laterally impact the catalytic module.

[0012] As a further optimization of this utility model, the exhaust gas channel includes a main channel extending radially along the fan-shaped block, and at least two branch channels, which are symmetrically arranged on both sides of the main channel and their outlet ends are respectively connected to two adjacent catalytic chambers.

[0013] As a further optimization of this utility model, a plurality of third through holes are provided on the circumferential sidewall of the fixed cylinder at the position corresponding to the second through hole; the second through hole is periodically aligned or misaligned with the third through hole to pulse-type deliver fresh exhaust gas into the inner cavity of the fixed cylinder.

[0014] As a further optimization of this utility model, the inner cavity of the fixed cylinder is provided with a stirring assembly, which includes a stirring rod fixedly mounted on a partition plate and multiple sets of stirring blades mounted on the stirring rod.

[0015] As a further optimization of this utility model, the sensor assembly is disposed in the inner cavity of the fixed cylinder.

[0016] The beneficial effects of this utility model are as follows: 1. This utility model adopts a synergistic mechanism of recirculated exhaust gas composition optimization and EGR rate dynamic correction. When the DRF of a dual-fuel engine changes drastically or when the operating conditions change abruptly, the EGR rate adjustment range can be controlled within ±3%, which greatly improves combustion stability. Furthermore, the composition adjustment ensures that the actual emission effect meets the standards. Under inefficient operating conditions, high CO2 and low O2 compliant exhaust gas is introduced, which significantly improves the dilution efficiency and thermal buffering capacity of EGR. It is suitable for emission and stability optimization of dual-fuel engines under complex operating conditions such as fuel switching and cold start.

[0017] 2. This utility model uses at least two auxiliary exhaust gas boxes to ensure that the mixing box always has a sufficient supply of qualified exhaust gas, avoiding the problem of EGR interruption when a single auxiliary exhaust gas box is replenished.

[0018] 3. This utility model uses the continuous rotation of the rotating cylinder to make the newly introduced waste gas pass through an alternating pattern of forward and lateral impact, so as to achieve uniform distribution of waste gas among multiple catalytic chambers and full contact with the catalytic module to achieve efficient purification. The newly introduced waste gas enters the inner cavity of the fixed cylinder in a pulse form through the second through hole, and mixes with the remaining previously qualified waste gas in the inner cavity through the impact, which promotes the homogenization of waste gas. At the same time, the stirring component operates synchronously to further promote the mixing of the newly introduced waste gas and the previously qualified waste gas, ensuring the uniformity of waste gas composition. Attached Figure Description

[0019] Figure 1 This is a schematic diagram illustrating the process principle of this utility model; Figure 2 This is a schematic diagram of the auxiliary exhaust gas box structure of this utility model. Figure 1 ; Figure 3 This is a schematic diagram of the auxiliary exhaust gas box structure of this utility model. Figure 2 ; Figure 4 This is a schematic diagram of the rotating cylinder structure of the auxiliary waste gas box of this utility model; Figure 5 This is a partial structural cross-sectional view of the auxiliary exhaust gas box of this utility model; Figure 6 This is a schematic diagram of the connection structure between the catalytic module and the retainer in the auxiliary exhaust gas box of this utility model; Figure 7 This is a schematic diagram of the fixed cylinder structure of the auxiliary waste gas box of this utility model.

[0020] In the picture: 1. Dual-fuel engine; 101. Intake pipe; 102. Exhaust pipe; 103. Control valve; 2. Main exhaust gas box; 3. Auxiliary exhaust gas box; 301. Exhaust gas inlet pipe; 302. Exhaust gas outlet pipe; 303. Drive assembly; 304. Rotating cylinder; 304a. Baffle plate; 304b. First through hole; 304c. Second through hole; 305. Catalytic converter module; 306. Fixed cylinder; 306a. Third through hole; 307. Stirring assembly; 307a. Stirring rod; 307b. Stirring blade; 308. Holder; 308a. Ring body; 308b. Sector block; 308c. Catalytic converter chamber; 308d. Exhaust gas passage; 308e. Main passage; 308f. Branch passage; 4. Mixing box; 401. Fuel gas inlet pipe; 402. Air inlet pipe; 5. Exhaust manifold; 6. EGR valve; 7. Conveying equipment. Detailed Implementation

[0021] The present application will now be described in further detail with reference to the accompanying drawings. It should be noted that the following specific embodiments are only used to further illustrate the present application and should not be construed as limiting the scope of protection of the present application. Those skilled in the art can make some non-essential improvements and adjustments to the present application based on the above application content.

[0022] Example 1 To address the combustion instability issue in existing dual-fuel engines caused by the passive and significant adjustment of the EGR rate during drastic changes in fuel replacement rate (DRF) or abrupt changes in operating conditions, please refer to [link to relevant documentation]. Figure 1 This utility model provides a dynamic optimization control system for EGR rate in dual-fuel mode, comprising: The mixing chamber 4 is connected to the intake pipe 101 of the dual-fuel engine 1; The main exhaust gas box 2 has its intake end connected to the exhaust pipe 102 of the dual-fuel engine 1 via a pipe, and its exhaust end connected to the mixing box 4 via a pipe. Exhaust manifold 5, which is connected to exhaust pipe 102; At least two auxiliary exhaust gas boxes 3, the intake end of the auxiliary exhaust gas box 3 is connected to the exhaust manifold 5 through a pipe, and the exhaust end is connected to the mixing box 4 through a pipe; Among them, the main exhaust gas box 2 and the auxiliary exhaust gas box 3 are equipped with EGR valves 6 at the inlet and outlet ends, and the auxiliary exhaust gas box 3 is also equipped with conveying equipment 7 at the inlet and outlet ends. Both the main exhaust gas box 2 and the auxiliary exhaust gas box 3 are equipped with sensor components for measuring the parameters of the exhaust gas inside. The exhaust gas parameters include, but are not limited to, CO2 concentration, O2 concentration, HC content, temperature and pressure. The auxiliary exhaust gas box 3 is also equipped with a catalytic adsorption module for purifying the exhaust gas. The pollutants include, but are not limited to, NOx and HC. The auxiliary exhaust gas box 3 stores qualified exhaust gas, which is the exhaust gas discharged by the dual-fuel engine 1 under the operating conditions of load ≥ 50% of rated load, speed fluctuation rate ≤ ±2%, combustion cycle variation rate COVimep ≤ 5%, and coolant temperature ≥ 80℃. The main exhaust gas box 2 and the auxiliary exhaust gas box 3 input recirculated exhaust gas into the mixing box 4 individually or in combination based on the operating conditions of the dual-fuel engine 1.

[0023] The mixing chamber 4 is equipped with a fuel gas input pipe 401 and an air input pipe 402. The mixing chamber 4 is equipped with a corresponding turbulence structure to ensure that the real-time exhaust gas, compliant exhaust gas, air and fuel gas are mixed evenly to avoid local high concentrations that lead to unstable combustion. The exhaust pipe 102 is equipped with a control valve 103 downstream of the intake pipe connection point of the main exhaust gas box 2 and the connection point of the exhaust manifold 5.

[0024] The system control method includes the following steps: S1. When the dual-fuel engine 1 is operating under steady-state conditions, the sensor components in the main exhaust gas box 2 monitor the exhaust gas composition in real time, including: CO2 concentration, O2 concentration, HC (hydrocarbon) content, temperature and pressure. When the exhaust gas is detected to meet the preset standard for compliant exhaust gas (e.g., CO2 ≥ 10%, O2 ≤ 5%, HC ≤ 200 ppm), only the main exhaust gas box 2 is needed to supply recirculated exhaust gas to the mixing box 4. The EGR valves 6 at the inlet and outlet of each auxiliary exhaust gas box 3 are closed and do not participate in exhaust gas recirculation. The steady-state condition is when the dual-fuel engine 1 is operating at a load ≥ 50% of the rated load, a speed fluctuation rate ≤ ±2%, a combustion cycle variation rate COVimep ≤ 5%, and a coolant temperature ≥ 80℃. S2. When the dual-fuel engine 1 is operating under non-steady-state conditions (such as idling, cold start, low load, fuel switching, rapid acceleration, etc.), the main exhaust gas box 2 continues to input real-time exhaust gas into the mixing box 4. At the same time, the EGR valve 6 and conveying device 7 of at least one auxiliary exhaust gas box 3 that has stored qualified exhaust gas are opened to deliver the qualified exhaust gas to the mixing box 4 as needed, mix it with the real-time exhaust gas, dilute the oxygen concentration in the intake air, and form recirculated exhaust gas with controllable composition and stable thermodynamic properties to reduce the combustion temperature and suppress NOx generation. Alternatively, the qualified exhaust gas can be delivered to the mixing box 4 separately. The non-steady-state conditions are all operating conditions other than the steady-state conditions. Furthermore, the ratio of real-time exhaust gas to compliant exhaust gas is dynamically adjusted based on the real-time operating conditions of engine 1 (speed, load, air-fuel ratio, fuel type) and the target effective EGR rate. By adjusting the proportion of compliant exhaust gas, the dilution capacity and heat capacity of the mixed exhaust gas are optimized, NOx generation is suppressed and combustion stability is maintained. S3. The mixing box 4 receives real-time exhaust gas from the main exhaust gas box 2 and qualified exhaust gas from the auxiliary exhaust gas box 3. Fuel gas is introduced through the fuel gas input pipe 401 and combustion air is introduced through the air input pipe 402. After the various gases are fully mixed in the mixing box 4, they finally re-enter the combustion chamber of the dual-fuel engine 1 through the air intake pipe 101 to complete the cycle.

[0025] When the amount of compliant exhaust gas remaining in any of the auxiliary exhaust gas boxes 3 drops to a set threshold (e.g., 15%), the control system will automatically perform the following operations: The downstream EGR valve 6 of the auxiliary exhaust gas box 3 is closed to stop the gas supply to the mixing box 4. Another auxiliary exhaust gas box 3 is activated to continue supplying compliant exhaust gas to the mixing box 4, ensuring that the mixing box 4 always has a sufficient supply of compliant exhaust gas. For the closed auxiliary exhaust gas box 3, the exhaust gas composition is monitored in real time by the sensor components in the main exhaust gas box 2. When the exhaust gas is detected to meet the preset compliant exhaust gas standard, the control system opens the upstream EGR valve 6 of the closed auxiliary exhaust gas box 3 and introduces real-time compliant exhaust gas into it through the exhaust manifold 5 to supplement it. The newly introduced exhaust gas mixes with the remaining previously compliant exhaust gas to form new compliant exhaust gas, ready for the next use.

[0026] Traditional EGR control often requires significant adjustments to the EGR rate (such as from 25% to 20% or lower) when switching between dual-fuel modes (e.g., diesel and natural gas) to address the differences in NOx and unburned HC emission characteristics. Large fluctuations in the EGR rate can easily cause abrupt changes in intake dilution, leading to combustion phase shifts, misfires, or delayed power response. This solution introduces highly inert, compliant exhaust gas as a regulating medium. Between diesel mode (DRF=0%) and natural gas mode (DRF=100%), the EGR rate only needs to be slightly adjusted (e.g., from 25% to 23%), avoiding combustion instability caused by drastic changes in flow rate. By optimizing the composition to meet different DRF requirements, in diesel mode, the high CO2 characteristics of the real-time exhaust gas (12%–15%), supplemented by a small amount of compliant exhaust gas, can achieve efficient NOx suppression. In natural gas mode, although the EGR rate only decreases slightly, by significantly increasing the proportion of compliant exhaust gas (which is treated by catalytic adsorption, HC < 150 ppm), the active hydrocarbon content in the recirculated exhaust gas is significantly reduced, the generation of unburned HC is suppressed, and the heat capacity of the mixture is increased to prevent the combustion temperature from being too high.

[0027] Example 2 Based on Example 1, in order to solve the problems of unstable exhaust gas quality and insufficient uniformity of exhaust gas composition in the EGR system, such as... Figures 2-6 As shown, one end of the auxiliary exhaust gas box 3 is rotatably provided with an exhaust gas inlet pipe 301, a drive assembly 303 located on the side of the exhaust gas inlet pipe 301 for driving its rotation, and a rotary joint located at the end of the exhaust gas inlet pipe 301. The other end of the auxiliary exhaust gas box 3 is fixedly provided with an exhaust gas outlet pipe 302. The auxiliary exhaust gas box 3 is provided with a dynamic catalytic assembly, which includes a rotating cylinder 304 coaxially fixedly connected to the exhaust gas inlet pipe 301, a catalytic module 305 sleeved on the outer periphery of the rotating cylinder 304, a retainer 308 fixedly provided on the inner wall of the auxiliary exhaust gas box 3 for positioning the catalytic module 305, and a fixed cylinder 306 fixedly provided on the end face of the auxiliary exhaust gas box 3 and clearance-fitted with the other end of the rotating cylinder 304.

[0028] A partition 304a is fixedly installed inside the rotating cylinder 304 to divide the rotating cylinder 304 into two independent airflow chambers. A first through hole 304b is evenly opened on the circumferential sidewall of one airflow chamber, and a second through hole 304c is evenly opened on the circumferential sidewall of the other airflow chamber. The retainer 308 includes a ring body 308a and a plurality of sector-shaped blocks 308b fixedly disposed on the outer periphery of the ring body 308a. The auxiliary exhaust gas box 3, the rotating cylinder 304 and the sector-shaped blocks 308b enclose and form a plurality of Catalytic chambers 308c and catalytic modules 305 are embedded in each catalytic chamber 308c in a corresponding manner. A waste gas channel 308d is provided on the fan-shaped block 308b at the position corresponding to the first through hole 304b. The first through hole 304b is periodically aligned with the catalytic chamber 308c to directly impact the catalytic module 305, or aligned with the waste gas channel 308d to laterally impact the catalytic module 305. The catalytic module 305 is a porous media catalytic module, which is selected based on the specific dual-fuel type.

[0029] The exhaust gas passage 308d includes a main passage 308e extending radially along the fan-shaped block 308b, and at least two branch passages 308f. The branch passages 308f are symmetrically arranged on both sides of the main passage 308e and their outlet ends are respectively connected to two adjacent catalytic chambers 308c, so that the lateral impact airflow can act on two adjacent catalytic modules 305 at the same time.

[0030] like Figure 7As shown, multiple third through holes 306a are provided on the circumferential sidewall of the fixed cylinder 306 at positions corresponding to the second through hole 304c. The second through hole 304c periodically aligns with or misaligns with the third through hole 306a, pulse-likely delivering new exhaust gas into the inner cavity of the fixed cylinder 306, where it mixes with the remaining previously compliant exhaust gas in the inner cavity to obtain new compliant exhaust gas. When the second through hole 304c aligns with the third through hole 306a, the new exhaust gas enters the inner cavity of the fixed cylinder 306 in a pulsed manner. When the two are misaligned, the exhaust gas flow is blocked. This periodic alignment and misalignment mechanism allows the new exhaust gas to enter the fixed cylinder 306 in a pulsed manner, mixing with the remaining previously compliant exhaust gas in the inner cavity, thus promoting the homogenization of the exhaust gas.

[0031] like Figure 4 As shown, the inner cavity of the fixed cylinder 306 is provided with a stirring assembly 307. The stirring assembly 307 includes a stirring rod 307a fixedly mounted on the partition plate 304a, and multiple sets of stirring blades 307b mounted on the stirring rod 307a. The stirring blades 307b rotate under the drive of the stirring rod 307a, further promoting the mixing of the newly introduced waste gas with the previously qualified waste gas, and ensuring the uniformity of the waste gas composition.

[0032] The sensor assembly is located in the inner cavity of the fixed cylinder 306, and the sensor assembly also includes a sensor for measuring the remaining amount of qualified exhaust gas.

[0033] The specific workflow for replenishing new exhaust gas into the auxiliary exhaust gas box 3 is as follows: The drive assembly 303 drives the exhaust gas inlet pipe 301 to rotate at a low speed, and the rotating cylinder 304, coaxially fixed with the exhaust gas inlet pipe 301, rotates synchronously; the upstream EGR valve 6 of the auxiliary exhaust gas box 3 opens, and the downstream EGR valve 6 closes, ready to receive new exhaust gas; after being diverted by the exhaust manifold 5, the new exhaust gas enters the rotating cylinder 304 through the rotary joint at the end of the exhaust gas inlet pipe 301. The continuous rotation of the rotating cylinder 304 causes the new exhaust gas to fully contact the catalytic module 305 through alternating forward and side impacts, achieving efficient purification of pollutants such as NOx and HC. This ensures that the recirculated exhaust gas entering the combustion chamber has excellent characteristics of low pollutant content and high inert components, effectively suppressing NO during combustion. x The regeneration of the gas can also reduce the emissions of unburned hydrocarbons. The newly introduced exhaust gas, after catalytic treatment, moves axially along the auxiliary exhaust gas box 3 to the second through hole 304c. It is then injected into the inner cavity of the fixed cylinder 306 through the second through hole 304c and mixed evenly with the previously qualified exhaust gas to obtain new qualified exhaust gas.

[0034] The embodiments described above are merely examples of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of this utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these modifications and improvements all fall within the protection scope of this utility model.

Claims

1. A dual-fuel mode EGR rate dynamic optimization control system, characterized in that, include: The mixing chamber (4) is connected to the intake pipe (101) of the dual-fuel engine (1); The main exhaust gas box (2) has its intake end connected to the exhaust pipe (102) of the dual-fuel engine (1) through a pipe, and its exhaust end connected to the mixing box (4) through a pipe. An exhaust manifold (5) is connected to the exhaust pipe (102); At least two auxiliary exhaust gas boxes (3), the intake end of the auxiliary exhaust gas box (3) is connected to the exhaust manifold (5) through a pipe, and the exhaust end is connected to the mixing box (4) through a pipe; The main exhaust gas box (2) and the auxiliary exhaust gas box (3) are equipped with EGR valves (6) at their inlet and outlet ends, and the auxiliary exhaust gas box (3) is also equipped with conveying equipment (7) at its inlet and outlet ends. Both the main exhaust gas box (2) and the auxiliary exhaust gas box (3) are equipped with sensor components for measuring the parameters of the exhaust gas inside them. The auxiliary exhaust gas box (3) is also equipped with a catalytic adsorption module for purifying the exhaust gas. The auxiliary exhaust gas box (3) stores qualified exhaust gas. The main exhaust gas box (2) and the auxiliary exhaust gas box (3) input recirculated exhaust gas into the mixing box (4) individually or in combination based on the operating conditions of the dual-fuel engine (1).

2. The dual fuel mode EGR rate dynamic optimization control system of claim 1, wherein, The mixing box (4) is equipped with a fuel gas input pipe (401) and an air input pipe (402). The exhaust pipe (102) is equipped with control valves (103) at the inlet pipe connection point of the main exhaust gas box (2) and downstream of the inlet pipe connection point of the exhaust manifold (5).

3. The dual fuel mode EGR rate dynamic optimization control system of claim 1, wherein, The auxiliary exhaust gas box (3) is rotatably provided with an exhaust gas inlet pipe (301), a drive assembly (303) for driving the rotation of the exhaust gas inlet pipe (301) located on the side of the exhaust gas inlet pipe (301), and a rotary joint located at the end of the exhaust gas inlet pipe (301). The other end of the auxiliary exhaust gas box (3) is fixedly provided with an exhaust gas outlet pipe (302). The auxiliary exhaust gas box (3) is equipped with a dynamic catalytic component, which includes a rotating cylinder (304) coaxially and fixedly connected to the exhaust gas input pipe (301), a catalytic module (305) sleeved on the outer periphery of the rotating cylinder (304), a retainer (308) fixedly disposed on the inner wall of the auxiliary exhaust gas box (3) and used to position the catalytic module (305), and a fixed cylinder (306) fixedly disposed on the end face of the auxiliary exhaust gas box (3) and clearance-fitted with the other end of the rotating cylinder (304).

4. The dual fuel mode EGR rate dynamic optimization control system of claim 3, wherein, The rotating cylinder (304) is fixedly provided with a partition (304a) to divide the rotating cylinder (304) into two independent airflow chambers. A first through hole (304b) is uniformly opened on the circumferential sidewall of one of the airflow chambers, and a second through hole (304c) is uniformly opened on the circumferential sidewall of the other airflow chamber. The retainer (308) includes a ring body (308a) and a plurality of fan-shaped blocks (308b) fixed on the outer periphery of the ring body (308a). The auxiliary exhaust gas box (3), the rotating cylinder (304) and the fan-shaped blocks (308b) enclose a plurality of catalytic chambers (308c). The catalytic modules (305) are embedded in each catalytic chamber (308c) in a corresponding manner. An exhaust gas channel (308d) is provided on the sector block (308b) at the position corresponding to the first through hole (304b). The first through hole (304b) is periodically aligned with the catalyst chamber (308c) to directly impact the catalyst module (305), or aligned with the exhaust gas channel (308d) to laterally impact the catalyst module (305).

5. The dual fuel mode EGR rate dynamic optimization control system of claim 4, wherein, The exhaust gas passage (308d) includes a main passage (308e) extending radially along the fan-shaped block (308b) and at least two branch passages (308f). The branch passages (308f) are symmetrically arranged on both sides of the main passage (308e) and their outlet ends are respectively connected to two adjacent catalytic chambers (308c).

6. The dual fuel mode EGR rate dynamic optimization control system of claim 4, wherein, The fixed cylinder (306) has multiple third through holes (306a) at the positions corresponding to the second through hole (304c) on its circumferential sidewall. The second through hole (304c) is periodically aligned or misaligned with the third through hole (306a) to pulse-transmit fresh exhaust gas into the inner cavity of the fixed cylinder (306).

7. The dual fuel mode EGR rate dynamic optimization control system of claim 4, wherein, The inner cavity of the fixed cylinder (306) is provided with a stirring assembly (307), which includes a stirring rod (307a) fixed on a partition plate (304a) and multiple stirring blades (307b) on the stirring rod (307a).

8. The dual fuel mode EGR rate dynamic optimization control system of claim 7, wherein, The sensor assembly is located inside the cavity of the fixed cylinder (306).

Images