Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D35/00—Controlling engines, dependent on conditions exterior or interior to engines, not otherwise provided for
  • F02D35/02—Controlling engines, dependent on conditions exterior or interior to engines, not otherwise provided for on interior conditions
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
  • F02B77/00—Component parts, details or accessories, not otherwise provided for
  • F02B77/08—Safety, indicating, or supervising devices
  • F02B77/089—Safety, indicating, or supervising devices relating to engine temperature
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01M—LUBRICATING OF MACHINES OR ENGINES IN GENERAL; LUBRICATING INTERNAL COMBUSTION ENGINES; CRANKCASE VENTILATING
  • F01M1/00—Pressure lubrication
  • F01M1/08—Lubricating systems characterised by the provision therein of lubricant jetting means
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01M—LUBRICATING OF MACHINES OR ENGINES IN GENERAL; LUBRICATING INTERNAL COMBUSTION ENGINES; CRANKCASE VENTILATING
  • F01M11/00—Component parts, details or accessories, not provided for in, or of interest apart from, groups F01M1/00 - F01M9/00
  • F01M11/10—Indicating devices; Other safety devices
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01P—COOLING OF MACHINES OR ENGINES IN GENERAL; COOLING OF INTERNAL-COMBUSTION ENGINES
  • F01P7/00—Controlling of coolant flow
  • F01P7/14—Controlling of coolant flow the coolant being liquid
  • F01P7/16—Controlling of coolant flow the coolant being liquid by thermostatic control
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D35/00—Controlling engines, dependent on conditions exterior or interior to engines, not otherwise provided for
  • F02D35/02—Controlling engines, dependent on conditions exterior or interior to engines, not otherwise provided for on interior conditions
  • F02D35/025—Controlling engines, dependent on conditions exterior or interior to engines, not otherwise provided for on interior conditions by determining temperatures inside the cylinder, e.g. combustion temperatures
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D35/00—Controlling engines, dependent on conditions exterior or interior to engines, not otherwise provided for
  • F02D35/02—Controlling engines, dependent on conditions exterior or interior to engines, not otherwise provided for on interior conditions
  • F02D35/025—Controlling engines, dependent on conditions exterior or interior to engines, not otherwise provided for on interior conditions by determining temperatures inside the cylinder, e.g. combustion temperatures
  • F02D35/026—Controlling engines, dependent on conditions exterior or interior to engines, not otherwise provided for on interior conditions by determining temperatures inside the cylinder, e.g. combustion temperatures using an estimation
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/22—Safety or indicating devices for abnormal conditions
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D45/00—Electrical control not provided for in groups F02D41/00 - F02D43/00
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01M—LUBRICATING OF MACHINES OR ENGINES IN GENERAL; LUBRICATING INTERNAL COMBUSTION ENGINES; CRANKCASE VENTILATING
  • F01M1/00—Pressure lubrication
  • F01M1/08—Lubricating systems characterised by the provision therein of lubricant jetting means
  • F01M2001/083—Lubricating systems characterised by the provision therein of lubricant jetting means for lubricating cylinders
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01M—LUBRICATING OF MACHINES OR ENGINES IN GENERAL; LUBRICATING INTERNAL COMBUSTION ENGINES; CRANKCASE VENTILATING
  • F01M11/00—Component parts, details or accessories, not provided for in, or of interest apart from, groups F01M1/00 - F01M9/00
  • F01M11/02—Arrangements of lubricant conduits
  • F01M2011/022—Arrangements of lubricant conduits for lubricating cylinders
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/008—Controlling each cylinder individually
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
  • Y02T10/00—Road transport of goods or passengers
  • Y02T10/10—Internal combustion engine [ICE] based vehicles
  • Y02T10/40—Engine management systems

Definitions

• the present invention relates to a method for detecting scuffing in a large two-stroke diesel engine, in particular to method for detecting a pre-scuffing condition, and an apparatus for detecting a pre-scuffing condition.
• Disturbances in the operation of large two-stroke diesel engines can lead to a reduction of power and to damage to the cylinders and pistons.
• the loss of power can be significant and if the engine has to be taken out of operation this can cause great problems, for example when the large two-stroke diesel engine is used as the main source of power in an oceangoing vessel.
• the piston rings and liner surface experience all three wear regimes as described by the Stribeck curve (figure 1) relating the (viscosity, load, speed) to the coefficient of friction. These three regimes are Boundary Lubrication, Mixed Lubrication and Hydrodynamic Lubrication. Hydrodynamic lubrication is the condition where there is full separation of the surfaces by an oil film. If the load is only partly carried by the oil film pressure and partly by contact by asperities the condition is named mixed lubrication. If the complete load is carried by asperities and the only separation is a molecular thin oil film, the condition is known as boundary lubrication.
• boundary lubrication is always present to a small extent around top dead Center (TDC) , where the velocity of the piston approaches zero. In case bore polish is taking place the amount of boundary lubrication may rise to a level where scuffing will occur.
• TDC top dead Center
• Temperature sensors in the cylinder liner wall near the top dead center are known to be used for detecting pre-scuffing events.
• the sensor is close to the local position of an adhesive contact (which may take place at a circumstantially different position than the position of the sensor or just above or under the sensor) will the local temperature increase that is caused by the adhesive contact result in an increase in temperature in the area of the sensor.
• the initial temperature increase will depend very much on the distance from the sensor to the position at which the adhesive contact takes place.
• Each sensor will always be only a single point of a larger running surface area.
• the adhesive contact takes place at a position somewhat removed from the sensor there will be a substantial delay in detecting the pre- scuffing event. This may be fatal since quick action is needed in order to save the cylinder liner.
• This object is achieved by providing a method for detecting a pre-scuffing condition in a large multi-cylinder turbocharged two-stroke diesel engine, said method comprising continuously or intermittently measuring the cylinder wall temperature for all cylinders, continuously or intermittently measuring the air temperature in the scavenging air box for all cylinders, determining on the basis of the combined information of cylinder wall temperature and the the air temperature in the scavenging air box if the temperature development of a cylinder indicates pre-scuffing events, and issuing a pre-scuffing alarm when pre-scuffing events have been determined.
• a method for detecting a pre-scuffing condition in a large multi-cylinder turbocharged two-stroke diesel engine comprising continuously or intermittently measuring the cylinder wall temperature for all cylinders, continuously or intermittently measuring the air temperature in the scavenging air box for all cylinders, determining on the basis of the combined information of cylinder wall temperature and the the air temperature in the scavenging air box if
• the method may further comprise continuously or intermittently measuring for all cylinders another cylinder related temperature at a position different from the cylinder wall and the air temperature in the scavenging air box, and carrying out said determination of pre-scuffing events on the basis of the combined information of the cylinder wall temperature, the air temperature in the scavenging air box and the other cylinder related temperatures .
• An alarm may be issued when the temperature of a cylinder fluctuates, and the peaks or the dips of the temperature fluctuations of the cylinder concerned are separated by a time span that falls in a predetermined range and the temperature difference between the peaks and the dips of the temperature fluctuation exceeds a predetermined threshold.
• a pre-scuffing alarm may be issued when at least a sequence with a predetermined number of the fluctuations occurs.
• the method may further comprise increasing cylinder lubrication level to a level above the level for normal operation for the cylinder for which the alarm is issued.
• the method may further comprise decreasing load level to a level below the level for a normal operation for the cylinder for which the alarm is issued.
• the a further cylinder related temperature that can be measured and used in the method is measured in a liquid medium.
• the other cylinder related temperature that is measured and used in the method may be the cylinder liner cooling water temperature .
• the other cylinder related temperatures measured may be a gaseous medium.
• the other cylinder related temperature may be the exhaust gas temperature of the cylinder concerned.
• figure 1 is a graph illustrating various lubrication regimes
• figure 2 is a detailed cross-sectional view of the top of a single cylinder of a multicylinder engine according to an embodiment of the invention
• figure 3 is a slightly less detailed view of the cylinder illustrated in figure 2
• figure 4 is a diagrammatic overview of the cylinders, the injection system, the cylinder lubrication system, the temperature sensing system and the electronic control system of an engine according to an embodiment of the invention
• figures 5 to 8 are graphs illustrating different cylinder related temperature developments of a cylinder showing pre- scuffing events .
• Figure 1 illustrates the so called Stribeck curve.
• the piston rings and liner surface experience all three wear regimes as described by this curve relating the (viscosity, load, speed) to the coefficient of friction.
• These thre regimes are Boundary Lubrication, Mixed Lubrication and Hydrodynamic Lubrication.
• Hydrodynamic lubrication is the condition where there is full separation of the surfaces by an oil film. If only partly of the load is carried by the oil film pressure and partly by contact by asperities the condition is named mixed lubrication. If the complete load is carried by asperities and the only separation is molecular thin oil film, the condition is known as boundary lubrication.
• boundary lubrication is always present to a small extent around top dead Center (TDC) , where the velocity of the piston is approaching zero. In case bore polish is taking place the amount of boundary lubrication may rise to a level where scuffing will occur.
• TDC top dead Center
• Figure 2 illustrates one of the cylinders 10 of a large multicylinder two-stroke diesel engine of the crosshead type.
• a piston 12 moves up and down in the cylinder 10.
• the top of the cylinder is covered by a cylinder cover 14.
• the cylinder cover 14 is provided with an exhaust valve 16 and with fuel injectors 18.
• Temperature sensors 20 and 20' are provided in the area where the movement of the piston 12 is reversed, the so- called Top Dead Center (TDC) (i.e. the upper region of the cylinders).
• the temperature sensors 20,20' are located in the cylinder liner wall, and connected to an electronic control system ECS of the engine (figure 3) via signal cables 22.
• the temperature sensors 20,20' measure the cylinder wall temperature near the top of the cylinder and the signal of the temperature sensors is transferred by the data cables 22 to the electronic control system ECS in which they are processed by a processor.
• there are two diametrically opposite temperature sensors 20,20' In the shown embodiment there are two diametrically opposite temperature sensors 20,20'. However, it would also be possible to use only a single temperature sensor 20 per cylinder or to use more than two temperature sensors per cylinder that are distributed along the circumference of the cylinder.
• a temperature sensor 23 placed in the exhaust valve housing measures the temperature of the exhaust gases that leave the cylinder.
• a data cable 25 connects the temperature sensor 23 to the electronic control system ECS.
• Cylinder lubricator ports 26 are also provided along the circumference of the cylinder. Typically three to ten cylinder lubrication ports 26 are provided for each cylinder, although, mainly depending on cylinder bore other numbers of cylinder lubrication ports could be used.
• the cylinder lubrication ports 26 are provided with a cylinder oil pump 24 associated with each cylinder.
• the cylinder oil pump 24 adjusts the dosage of the cylinder oil to the operating conditions of the engine. During normal operation the dosage is set to be no more than adequate since cylinder oil is relatively expensive. The dosage will be influenced by the fuel quality and be higher when low-quality fuel with a high sulfur content is used and depends on the load and running speed of the engine or on the load of a specific cylinder.
• Figure 3 shows further temperature sensors that are associated with each of the cylinders for measuring the a cylinder related temperature at various positions around the cylinder so that better and more information can be obtained for timely and correctly detecting pre-scuffing events .
• a temperature sensor 30 measures the cylinder liner cooling jacket temperature, preferably at the outlet pipe of the cylinder liner cooling water jacket.
• the signal of the temperature sensor 30 is transferred by the data cable 32 to the electronic control system ECS.
• the cooling water sensor 30 will react instantly in case of any local excessive development of heat due to the large effect of the increased friction coefficient during pre-scuffing events. This heat development will affect the temperature consistently, regardless of the position of the contact damage in the upper part of the liner.
• the temperature increase can though be rather small, and therefore the temperature gradient in an embodiment also used by the processor for detecting the trigger conditions .
• a temperature sensor 50 measures the cylinder cooling oil temperature, preferably at the outlet conduit of the cylinder liner cooling oil.
• the signal of the temperature sensor 50 is transferred by the data cable 52 to the electronic control system ECS.
• the piston cooling oil sensor 50 will react instantly in case of any local excessive development of heat due to the large effect of an adhesive contact between parts during pre-scuffing events. This heat development will affect the temperature consistently, regardless of the position of the contact damage in the upper part of the liner.
• the temperature development of the cylinder liner cooling water jacket of a cylinder is in an embodiment compared by the processor with the development of the average temperature of the cylinder liner cooling water jacket temperature of some or all of the other cylinders of the engine.
• the cylinder liner cooling water jacket of a cylinder is compared with the development of the average temperature of all of the other cylinders.
• a temperature sensor 34 measures the air temperature in the scavenge box, preferably in the scavenge box 5 at a position close to the scavenge ports.
• the signal of the temperature sensor 34 is transferred by a data cable 36 to the electronic control system ECS.
• ECS electronice control system
• FIG. 4 shows an engine according to an embodiment of the invention with five cylinders 10.
• the number of cylinders in this embodiment merely exemplary and invention could be used on multi-cylinder large two-stroke diesel engines with any other number of cylinders.
• the temperature sensors 20, 20' , 30 and 34 of each of the cylinders 10 are connected via the signal cables 22, 32 and 36 to the electronic control system ECS of the engine.
• the cylinder lubrication pumps 24 of each of the cylinders 10 are also connected to the electronic control system. The same applies to be fuel injection system that is connected to the electronic control system ECS via signal cables 28.
• the cylinder wall temperature values, the cylinder jacket cooling water temperature and the air temperature in the scavenge box temperature supplied by the temperature sensors 20, 20', 30 and 34 of the cylinders 10 are measured and evaluated by the electronic control system ECS.
• the electronic control system ECS includes at least one processor that is configured to measure, analyze and process the cylinder related temperature signals.
• the measurement of the cylinder related temperatures may be intermittent, for example once every second or continuous.
• the processor analyzes the cylinder related temperatures of each of the cylinders 10 and analyzes the development of these on the cylinder related temperatures of each of the cylinders 10. Depending on the configuration, the processor will use two of the three available of the cylinder related temperatures.
• the three cylinder related temperatures being for example: cylinder wall temperature, cylinder jacket cooling water temperature and air temperature in the scavenge box.
• the processor issues a pre-scuffing alarm if any of the cylinders displays a temperature development that is typical for a pre-scuffing event.
• Figures 5 to 8 illustrate a typical pre-scuffing event followed by hypothetical scuffing event (indicated by the interrupted line in figure 5) for cylinder number four for various cylinder related temperatures.
• the pre-scuffing event commences by cylinder related temperature fluctuations.
• these fluctuations typically have a magnitude of fluctuation in the range between approximately 25 to approximately 65 C C.
• the cylinder jacket cooling water temperature also fluctuates (figure 6) with the same time interval between the peaks and dips as the cylinder wall temperature fluctuations, but the magnitude of the temperature fluctuations is much smaller (typically 1 to 5°C) than for the cylinder wall temperature fluctuations. This is due to the effect that the heat that is locally developed on the cylinder wall is distributed in the cooling water that has a high heat capacity.
• the jacket cooling temperature also has a tendency to gradually increase during a high friction condition event.
• the processor is in an embodiment configured to use the temperature gradient ⁇ t/ ⁇ T to improve the sensitiveness.
• the processor is configured to compare the temperature development of the cylinder jacket cooling water temperature with the development of the of the cylinder jacket cooling water temperature of the other cylinders, for example with the development of the average temperature of some or all the other cylinders.
• general changes in engine temperature, caused by changing conditions or such as occur after a cold start can be filtered out and will not erroneously be interpreted as fluctuations that relate to pre-scuffing events.
• a "relative" cylinder jacket cooling water temperature is obtained.
• the same procedure of comparing the temperature development to the temperature development of the other cylinders can be applied advantageously to the other cylinder related temperatures: cylinder wall temperature, air temperature in the scavenge box and exhaust gas temperature .
• the time span between the peaks of the cylinder related temperature fluctuations is typically in the range between approximately 6 to approximately 18 minutes.
• the period of time in which these events take place in figures 5 to 7 is labeled "high friction condition". In this state friction is increased but not to the level of friction that occurs during actual scuffing.
• the range of the magnitude of the cylinder wall temperature fluctuations may vary from engine to engine, may depend on engine size and design and can be determined empirically. This also applies to the range of the time span between the peaks of the temperature fluctuations.
• the magnitude for the temperature fluctuations is different for each of the four cylinder related temperatures.
• the temperature span for the cylinder wall temperature is typically in the magnitude of tens of degrees Celsius, whilst the temperature span for the cylinder jacket cooling water temperature is typically in the magnitude of a few degrees Celsius.
• the temperature of the air in the scavenge box does typically not fluctuate but increases gradually during a high friction condition.
• the temperature span for the air temperature in the scavenge box (figure 7) is typically 5 to 20 0 C from the start of the pre-scuffing event to actual scuffing.
• the temperature of the exhaust gases in the exhaust valve housing does typically not fluctuate but increases gradually during a high friction condition.
• the temperature span for the exhaust gas temperature in the exhaust valve housing (figure 8) is typically 10 to 40°C from the start of the pre-scuffing event to actual scuffing.
• the processor is configured to issue a pre-scuffing alarm when it has determined that the temperature fluctuations match the characteristic of a scuffing event.
• the processor may use two, three or if available more than three cylinder related temperatures.
• the processor determines whether the time span between the peaks of the fluctuation falls within the predetermined range and determines whether the temperature fluctuations exceed a predetermined magnitude.
• the processor is according to an embodiment configured to determine that the pre-scuffing event alarm is issued if only one of the available cylinder related temperatures fulfills the criteria matching a pre-scuffing event. According to another embodiment the processor is configured to determine that the pre-scuffing event alarm is issued if at least two of the available cylinder related temperatures fulfills the criteria for matching a pre-scuffing event.
• pre-scuffing event countermeasures may include increasing the cylinder lubrication oil dosage to a level above that of normal operation.
• the pre-scuffing event countermeasures may also include reducing the load on the cylinder for which the alarm has been issued. This countermeasure is effected by the electronic control system ECS by changing the amount and/or timing of the fuel injection via the respective signal cable 28. The pre-scuffing event countermeasures may also include reducing the engine speed.
• the processor is in an embodiment configured to apply a stricter control for the detection of a pre-scuffing event.
• the extra restriction is in the form of a minimum number of consecutive cylinder related temperature fluctuations that have to occur before an alarm is issued.
• a minimum number of consecutive fluctuations could be set to be two or three fluctuations (at least two of three peaks) .
• the invention has numerous advantages. Different embodiments or implementations may yield one or more of the following advantages. It should be noted that this is not an exhaustive list and there may be other advantages which are not described herein.
• One advantage of the invention is that it provides a reliable method for detecting pre- scuffing events.
• Another advantage of the invention is that it provides for automatic initiation of countermeasures upon detection of pre-scuffing events.
• a further advantage of the invention is that it allows the information in several cylinder related temperatures to be combined for determining the occurrence of pre-scuffing. It is yet another advantage of the present invention that it allows cylinder temperature information to be taken from different media, such as from a solid medium, a liquid medium and from a gaseous medium.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Combined Controls Of Internal Combustion Engines (AREA)
• Testing Of Engines (AREA)
• Lubrication Of Internal Combustion Engines (AREA)

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• 2008
  • 2008-04-17 JP JP2010507810A patent/JP4742178B2/ja active Active
  • 2008-04-17 WO PCT/EP2008/003094 patent/WO2009127234A1/en active Application Filing
  • 2008-04-17 CN CN2008800011598A patent/CN101652548B/zh active Active
  • 2008-04-17 KR KR1020097008947A patent/KR101106058B1/ko active IP Right Grant

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