Methanol-diesel oil-hydrogen energy multi-fuel self-adaptive dynamic coupling system for inland ship

Abstract

The invention discloses a methanol-diesel oil-hydrogen energy multi-fuel self-adaptive dynamic coupling system for an inland ship. The methanol-diesel oil-hydrogen energy multi-fuel self-adaptive dynamic coupling system comprises a multi-fuel independent storage and accurate supply subsystem, a methanol online catalytic hydrolysis hydrogen production subsystem, an intelligent fuel control subsystem, an engine main body and a whole-process safety protection subsystem. The multi-fuel system stores and conveys fuel, the hydrogen production subsystem generates hydrogen, the intelligent unit collects parameters and controls fuel supply, and the safety system monitors and protects. According to the system, through multi-fuel cooperation and online hydrogen production, the problems that single diesel oil is high in pollution and hydrogen energy is difficult to store and transport are solved; intelligent control adapts to working conditions to adjust fuel proportion, and economical efficiency is improved by more than 15%; nitrogen oxides are reduced by 40% and particulate matters are reduced by 65% by the stratified combustion technology; and reliable operation is ensured through full-process protection. The method is suitable for frequent starting and stopping of inland ships and variable working condition scenes and has good application prospects.

Description

Technical Field

[0001] This invention belongs to the field of marine technology. Specifically, this invention relates to a methanol-diesel-hydrogen multi-fuel adaptive power coupling system for inland waterway vessels. Background Technology

[0002] Currently, inland waterway vessel propulsion systems mainly rely on diesel fuel, which suffers from high emissions, high fuel costs, and poor adaptability to various operating conditions. Hydrogen energy, as a clean energy source, faces limitations in its application in the marine sector due to its low storage and transportation safety and high cost. While methanol fuel is convenient to store, its power performance is insufficient when used alone, failing to meet the demands of high-load ship operations.

[0003] Existing dual-fuel power systems generally lack online hydrogen production capabilities and multi-parameter intelligent adaptive control capabilities, making it impossible to accurately allocate fuel and achieve efficient combustion according to the complex and ever-changing navigation conditions of ships, and thus difficult to balance environmental protection, economy, and power.

[0004] This invention provides a methanol-diesel-hydrogen multi-fuel adaptive power coupling system for inland waterway vessels, particularly focusing on how to achieve efficient, clean, and reliable operation of the vessel's power system through integrated design of multi-fuel coordinated supply, online hydrogen production, intelligent control, and combustion optimization, thus achieving a balance between environmental protection, economy, and power performance. Summary of the Invention

[0005] This invention aims to at least solve one of the technical problems existing in the prior art. To this end, this invention provides a methanol-diesel-hydrogen multi-fuel adaptive power coupling system for inland waterway vessels, with the goal of achieving a balance between environmental friendliness, economy, and power performance.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a methanol-diesel-hydrogen multi-fuel adaptive power coupling system for inland waterway vessels, including a multi-fuel independent storage and precise supply subsystem, a methanol online catalytic hydrolysis hydrogen production subsystem, a multi-parameter adaptive intelligent fuel control unit, an engine body, and a full-process safety protection subsystem. The multi-fuel independent storage and precise supply subsystem is connected to the methanol online catalytic hydrolysis hydrogen production subsystem and the engine body, respectively, and is used to store methanol and diesel, and to supply methanol to the methanol online catalytic hydrolysis hydrogen production subsystem, and to supply diesel and hydrogen generated by the methanol online catalytic hydrolysis hydrogen production subsystem to the engine body; The multi-parameter adaptive intelligent fuel control unit is electrically connected to the multi-fuel independent storage and precise supply subsystem, the methanol online catalytic hydrolysis hydrogen production subsystem, and the engine main body, respectively, and is used to collect parameters and control the operating status and fuel supply ratio of each subsystem according to the parameters. The full-process safety protection subsystem is electrically connected to the multi-fuel independent storage and precise supply subsystem, the methanol online catalytic hydrolysis hydrogen production subsystem, the engine body, and the multi-parameter adaptive intelligent fuel control unit, respectively, and is used to monitor the system safety status and perform protective actions.

[0007] The multi-fuel independent storage and precise supply subsystem includes a methanol storage and transportation component, a diesel storage and transportation component, and a hydrogen storage and transportation component; The methanol storage and transportation assembly includes a methanol storage tank with a double-layer insulation structure. The inner layer of the methanol storage tank is made of 316L stainless steel, and the outer layer is made of Q235 steel. The space between the inner and outer layers is filled with insulation cotton. The methanol storage tank is equipped with a liquid level sensor and a pressure sensor. The diesel storage and transportation assembly includes a diesel storage tank, an electric heating device, an oil temperature sensor, and a flow sensor. The electric heating device is configured to automatically start when the ambient temperature is below 5°C. The hydrogen storage and delivery assembly includes a buffer tank, a purity sensor, and a pressure reducing valve, wherein the working pressure of the buffer tank is set to 35 MPa. The pressure reducing valve is connected to the buffer tank and reduces the pressure from 35MPa to 0.8MPa.

[0008] The methanol storage and delivery assembly also includes a variable frequency metering pump and a filter, with the variable frequency metering pump connected to the methanol storage tank and the filter.

[0009] The methanol online catalytic hydrolysis hydrogen production subsystem includes a tubular reactor, a feed pump, and an online hydrogen purity analyzer. Engine cooling water is introduced into the jacket of the tubular reactor. The feed pump mixes methanol and deionized water at a molar ratio of 1:1.2 and feeds them into the tubular reactor, with a flow rate range of 0-30 L / min. A reaction pressure sensor is installed on the tubular reactor. When the reaction pressure sensor detects that the pressure of the tubular reactor is higher than 0.8 MPa, the pressure relief valve connected to the tubular reactor opens, and the excess gas is introduced into the combustion chamber of the engine body for combustion.

[0010] The multi-parameter adaptive intelligent fuel control unit uses a Siemens S7-1500 series PLC, and the parameters collected include fuel balance signal, engine operating condition signal and navigation demand signal. The fuel balance signals include methanol level, hydrogen buffer tank pressure, and diesel level. When the methanol level is below 20% and the hydrogen buffer tank pressure is below 5MPa, it is determined that the fuel is insufficient. When the diesel level is below 10%, a low fuel level alarm is triggered. The engine operating condition signals include speed 0-2000 r / min, load 0-100%, and exhaust temperature 300-600℃; The navigation demand signal determines whether the ship is in a low-speed cruising, constant-speed navigation, or high-speed sprint state through the ship's GPS and rudder angle sensor.

[0011] The control strategies executed by the multi-parameter adaptive intelligent fuel control unit include: Low-speed cruising mode: The engine speed is below 800 r / min, the load is less than 30%, the hydrogen supply accounts for 80% of the total fuel, the diesel supply accounts for 20%, and the methanol metering pump delivers at a flow rate of 30 L / min. Uniform speed navigation: Engine speed 800-1500 r / min, load 30%-70%, hydrogen 50%, diesel 50%, for every 10% increase in engine load, diesel supply increases by 8% and hydrogen supply increases by 2%; High-speed sprint state: The engine speed is higher than 1500r / min, the load is greater than 70%, the diesel fuel accounts for 80%, the hydrogen fuel accounts for 20%, and the diesel heating device is started. Fuel shortage emergency mode: When the methanol level is below 20% or the hydrogen pressure is below 5MPa, the diesel supply is increased to 90%, and the maximum engine speed is limited to 1500r / min.

[0012] The engine body includes a dual-chamber combustion chamber, a diesel injector, an annular jet ring, and a swirl control valve; The dual-chamber combustion chamber includes a pre-combustion chamber and a main combustion chamber. The pre-combustion chamber is located at the top of the cylinder head and has a volume of 15% of the total combustion chamber volume. The diesel injector is installed in the pre-combustion chamber, with an injection pressure of 180 MPa and an injector orifice diameter of 0.15 mm. The annular jet ring is located in the middle of the cylinder wall of the main combustion chamber, with 8 jet holes, the hole diameter is set to 0.5 mm, and the hydrogen injection velocity is set to 30 m / s; The vortex control valve is installed at the top of the main combustion chamber, and the valve opening adjustment range is set to 0-30°.

[0013] An engine crankshaft position sensor is installed on the engine body. The engine crankshaft position sensor controls the fuel injection timing. Diesel is injected 15° before the piston compression stroke top dead center, and hydrogen is injected 3° after the diesel injection. For every 200 r / min increase in engine speed, the diesel injection advance angle increases by 1° crankshaft angle, and the hydrogen injection delay angle decreases by 0.5° crankshaft angle.

[0014] The entire process safety protection subsystem includes gas sensors, ventilation fans, audible and visual alarms, explosion-proof cameras, temperature control components, and safety valves; The gas sensor is installed along the methanol and hydrogen delivery pipelines. The detection limit for methanol is 500 ppm and the detection limit for hydrogen is 1000 ppm. When a leak is detected, the corresponding fuel shut-off valve is closed, the ventilation fan is started, and the audible and visual alarm is triggered. The explosion-proof camera is located in the hydrogen storage tank area; The temperature control component is used to monitor the exhaust temperature of the engine block. When the temperature exceeds 600°C, the diesel supply is reduced by 10% and the cooling water flow rate is increased. When the temperature reaches 650°C, an emergency shutdown is triggered. The safety valve is installed in the hydrogen production subsystem. When the gas pressure is higher than 1 MPa, it automatically activates to release pressure, and the released gas is introduced into the combustion chamber for combustion.

[0015] This invention relates to a methanol-diesel-hydrogen multi-fuel adaptive power coupling system for inland waterway vessels, and has the following beneficial effects: By employing multi-fuel synergistic supply and online hydrogen production technology, the system effectively solves the problems of high pollution from single-fuel diesel and difficulties in hydrogen storage and transportation. Intelligent control strategies enable the system to adaptively adjust fuel ratios according to ship navigation conditions, improving fuel economy by over 15%. Stratified combustion technology reduces nitrogen oxide emissions by 40% and particulate matter emissions by 65%, meeting increasingly stringent environmental requirements. A comprehensive safety protection mechanism ensures reliable system operation under various conditions. This system is particularly suitable for the frequent start-stop and variable operating scenarios of inland waterway vessels, demonstrating promising application prospects and significant potential for widespread adoption. Attached Figure Description

[0016] This manual includes the following figures, which illustrate the following: Figure 1 This is a block diagram of the methanol-diesel-hydrogen multi-fuel adaptive power coupling system for inland waterway vessels according to the present invention. Figure 2 This is a block diagram of the entire process security protection subsystem; Figure 3 This is a schematic diagram of the engine cylinder structure. Detailed Implementation

[0017] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings, in order to help those skilled in the art to have a more complete, accurate and in-depth understanding of the concept and technical solutions of the present invention, and to facilitate its implementation.

[0018] This invention provides a methanol-diesel-hydrogen multi-fuel adaptive power coupling system for inland waterway vessels, including a multi-fuel independent storage and precise supply subsystem, a methanol online catalytic hydrolysis hydrogen production subsystem, a multi-parameter adaptive intelligent fuel control unit, an engine body, and a full-process safety protection subsystem.

[0019] Specifically, in this embodiment of the invention, the multi-fuel independent storage and precise supply subsystem is connected to the methanol online catalytic hydrolysis hydrogen production subsystem and the engine body, respectively, for storing methanol and diesel and supplying methanol to the methanol online catalytic hydrolysis hydrogen production subsystem, and supplying diesel and hydrogen generated by the methanol online catalytic hydrolysis hydrogen production subsystem to the engine body.

[0020] The multi-parameter adaptive intelligent fuel control unit is electrically connected to the multi-fuel independent storage and precise supply subsystem, the methanol online catalytic hydrolysis hydrogen production subsystem, and the engine main body, respectively, to collect parameters and control the operating status and fuel supply ratio of each subsystem based on the parameters.

[0021] The full-process safety protection subsystem is electrically connected to the multi-fuel independent storage and precise supply subsystem, the methanol online catalytic hydrolysis hydrogen production subsystem, the engine body, and the multi-parameter adaptive intelligent fuel control unit, respectively, to monitor the system safety status and perform protective actions.

[0022] In this embodiment of the invention, the multi-fuel independent storage and precise supply subsystem includes a methanol storage and transportation component, a diesel storage and transportation component, and a hydrogen storage and transportation component; and dedicated storage and transportation devices are designed for the different physicochemical properties of methanol, diesel, and hydrogen.

[0023] In this embodiment of the invention, the methanol storage and transportation assembly includes a methanol storage tank with a double-layer insulation structure. The inner layer of the methanol storage tank is made of 316L stainless steel, and the outer layer is made of Q235 steel. The space between the inner and outer layers is filled with insulation cotton with a thickness of 50mm. The methanol storage tank is equipped with a high-precision liquid level sensor and a pressure sensor to monitor the methanol balance and tank pressure in real time to prevent evaporation and leakage.

[0024] In this embodiment of the invention, the methanol storage and delivery assembly further includes a variable frequency metering pump and a filter, with the variable frequency metering pump connected to the methanol storage tank and the filter. The methanol storage tank has an outlet at its bottom, through which the filter and the variable frequency metering pump are connected in sequence via a corrosion-resistant polytetrafluoroethylene (PTFE) pipe. The filter, with a filtration accuracy of 10 μm, is installed on the pipeline between the methanol storage tank outlet and the variable frequency metering pump, and is used to remove impurities from the methanol, protecting subsequent pump bodies and equipment. The inlet of the variable frequency metering pump is connected to the filter outlet, and the outlet is connected to a downstream methanol online catalytic hydrolysis hydrogen production module or engine supply pipeline. Its flow rate adjustment range is 0-50 L / min with an accuracy of ±2%, allowing for precise adjustment of the methanol delivery rate according to instructions from the intelligent control unit, achieving on-demand supply.

[0025] In this embodiment of the invention, the diesel storage and transportation assembly includes a diesel storage tank, an electric heating device, an oil temperature sensor, and a flow sensor, with the oil temperature sensor and flow sensor mounted on the diesel storage tank. The electric heating device has a power of 5kW and is configured to automatically start when the ambient temperature is below 5°C. The electric heating device is used to heat the diesel fuel and prevent it from solidifying.

[0026] The electric heating device (such as a heating element or heating jacket) is installed directly inside the diesel storage tank or attached to the outer wall of the tank, and connected to the intelligent fuel control unit via wires. The probe end of the oil temperature sensor is inserted into the diesel fuel in the tank, and the signal output end is also connected to the intelligent fuel control unit. When the oil temperature sensor detects that the diesel fuel temperature in the tank is below 5°C, it sends a signal to the intelligent fuel control unit, triggering the electric heating device to start heating. After the temperature rises back to the set value (such as 10°C), the intelligent fuel control unit instructs the electric heating device to shut off. The outlet of the diesel storage tank is connected to the inlet of the flow sensor via a metal delivery pipeline. The outlet of the flow sensor is then connected to the engine block via a pipeline to monitor the diesel fuel flow data output from the storage tank in real time and feed the signal back to the intelligent control unit to adjust the fuel supply.

[0027] In this embodiment of the invention, the hydrogen storage and delivery assembly includes a buffer tank, a purity sensor, and a pressure reducing valve. The buffer tank is made of carbon fiber composite material, and the working pressure of the buffer tank is set to 35 MPa with a safety factor of not less than 2.4, which complies with GB / T 355 standard. It is equipped with a hydrogen purity sensor with a purity of not less than 99.95%, and the outer layer of the buffer tank is wrapped with explosion-proof and heat-insulating material.

[0028] A pressure-reducing regulating valve is connected to the buffer tank, reducing the pressure from 35 MPa to 0.8 MPa. The buffer tank has inlet and outlet ports; the inlet connects to the output of the online methanol catalytic hydrolysis hydrogen production subsystem, and the outlet connects to the input of the pressure-reducing regulating valve via a pipeline. A purity sensor probe is connected to the pipeline between the buffer tank outlet and the pressure-reducing regulating valve, collecting hydrogen samples in real time through a sampling tube. The detection accuracy ensures that the hydrogen purity is not less than 99.95%, and the detection signal is transmitted to the intelligent control unit for monitoring hydrogen quality. The pressure-reducing regulating valve's input is connected to the buffer tank outlet pipeline, and its output is connected to the downstream main hydrogen delivery pipeline. Its adjustment range is set to reduce the high-pressure hydrogen from 35 MPa to a working pressure of 0.8 MPa. The valve body is made of 316L stainless steel and equipped with a pressure feedback device, which can dynamically stabilize the output pressure according to downstream demand, ensuring safe and controllable hydrogen delivery.

[0029] In this embodiment of the invention, each fuel is transported through an independent pipeline system: methanol is transported using corrosion-resistant polytetrafluoroethylene (PTFE) pipes, equipped with a variable frequency metering pump with a flow rate adjustment range of 0-50 L / min and an accuracy of ±2%, and a filter with a filtration accuracy of 10 μm; the diesel pipeline is equipped with a flow sensor with a range of 0-100 L / min; hydrogen is transported using 316L stainless steel pipes, equipped with a pressure reducing valve to reduce the pressure from 35 MPa to 0.8 MPa, and an electromagnetic shut-off valve with a response time of less than 0.1 s is installed. The pipeline joints adopt a double compression fitting sealing structure with a leakage rate of less than 1 × 10⁻⁻⁻⁶. 9 Pa•m³ / s.

[0030] The methanol online catalytic hydrolysis hydrogen production subsystem converts methanol into hydrogen through a catalytic hydrolysis reaction, avoiding the safety risks of long-distance hydrogen storage and transportation. In this embodiment of the invention, the methanol online catalytic hydrolysis hydrogen production subsystem includes a tubular reactor, a feed pump, an online hydrogen purity analyzer, and a reaction pressure sensor. Engine cooling water is introduced into the jacket of the tubular reactor.

[0031] The feed pump inlet is connected via pipelines to the outlet of the methanol storage tank and the deionized water supply device, while the outlet is directly connected to the feed inlet of the tubular reactor via corrosion-resistant pipelines. The feed pump is a variable frequency metering pump, capable of precisely controlling the intake of the two feedstocks at a preset methanol-water molar ratio of 1:1.2, with a flow rate adjustment range of 0-30 L / min, ensuring a stable delivery of the mixed feedstock to the reactor. The feed pump is electrically connected to the intelligent control unit, and its flow rate can be dynamically adjusted based on parameters such as reactor pressure and hydrogen purity (e.g., increasing water supply if purity is insufficient).

[0032] The tubular reactor has a diameter of 300 mm and a length of 1200 mm, employing a jacketed design. The inner tubes are filled with a palladium-based composite catalyst (5% palladium content, supported by γ-Al₂O₃, with a specific surface area of ​​200 m² / g; the catalyst particles have a honeycomb structure with a pore size of 5 mm to increase the reaction contact area). The outer jacket is used to introduce engine cooling water. The tubular reactor is fixed in a ventilated and dry area of ​​the ship's engine room. Connections to the feed pump and subsequent hydrogen delivery pipelines are all sealed with flanges to prevent methanol vapor or hydrogen leakage. The cooling water inlet of the tubular reactor jacket is connected to the engine cooling water pipeline, and the outlet returns to the cooling system. The reaction temperature inside the tubes is maintained stable at 120-150℃ through water temperature regulation.

[0033] The detection end of the reaction pressure sensor is directly installed on the top or side of the tubular reactor (near the gas outlet), communicating with the reactor interior to directly detect the pressure in the reaction chamber. The reaction pressure sensor has a range of 0-1 MPa and an accuracy of ±0.5% FS, and its signal output is electrically connected to the intelligent control unit. When the detected pressure exceeds 0.8 MPa, the control unit automatically triggers the pressure relief valve at the top of the reactor to open, allowing excess gas (methanol vapor and hydrogen mixture) to be introduced into the engine combustion chamber for combustion through a dedicated pipeline, thus avoiding the risk of overpressure.

[0034] The sampling probe of the online hydrogen purity analyzer is connected via a branch pipeline to the main pipeline between the hydrogen outlet of the reactor and the subsequent hydrogen buffer tank. The sampling point is close to the reactor outlet to ensure that fresh reaction products are collected. The online hydrogen purity analyzer has a detection range of 95%-100% and an accuracy of ≤0.1%, and can analyze in real time whether the hydrogen purity meets the requirement of 99% or higher.

[0035] The detection signal from the online hydrogen purity analyzer is transmitted to the intelligent control unit in real time. If the purity is lower than 99%, the control unit immediately instructs the feed pump to adjust the methanol-water mixing ratio (increase the supply of deionized water) until the purity meets the standard. If the purity continues to fail to meet the standard, an audible and visual warning is triggered to maintain the catalyst.

[0036] The feed pump delivers a proportionally mixed methanol-water mixture into the tubular reactor, where a hydrolysis reaction occurs under the action of a catalyst and jacket heating. The reaction pressure sensor and the online hydrogen purity analyzer monitor the reaction pressure and hydrogen quality, respectively. After the data is fed back to the intelligent control unit, the entire closed-loop control of raw material delivery, reaction process and product quality is achieved by adjusting the feed pump flow rate and controlling the pressure relief valve.

[0037] The system automatically prompts for catalyst replacement after 600 hours of use. Thanks to its detachable reactor structure, the replacement process can be completed within 2 hours. This module achieves a methanol conversion rate of over 98% and a hydrogen production efficiency of 92%. Each kg of methanol consumed produces 0.19 kg of hydrogen, meeting 30%-40% of the power requirements for ships traveling at low to medium speeds.

[0038] In this embodiment of the invention, the multi-parameter adaptive intelligent fuel control unit uses a marine-specific programmable logic controller (PLC) as its core. The PLC employs a Siemens S7-1500 series PLC as its main controller and achieves real-time control of multiple fuel supplies, the hydrogen production module, and engine operating conditions through modular design. It achieves adaptive switching and supply adjustment of fuel by collecting 12 key parameters. The sampling interval of the intelligent fuel control unit is set to 100ms to ensure rapid response to parameter acquisition and control commands.

[0039] The collected parameters include fuel balance signal, engine operating condition signal, and navigation demand signal; The fuel level signals include methanol level signal, hydrogen buffer tank pressure signal and diesel level signal. When the methanol level is below 20% and the hydrogen buffer tank pressure is below 5MPa, it is determined that the fuel is insufficient. When the diesel level is below 10%, a low fuel level alarm is triggered. Engine operating condition signals include speed 0-2000r / min, load 0-100%, and exhaust temperature 300-600℃; The navigation demand signal determines whether the ship is cruising at low speed, sailing at a constant speed, or sprinting at high speed through the ship's GPS and rudder angle sensors.

[0040] The methanol level signal is collected by a high-precision capacitive level sensor installed inside the methanol storage tank, and the signal is transmitted to the intelligent fuel control unit. When the level is below 20%, the intelligent fuel control unit determines that methanol is insufficient and triggers a fuel switching warning.

[0041] Hydrogen pressure signal: A piezoelectric pressure sensor installed on the outlet pipeline of the hydrogen buffer tank monitors the tank pressure in real time, and the hydrogen pressure signal is input to the intelligent fuel control unit. When the pressure is below 5 MPa, it is determined that the hydrogen energy is insufficient.

[0042] The liquid level sensor in the diesel storage tank collects liquid level data. When the liquid level is below 10%, the intelligent fuel control unit outputs a switch signal to the audible and visual alarm device, triggering a low oil level alarm.

[0043] GPS signals are used to acquire real-time speed data via the ship's GPS receiver. Combined with steering signals from the rudder angle sensor, the intelligent fuel control unit uses a preset algorithm to determine the ship's operating status. Low-speed cruise: speed < 5 knots and rudder angle change < 5 / s; Uniform speed navigation: speed of 5-15 knots and rudder angle change <10 / s; High-speed sprint: speed > 15 knots or rudder angle change > 10 / s (acceleration condition).

[0044] In this embodiment of the invention, the control strategy executed by the multi-parameter adaptive intelligent fuel control unit includes: Low-speed cruise mode: The engine speed is below 800 r / min, the engine load is less than 30%, the hydrogen supply accounts for 80% of the total fuel, the diesel supply accounts for 20% of the total fuel, and the methanol metering pump delivers at a flow rate of 30 L / min. Under constant speed navigation conditions: the main engine speed is 800-1500 r / min, the load is 30%-70%, the hydrogen supply accounts for 50% of the total fuel, the diesel supply accounts for 50% of the total fuel, and for every 10% increase in engine load, the diesel supply increases by 8% and the hydrogen supply increases by 2%. High-speed sprint state: The engine speed is higher than 1500r / min, the load is greater than 70%, the diesel supply accounts for 80% of the total fuel, the hydrogen supply accounts for 20% of the total fuel, and the electric heating device is started to heat the diesel. Fuel shortage emergency mode: When the methanol level is below 20% or the hydrogen pressure is below 5MPa, the diesel supply is increased to 90%, and the maximum engine speed is limited to 1500r / min.

[0045] In low-speed cruising mode, the intelligent fuel control unit outputs a control signal to the methanol variable frequency metering pump, which operates at a flow rate of 30L / min to ensure that the hydrogen production module produces hydrogen at full load, while achieving a supply ratio of 80% hydrogen and 20% diesel. The feed pump maintains a methanol-water mixing ratio of 1:1.2, and the reaction temperature is dynamically adjusted by the flow rate of the jacket cooling water.

[0046] During constant speed navigation, the initial supply ratio is set to 50% hydrogen and 50% diesel. The intelligent fuel control unit compares the deviation between the current load and the reference load (50%) in real time. When the load increases by 10%, the intelligent fuel control unit increases the diesel supply by 8% (corresponding to an 8% increase in the PWM duty cycle of the injection pump) and the hydrogen supply by 2% (corresponding to a 2% increase in the opening of the electromagnetic proportional valve) through a PID adjustment algorithm, keeping the total energy supply stable. If the engine speed fluctuates by more than ±50 r / min, the intelligent fuel control unit achieves closed-loop speed control by adjusting the total fuel supply (within ±5%).

[0047] During high-speed acceleration, the intelligent fuel control unit outputs a switch signal to activate the electric heating device of the diesel storage tank, while simultaneously controlling the heating temperature (maintained at 15-25℃) through a closed-loop control system using an oil temperature sensor; the hydrogen electromagnetic proportional valve opening is fixed at 20%, and the diesel injection pump PWM duty cycle is set to 80% to ensure high power output; if the engine exhaust temperature exceeds 550℃, the cooling fan is triggered to run at high speed in advance to prevent overheating.

[0048] In the low fuel emergency mode, when the methanol level is <20% or the hydrogen pressure is <5MPa, the intelligent fuel control unit immediately performs the following actions: The diesel supply ratio has been increased to 90% (90% PWM duty cycle of injection pump), while the hydrogen supply ratio has been reduced to 10%. The maximum speed is limited to 1500 r / min by the engine electronic speed governor; The cockpit display showed a "low fuel" warning and recorded the emergency mode activation time and parameters.

[0049] In this embodiment of the invention, efficient and clean combustion of hydrogen-diesel is achieved through improvements in the engine combustion chamber structure and optimization of fuel injection timing. The stratified combustion structure design employs a dual-chamber structure consisting of a pre-combustion chamber and a main combustion chamber. The engine body includes a dual-chamber combustion chamber, a diesel injector, an annular jet ring, and a swirl control valve. The dual-chamber combustion chamber comprises a pre-combustion chamber and a main combustion chamber. The pre-combustion chamber is located at the top of the cylinder head and has a volume of 15% of the total combustion chamber volume. The diesel injector is installed in the pre-combustion chamber, with an injection pressure of 180 MPa and an injector orifice diameter of 0.15 mm. In the main combustion chamber, hydrogen is injected through the annular jet ring, which is located in the middle of the cylinder wall of the main combustion chamber and has eight jet holes with a diameter of 0.5 mm. The hydrogen injection velocity is set to 30 m / s, forming an annular combustion zone. A swirl control valve is installed at the top of the main combustion chamber, generating an intake swirl by adjusting the valve opening from 0-30°. The swirl control valve is installed at the top of the main combustion chamber, with an valve opening adjustment range of 0-30°.

[0050] An engine crankshaft position sensor is installed on the engine block. This sensor controls the fuel injection timing, acquiring piston stroke signals with an accuracy of ±1° crankshaft angle to precisely control fuel injection timing. Diesel fuel is injected 15° before the piston reaches top dead center during the compression stroke, ensuring stable ignition in the pre-combustion chamber. Hydrogen is injected into the main combustion chamber 3° after diesel fuel injection, at which point a flame core has formed in the pre-combustion chamber, allowing for rapid ignition of the hydrogen. The injection timing is dynamically adjusted with engine speed: for every 200 rpm increase in speed, the diesel injection advance angle increases by 1° crankshaft angle, and the hydrogen injection delay angle decreases by 0.5° crankshaft angle, ensuring optimal combustion phase at different speeds. Through stratified combustion and precise injection, the system achieves significant emission reductions: nitrogen oxide emissions are reduced by 40%, particulate matter emissions by 65%, and thermal efficiency is improved by 15%.

[0051] In this embodiment of the invention, the full-process safety protection subsystem includes a gas sensor, a ventilation fan, an audible and visual alarm, an explosion-proof camera, a temperature control component, and a safety valve. The ventilation fan has an air volume of 1000 m³ / h.

[0052] Gas sensors are installed along the methanol and hydrogen pipelines. The detection limit for methanol is 500 ppm and the detection limit for hydrogen is 1000 ppm. When a leak is detected, the corresponding fuel shut-off valve is closed, the ventilation fan is started, and the audible and visual alarm is triggered. The audible and visual alarm includes a red warning light and an 80 dB buzzer. Explosion-proof cameras are installed in the hydrogen storage tank area to monitor the tank status in real time. The temperature control component monitors the exhaust temperature of the engine block. When the temperature exceeds 600°C, it reduces the diesel supply by 10% and increases the coolant flow rate. When the temperature reaches 650°C, it triggers an emergency shutdown. The safety valve is installed in the hydrogen production subsystem. When the gas pressure is higher than 1 MPa, it automatically activates to release pressure, and the released gas is introduced into the combustion chamber for combustion.

[0053] All electrical equipment is designed to be explosion-proof, with an explosion-proof rating of Ex d IIB T4 Ga, ensuring safe operation of the system.

[0054] The present invention has been described above by way of example with reference to the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any non-substantial improvements made using the inventive concept and technical solution; or the direct application of the inventive concept and technical solution to other situations without modification, are all within the protection scope of the present invention.

Claims

1. A methanol-diesel-hydrogen multi-fuel adaptive power coupling system for inland waterway vessels, characterized in that, It includes a multi-fuel independent storage and precise supply subsystem, a methanol online catalytic hydrolysis hydrogen production subsystem, a multi-parameter adaptive intelligent fuel control unit, an engine body, and a full-process safety protection subsystem; The multi-fuel independent storage and precise supply subsystem is connected to the methanol online catalytic hydrolysis hydrogen production subsystem and the engine body, respectively, and is used to store methanol and diesel, and to supply methanol to the methanol online catalytic hydrolysis hydrogen production subsystem, and to supply diesel and hydrogen generated by the methanol online catalytic hydrolysis hydrogen production subsystem to the engine body; The multi-parameter adaptive intelligent fuel control unit is electrically connected to the multi-fuel independent storage and precise supply subsystem, the methanol online catalytic hydrolysis hydrogen production subsystem, and the engine main body, respectively, and is used to collect parameters and control the operating status and fuel supply ratio of each subsystem according to the parameters. The full-process safety protection subsystem is electrically connected to the multi-fuel independent storage and precise supply subsystem, the methanol online catalytic hydrolysis hydrogen production subsystem, the engine body, and the multi-parameter adaptive intelligent fuel control unit, respectively, and is used to monitor the system safety status and perform protective actions.

2. The methanol-diesel-hydrogen multi-fuel adaptive power coupling system for inland waterway vessels according to claim 1, characterized in that, The multi-fuel independent storage and precise supply subsystem includes a methanol storage and transportation component, a diesel storage and transportation component, and a hydrogen storage and transportation component; The methanol storage and transportation assembly includes a methanol storage tank with a double-layer insulation structure. The inner layer of the methanol storage tank is made of 316L stainless steel, and the outer layer is made of Q235 steel. The space between the inner and outer layers is filled with insulation cotton. The methanol storage tank is equipped with a liquid level sensor and a pressure sensor. The diesel storage and transportation assembly includes a diesel storage tank, an electric heating device, an oil temperature sensor, and a flow sensor. The electric heating device is configured to automatically start when the ambient temperature is below 5°C. The hydrogen storage and delivery assembly includes a buffer tank, a purity sensor, and a pressure reducing valve, wherein the working pressure of the buffer tank is set to 35 MPa. The pressure reducing valve is connected to the buffer tank and reduces the pressure from 35MPa to 0.8MPa.

3. The methanol-diesel-hydrogen multi-fuel adaptive power coupling system for inland waterway vessels according to claim 2, characterized in that, The methanol storage and delivery assembly also includes a variable frequency metering pump and a filter, with the variable frequency metering pump connected to the methanol storage tank and the filter.

4. The methanol-diesel-hydrogen multi-fuel adaptive power coupling system for inland waterway vessels according to any one of claims 1 to 3, characterized in that, The methanol online catalytic hydrolysis hydrogen production subsystem includes a tubular reactor, a feed pump, and an online hydrogen purity analyzer. Engine cooling water is introduced into the jacket of the tubular reactor. The feed pump mixes methanol and deionized water at a molar ratio of 1:1.2 and feeds them into the tubular reactor, with a flow rate range of 0-30 L / min.

5. The methanol-diesel-hydrogen multi-fuel adaptive power coupling system for inland waterway vessels according to claim 4, characterized in that, A reaction pressure sensor is installed on the tubular reactor. When the reaction pressure sensor detects that the pressure of the tubular reactor is higher than 0.8 MPa, the pressure relief valve connected to the tubular reactor opens, and the excess gas is introduced into the combustion chamber of the engine body for combustion.

6. The methanol-diesel-hydrogen multi-fuel adaptive power coupling system for inland waterway vessels according to any one of claims 1 to 5, characterized in that, The multi-parameter adaptive intelligent fuel control unit uses a Siemens S7-1500 series PLC, and the parameters collected include fuel balance signal, engine operating condition signal and navigation demand signal. The fuel balance signals include methanol level, hydrogen buffer tank pressure, and diesel level. When the methanol level is below 20% and the hydrogen buffer tank pressure is below 5MPa, it is determined that the fuel is insufficient. When the diesel level is below 10%, a low fuel level alarm is triggered. The engine operating condition signals include speed 0-2000 r / min, load 0-100%, and exhaust temperature 300-600℃; The navigation demand signal determines whether the ship is in a low-speed cruising, constant-speed navigation, or high-speed sprint state through the ship's GPS and rudder angle sensor.

7. The methanol-diesel-hydrogen multi-fuel adaptive power coupling system for inland waterway vessels according to claim 6, characterized in that, The control strategies executed by the multi-parameter adaptive intelligent fuel control unit include: The engine's main body speed is below 800 r / min, the load is less than 30%, hydrogen supply accounts for 80% of the total fuel, diesel accounts for 20%, and the methanol metering pump delivers at a flow rate of 30 L / min. The engine's main speed is 800-1500 r / min, the load is 30%-70%, the hydrogen content is 50%, and the diesel content is 50%. For every 10% increase in engine load, the diesel supply increases by 8% and the hydrogen supply increases by 2%. When the engine speed is above 1500 r / min, the load is above 70%, the diesel fuel accounts for 80% of the fuel and the hydrogen fuel accounts for 20%, the diesel heating device is started. When the methanol level is below 20% or the hydrogen pressure is below 5 MPa, the diesel supply is increased to 90%, and the maximum engine speed is limited to 1500 r / min.

8. The methanol-diesel-hydrogen multi-fuel adaptive power coupling system for inland waterway vessels according to any one of claims 1 to 5, characterized in that, The engine body includes a dual-chamber combustion chamber, a diesel injector, an annular jet ring, and a swirl control valve; The dual-chamber combustion chamber includes a pre-combustion chamber and a main combustion chamber. The pre-combustion chamber is located at the top of the cylinder head and has a volume of 15% of the total combustion chamber volume. The diesel injector is installed in the pre-combustion chamber, with an injection pressure of 180 MPa and an injector orifice diameter of 0.15 mm. The annular jet ring is located in the middle of the cylinder wall of the main combustion chamber, with 8 jet holes, the hole diameter is set to 0.5 mm, and the hydrogen injection velocity is set to 30 m / s; The vortex control valve is installed at the top of the main combustion chamber, and the valve opening adjustment range is set to 0-30°.

9. The methanol-diesel-hydrogen multi-fuel adaptive power coupling system for inland waterway vessels according to claim 8, characterized in that, An engine crankshaft position sensor is installed on the engine body. The engine crankshaft position sensor controls the fuel injection timing. Diesel is injected 15° before the piston compression stroke top dead center, and hydrogen is injected 3° after the diesel injection. For every 200 r / min increase in engine speed, the diesel injection advance angle increases by 1° crankshaft angle, and the hydrogen injection delay angle decreases by 0.5° crankshaft angle.

10. The methanol-diesel-hydrogen multi-fuel adaptive power coupling system for inland waterway vessels according to any one of claims 1 to 5, characterized in that, The entire process safety protection subsystem includes gas sensors, ventilation fans, audible and visual alarms, explosion-proof cameras, temperature control components, and safety valves; The gas sensor is installed along the methanol and hydrogen delivery pipelines. The detection limit for methanol is 500 ppm and the detection limit for hydrogen is 1000 ppm. When a leak is detected, the corresponding fuel shut-off valve is closed, the ventilation fan is started, and the audible and visual alarm is triggered. The explosion-proof camera is located in the hydrogen storage tank area; The temperature control component is used to monitor the exhaust temperature of the engine block. When the temperature exceeds 600°C, the diesel supply is reduced by 10% and the cooling water flow rate is increased. When the temperature reaches 650°C, an emergency shutdown is triggered. The safety valve is installed in the hydrogen production subsystem. When the gas pressure is higher than 1 MPa, it automatically activates to release pressure, and the released gas is introduced into the combustion chamber for combustion.

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