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CN-121993289-A - Jet ignition method and system for precombustion chamber of methanol ammonia hydrogen fuel marine engine

CN121993289ACN 121993289 ACN121993289 ACN 121993289ACN-121993289-A

Abstract

The invention discloses a jet ignition method and a jet ignition system for a precombustion chamber of a methanol ammonia hydrogen fuel marine engine, which relate to the field of ship power and comprise a fuel supply module, wherein the fuel supply module comprises a methanol injector, an ammonia injector, a hydrogen injector and a multi-stage fuel heating device; the jet ignition method and the jet ignition system for the engine precombustion chamber of the methanol ammonia hydrogen fuel ship adopt three fuels of methanol, ammonia and hydrogen, fully utilize the characteristics of different fuels, have wide methanol sources, are easy to store and transport, do not generate carbon dioxide after being combusted as zero-carbon fuel, have the characteristics of high energy density and clean combustion, can adjust the temperature of the fuel to 200-450 ℃, not only utilize the waste heat of the engine, but also can flexibly adjust the fuel through electric heating, ensure that the fuel is at proper injection and combustion temperature, improve the atomization effect and combustion efficiency of the fuel, enable the three fuels to play roles in a synergistic way, and realize high-efficiency utilization.

Inventors

  • WANG YUCHUN
  • SUN ZEGANG
  • ZHONG HONGMIN
  • JIN XIN

Assignees

  • 四川轻化工大学

Dates

Publication Date
20260508
Application Date
20260203

Claims (8)

  1. 1. A methanolic ammonia hydrogen fuelled marine engine prechamber jet ignition system comprising: a fuel supply module comprising a methanol injector, an ammonia injector, a hydrogen injector, and a multi-stage fuel heating device; The pre-combustion chamber jet ignition module comprises a pre-combustion chamber, a main combustion chamber, a spark plug, a secondary fuel injector and a jet hole optimizing structure, wherein the volume of the pre-combustion chamber is not more than 5% of the volume of the main combustion chamber, and the pre-combustion chamber is provided with the jet hole with the diameter of 3.5 mm; the main control module comprises an ECU, an air inlet pressure sensor, an air inlet temperature sensor, an ammonia supply pressure sensor and an ammonia supply temperature sensor, wherein the ECU is used for dynamically adjusting a fuel injection strategy and an ignition moment according to the rotation speed, the load and the excessive air coefficient of an engine; And the emission control module comprises an EGR system, an SCR catalyst and an FTIR on-line monitoring device.
  2. 2. The jet ignition system of the methanol ammonia hydrogen fuel marine engine prechamber is characterized in that a ceramic coating is coated on the inner wall of a jet hole, the spark plug and the auxiliary fuel injector are coaxially arranged in the prechamber, the spray holes of the auxiliary fuel injector are arranged corresponding to the spark plug, a cooling water channel is arranged at the bottom of the prechamber, the temperature of the wall surface of the prechamber is maintained at 300-500 ℃ through engine waste heat or an electric heating device, and the ceramic coating is made of high-temperature-resistant oxidized ceramic and is used for reducing quenching effect of the wall surface of the jet hole.
  3. 3. The jet ignition system of the precombustion chamber of the methanol ammonia hydrogen fuel marine engine, which is disclosed in claim 1, is characterized in that the methanol injector is a piezoelectric crystal injector which is arranged on the side wall of a main combustion chamber, the injection angle is consistent with the direction of air inlet vortex, the ammonia injector is a liquid ammonia low-pressure injector which is arranged in an air inlet manifold and is provided with a first heater for gasifying and preheating liquid ammonia, the hydrogen injector is arranged at the top of the precombustion chamber, the injection amount of hydrogen is controlled through an electromagnetic valve, and the injection amount range is 5% -15% of the total fuel heat.
  4. 4. The jet ignition system of the precombustion chamber of the methanol ammonia hydrogen fuel marine engine, according to claim 1, wherein the fuel injection time of the main control module meets the conditions that the methanol injection time is 300-240 degrees CA before the compression stroke top dead center, the injection pulse width is 400-800 mu s, the ammonia injection time is 45-30 degrees CA before the compression stroke top dead center, the injection angle forms a 15-degree included angle with the air inlet vortex direction, the hydrogen injection time is 25-15 degrees CA before the compression stroke top dead center, and the injection pressure is 5-10MPa.
  5. 5. The jet ignition system of the methanol ammonia hydrogen fuel marine engine prechamber of claim 1, wherein the jet time of the auxiliary fuel injector is 180-40 degrees CA before the top dead center of the compression stroke, the jet ignition time of the prechamber jet ignition module is 10-3 degrees CA before the top dead center of the compression stroke, the ignition energy is more than or equal to 80mJ, and the working temperature of the SCR catalyst is 250-450 ℃.
  6. 6. The jet ignition system of the methanol ammonia hydrogen fuel marine engine prechamber according to claim 1 is characterized in that the EGR system is used for recycling 10% -25% of exhaust gas, mixing the exhaust gas with pressurized air and then entering an intake manifold, the SCR catalyst is made of Cu-Zeolite base materials and is arranged at the rear end of the exhaust manifold, the FTIR on-line monitoring device is used for detecting NOx concentration in real time and feeding data back to the ECU, and the data fed back by the FTIR on-line monitoring device are used for adjusting EGR rate and hydrogen injection quantity by the ECU.
  7. 7. A methanol ammonia hydrogen fuelled marine engine prechamber jet ignition system as in claim 1 wherein said multi-stage fuel heating means comprises a second heater and an ammonia hydrogen production means for regulating the fuel temperature to 200-450 ℃, wherein said second heater comprises an electric heater and a waste heat recovery heater, and wherein said ammonia hydrogen production means is a catalytic reforming hydrogen production means.
  8. 8. A method of igniting a jet ignition system of a methanol ammonia hydrogen fuelled marine engine as claimed in any one of claims 1 to 7 comprising the steps of: The method comprises the steps of firstly, preprocessing fuel, gasifying liquid ammonia into ammonia gas through a first heater, mixing the ammonia gas with pressurized air in an air inlet manifold, preheating methanol to 40-60 ℃ through a second heater, spraying the preheated methanol into a main combustion chamber through a piezoelectric crystal fuel injector, and simultaneously cracking the liquid ammonia by an ammonia hydrogen production device to generate hydrogen gas which is stored in a high-pressure hydrogen tank for standby; Step two, stratified injection control, wherein the initial stage of the compression stroke is 300-240 degrees CA before the top dead center, the main combustion chamber injects methanol, the middle stage of the compression stroke is 45-30 degrees CA before the top dead center, the air inlet manifold injects ammonia, the final stage of the compression stroke is 25-15 degrees CA before the top dead center, and then the precombustion chamber injects hydrogen; The jet flow flame enters the main combustion chamber through a jet hole with the diameter of 3.5mm to ignite the methanol/ammonia mixed gas, and the ECU dynamically adjusts the ignition moment and the fuel injection quantity according to feedback data of a pressure sensor in a cylinder so as to control the combustion phase to be 5-15 CA after the upper dead center; and fourthly, after the exhaust is treated, the exhaust is recovered by an EGR system and enters an SCR catalyst bed, then the concentration of NOx and N2O is detected in real time by an FTIR on-line monitoring device, and the ECU realizes cooperative control by adjusting the EGR rate, the hydrogen injection amount and the exhaust temperature.

Description

Jet ignition method and system for precombustion chamber of methanol ammonia hydrogen fuel marine engine Technical Field The invention relates to a ship power technology, in particular to a jet ignition method and a jet ignition system for a precombustion chamber of a methanol ammonia hydrogen fuel ship engine. Background At present, although the technology of jet ignition of a precombustion chamber and the application of methanol, ammonia and hydrogen fuel in an engine are studied, in the field of marine engines, most of the existing marine engine fuel systems are designed aiming at single fuel, and efficient utilization and flexible switching of various clean fuels are difficult to realize, so that the method and the system for jet ignition of the precombustion chamber of the marine engine of the methanol ammonia hydrogen fuel are provided. Disclosure of Invention The invention aims to provide a jet ignition method and a jet ignition system for a methanol ammonia hydrogen fuel marine engine, which aim to solve the problems that most of the existing marine engine fuel systems are designed aiming at single fuel, and high-efficiency utilization and flexible switching of various clean fuels are difficult to realize. In order to achieve the purpose, the invention provides the technical scheme that the jet ignition system of the precombustion chamber of the methanol ammonia hydrogen fuel marine engine comprises the following components: a fuel supply module comprising a methanol injector, an ammonia injector, a hydrogen injector, and a multi-stage fuel heating device; The pre-combustion chamber jet ignition module comprises a pre-combustion chamber, a main combustion chamber, a spark plug, a secondary fuel injector and a jet hole optimizing structure, wherein the volume of the pre-combustion chamber is not more than 5% of the volume of the main combustion chamber, and the pre-combustion chamber is provided with the jet hole with the diameter of 3.5 mm; the main control module comprises an ECU, an air inlet pressure sensor, an air inlet temperature sensor, an ammonia supply pressure sensor and an ammonia supply temperature sensor, wherein the ECU is used for dynamically adjusting a fuel injection strategy and an ignition moment according to the rotation speed, the load and the excessive air coefficient of an engine; And the emission control module comprises an EGR system, an SCR catalyst and an FTIR on-line monitoring device. The spark plug and the auxiliary fuel injector are coaxially arranged in the pre-combustion chamber, the spray holes of the auxiliary fuel injector are arranged corresponding to the spark plug, a cooling water channel is arranged at the bottom of the pre-combustion chamber, the temperature of the wall surface of the pre-combustion chamber is maintained at 300-500 ℃ through engine waste heat or an electric heating device, and the ceramic coating is made of high-temperature resistant oxidized ceramic and is used for reducing quenching effect of the wall surface of the jet flow hole. The methanol injector is a piezoelectric crystal injector which is arranged on the side wall of the main combustion chamber, the injection angle of the methanol injector is consistent with the direction of air inlet vortex, the ammonia injector is a liquid ammonia low-pressure injector which is arranged in an air inlet manifold and is provided with a first heater for gasifying and preheating liquid ammonia, the hydrogen injector is arranged on the top of the precombustion chamber, the injection quantity of hydrogen is controlled through an electromagnetic valve, and the injection quantity range is 5% -15% of the total fuel heat. Further, the fuel injection time of the main control module meets the conditions that the methanol injection time is 300-240 degrees CA before the compression stroke top dead center, the injection pulse width is 400-800 mu s, the ammonia injection time is 45-30 degrees CA before the compression stroke top dead center, the injection angle forms an included angle of 15 degrees with the air inlet vortex direction, the hydrogen injection time is 25-15 degrees CA before the compression stroke top dead center, and the injection pressure is 5-10MPa. Further, the injection time of the auxiliary fuel injector is 180-40 degrees CA before the compression stroke top dead center, the jet ignition time of the pre-combustion chamber jet ignition module is 10-3 degrees CA before the compression stroke top dead center, the ignition energy is more than or equal to 80mJ, and the working temperature of the SCR catalyst is 250-450 ℃. The system comprises an Exhaust Gas Recirculation (EGR) system, an exhaust gas recirculation (SCR) system, an on-line monitoring device and an on-line monitoring device, wherein the EGR system is used for recycling 10% -25% of exhaust gas, mixing the exhaust gas with pressurized air and then entering an intake manifold, the SCR catalyst is made of a Cu-Zeolite base material and is