JP7397695B2 - Determination device, ship-to-land communication system, and determination method - Google Patents

Description

The present disclosure relates to a determination device that determines the possibility of air leakage in an air spring included in a valve operating device for an exhaust valve of a marine two-stroke engine, a ship-to-land communication system equipped with the same, and a determination method.

Conventionally, a marine two-stroke engine includes a cylinder that forms a combustion chamber, an exhaust valve that opens and closes an exhaust port provided in the cylinder, and a valve train that drives the exhaust valve. Patent Document 1 discloses a marine two-stroke engine equipped with this type of exhaust valve and valve operating device.

The valve train for a marine two-stroke engine disclosed in Patent Document 1 includes a hydraulically driven valve actuator. The valve actuator includes a hydraulic cylinder and a piston inserted into the hydraulic cylinder, and an exhaust valve is connected to the piston via a spindle. A pressure chamber is formed in the hydraulic cylinder on one side relative to the piston, through which hydraulic oil flows in and out. By communicating the pressure chamber with the high pressure supply conduit, high pressure hydraulic oil flows into the pressure chamber and moves the exhaust valve in the valve opening direction. The exhaust valve is biased toward closing by an air spring. The air spring consists of an air cylinder and a spring piston that slides within the air cylinder, and forms a spring chamber filled with air that is compressed and expanded by movement of the spring piston. The spring piston is connected to the spindle of the exhaust valve. When the pressure in the pressure chamber of the hydraulic cylinder is released, the air in the spring chamber expands and the exhaust valve moves in the valve closing direction.

Japanese Patent Application Publication No. 11-30112

If air leakage occurs in the air spring provided in the above-mentioned valve operating system, phenomena such as the exhaust valve not being properly seated or the valve closing timing being delayed occur. This lowers the compression pressure, leading to poor combustion.

When air leaks from the air spring, the in-cylinder pressure waveform changes from normal. Therefore, the possibility of air leakage from the air spring can be estimated based on the in-cylinder pressure waveform. However, there are many other factors that change the cylinder pressure waveform other than air leakage from the air spring. For example, changes in the in-cylinder pressure waveform are also caused by malfunction of the sliding part of the exhaust valve, malfunction of the fuel valve, combustion fluctuations due to fluctuations in air supply conditions, and the like. In other words, it is difficult to determine whether there is air leakage from the air spring just by monitoring the in-cylinder pressure waveform.

On the other hand, in order to detect air leakage from the air spring, it is conceivable to provide a sensor that directly detects the pressure in the spring chamber of the air spring. However, since the pressure in the spring chamber constantly fluctuates, it is difficult to use the pressure in the spring chamber to determine whether there is air leakage from the air spring.

The present invention has been made in view of the above, and proposes a technique for more accurately determining the presence or absence of air leakage from an air spring provided in a valve operating device for an exhaust valve.

A determination device according to one aspect of the present invention determines the possibility of air leakage in an air spring included in a valve operating device for an exhaust valve provided in each of the plurality of cylinders in a marine two-stroke engine having a plurality of cylinders. A determination device that determines,
an in-cylinder pressure measuring device that measures in-cylinder pressure in relation to a crank angle for each of the plurality of cylinders;
Obtaining measured values representing a state of the marine two-stroke engine, and at least one type of first group of state values that deny the possibility of the air leak, and/or at least one that affirms the possibility of the air leak. a state value calculator that calculates one type of second group state value;
a determination device that acquires the cylinder pressure, the state value of the first group, and/or the state value of the second group, and determines the possibility of the air leak;
The determination device determines that the in-cylinder pressure when the piston in the cylinder is located at the top dead center is the compression pressure, and that the difference between a predetermined compression pressure reference value and the compression pressure is a predetermined compression pressure threshold. When the state value of the first group is larger, the possibility of the air leak is determined to be lower, and/or the larger the state value of the second group is, the higher the possibility of the air leak is determined to be. It is characterized by being configured as follows.

Furthermore, the ship-to-land communication system according to one aspect of the present invention includes:
The determination device;
A data transmission device installed on the ship,
Equipped with a management device installed on land,
The determination device is provided in the management device,
The cylinder pressure measuring device and the state value calculator are provided in the ship,
The data transmitting device is configured to transmit data of the in-cylinder pressure, the state value of the first group, and the state value of the second group to the management device via satellite communication. It is said that

Further, in a marine two-stroke engine having a plurality of cylinders, the determination method according to one aspect of the present invention provides a method for determining the possibility of air leakage in an air spring included in a valve operating device for an exhaust valve provided in each of the plurality of cylinders. A determination method for determining gender using a computer ,
Obtaining the in-cylinder pressure measured in relation to the crank angle for each of the plurality of cylinders,
at least one type of first group of status values that negates the possibility of air leakage calculated from measured values representing the status of the marine two-stroke engine; and/or measurements representing the status of the marine two-stroke engine. obtaining at least one type of second group status value that affirms the possibility of the air leak calculated from the value ;
The in-cylinder pressure when the piston in the cylinder is located at the top dead center is defined as compression pressure, and when the difference between a predetermined compression pressure reference value and the compression pressure exceeds a predetermined compression pressure threshold, The possibility of air leakage is determined to be low as the state value of the first group is large, and/or the possibility of air leakage is determined to be high as the state value of the second group is large. .

According to the determination device, ship-land communication device, and determination method configured as described above, when the compression pressure decreases, the larger the state value of the first group is, the lower the possibility of air leakage from the air spring is determined to be. Alternatively/in addition, it is determined that the larger the state value of the second group is, the higher the possibility of air leakage from the air spring is. In this way, in addition to the compression pressure, the possibility of air leakage is determined by taking into account at least one of the state values of the first group and the state values of the second group. Since the decrease in air is excluded, the presence or absence of air leakage can be determined more accurately.

According to the present invention, it is possible to propose a technique for more accurately determining the presence or absence of air leakage from an air spring included in a valve operating device for an exhaust valve.

FIG. 1 is a block diagram showing a schematic configuration of a ship-to-land communication system to which a determination device according to an embodiment of the present invention is applied. FIG. 2 is a diagram showing the configuration of the fuel supply device. FIG. 3 is a diagram showing the configuration of the valve train. FIG. 4 is a diagram showing an example of an in-cylinder pressure waveform for one combustion cycle of the engine. FIG. 5 is a block diagram showing the configuration of the determination device. FIG. 6 is a block diagram showing the configuration of the management device. FIG. 7 is a diagram showing a compression pressure design value curve representing a compression pressure design value corresponding to the engine load. FIG. 8 is a chart showing the relationship between the difference between the compression pressure reference value and the compression pressure and the condition index. FIG. 9 is a chart showing the relationship between the amount of decrease in exhaust valve stroke and the first condition index. FIG. 10 is a chart showing the relationship between the amount of delay in the exhaust valve closing timing and the second state index. FIG. 11 is a chart showing the relationship between the amount of increase in the erosion volume and the third state index. FIG. 12 is a chart showing the relationship between the amount of increase in exhaust gas temperature and the fourth state index. FIG. 13 is a chart showing the relationship between the amount of increase in scavenging chamber temperature and the fifth state index.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings. In addition, below, the same reference numerals are given to the same or equivalent element throughout all the figures, and the redundant explanation will be omitted.

[Overall configuration of ship-to-land communication system 1]
FIG. 1 is a block diagram showing a schematic configuration of a ship-to-land communication system 1 to which a determination device 300 according to an embodiment of the present invention is applied. As shown in FIG. 1, the ship-to-land communication system 1 in this embodiment includes a shipboard system 2 provided on a ship 4 and a management device 3 provided on land. The ship 4 includes an engine system 5 that is a main propulsion engine.

[Configuration of engine system 5]
The engine system 5 includes a large two-stroke engine (hereinafter simply referred to as "engine 10") and a supercharger 20 that compresses air supplied to the engine 10. Note that the engine 10 may be a power generation engine for the ship 4.

Engine 10 has a plurality of cylinders 11 (only one is shown in FIG. 1). The engine 10 according to the present embodiment is a uniflow two-cycle engine, and has a scavenging port 12 formed at the bottom of the cylinder 11 and an exhaust port 13 formed at the top of the cylinder 11. A piston 14 that slides across the scavenging port 12 is provided within the cylinder 11 . A combustion chamber 50 is formed by the piston 14, cylinder 11, and the like. The piston 14 is connected to a crankshaft 18 via a connecting rod 17.

A fuel injection valve 15 is provided at the top of the cylinder 11 . Fuel supplied from the fuel supply device 31 is blown out into the combustion chamber 50 through the fuel injection valve 15 . The fuel supply device 31 supplies pressurized fuel to the fuel injection valve 15 at a predetermined timing during the engine cycle and in an amount corresponding to the engine load.

FIG. 2 is a diagram showing the configuration of the fuel supply device 31. As shown in FIG. As shown in FIG. 2, the fuel supply device 31 includes a hydraulically driven fuel pump 34 and a fuel oil supply pipe 38 that supplies high-pressure fuel from the fuel pump 34 to the fuel injection valve 15. The fuel pump 34 includes a cylinder 340 and a piston 341 provided within the cylinder 340 so as to be able to reciprocate. A piston 341 within the cylinder 340 has a fuel chamber 342 on one side and a pressure chamber 343 on the other side. Fuel is supplied to the fuel chamber 342 from a fuel source (not shown). The pressure chamber 343 is connected to the high pressure pipe 36 via the control valve 37. High-pressure hydraulic oil compressed by a pump 47 is supplied to the high-pressure pipe 36 from a supply pipe 46 . The control valve 37 is between an ON state in which hydraulic fluid is allowed to flow from the high pressure pipe 36 into the pressure chamber 343 and an OFF state in which hydraulic fluid is prevented from flowing from the high pressure pipe 36 into the pressure chamber 343. Switch with . When the control valve 37 is OFF, the connection between the high pressure pipe 36 and the pressure chamber 343 is cut off, and the pressure chamber 343 is connected to the return pipe 35.

When the control valve 37 is turned ON and the high pressure pipe 36 and the pressure chamber 343 are connected, high pressure hydraulic oil flows from the high pressure pipe 36 into the pressure chamber 343, and the piston 341 is pushed down. On the other hand, when the control valve 37 is turned OFF and the return pipe 35 and the pressure chamber 343 are connected, hydraulic oil flows out from the pressure chamber 343 to the return pipe 35. In the fuel supply device 31, the operation amount (stroke amount) of the piston 341 is adjusted by the operation of the control valve 37, and the pressure of the fuel supplied to the fuel injection valve 15 is controlled by the operation amount of the piston 341. In this way, the amount of fuel injected from the fuel injection valve 15, the fuel injection pattern, and the fuel injection timing can be changed.

The exhaust port 13 is provided with an exhaust valve 16 that opens and closes the exhaust port 13 . The exhaust valve 16 is a poppet valve having a conical valve body 161. The exhaust valve 16 is driven to open and close by a valve train 32. FIG. 3 is a diagram showing the configuration of the valve train 32. As shown in FIG. The valve train 32 shown in FIG. 3 includes a hydraulically driven valve actuator 61 and a drive actuator 63. The valve actuator 61 includes a hydraulic cylinder 610 and a piston 611 provided within the hydraulic cylinder 610 so as to be able to freely reciprocate. A valve body 161 is fixed to the piston 611 via a spindle 162. A pressure chamber 613 is formed on one side via a piston 611 within the hydraulic cylinder 610 . The drive actuator 63 includes a hydraulic cylinder 630 and a drive piston 631 provided within the hydraulic cylinder 630 so as to be able to freely reciprocate. One side of the hydraulic cylinder 630 via the drive piston 631 serves as a hydraulic oil chamber 632, and the other side serves as a drive pressure chamber 633. The hydraulic oil chamber 632 is connected to the pressure chamber 613 of the valve actuator 61 via the oil passage 62. The drive pressure chamber 633 is connected to the high pressure pipe 49 via the control valve 64. The control valve 64 has two states: an ON state in which hydraulic fluid is allowed to flow from the high pressure pipe 49 into the drive pressure chamber 633, and an OFF state in which the flow of hydraulic fluid from the high pressure pipe 49 into the drive pressure chamber 633 is blocked. Switch between. When the control valve 64 is OFF, the connection between the high pressure pipe 49 and the drive pressure chamber 633 is cut off, and the drive pressure chamber 633 is connected to the return pipe 48 .

The valve train 32 includes an air spring 33 that biases the exhaust valve 16 in the valve closing direction. The air spring 33 includes an air cylinder 331 and a spring piston 332 provided within the air cylinder 331 so as to be able to freely reciprocate. A valve body 161 is fixed to the spring piston 332 via a spindle 162. A spring chamber 333 is formed on one side via a spring piston 332 within the air cylinder 331 . The spring chamber 333 is filled with air.

When the control valve 64 is turned on and the drive pressure chamber 633 is connected to the high pressure pipe 49, high pressure liquid flows into the drive pressure chamber 633, and the drive piston 631 moves in the direction of compressing the hydraulic oil in the hydraulic oil chamber 632. Moving. As a result, the pressure in the pressure chamber 613 of the valve actuator 61 communicating with the hydraulic oil chamber 632 increases, and the piston 611 moves in the valve opening direction (downward), thereby opening the exhaust port 13. In the air spring 33, the spring piston 332 moves integrally with the exhaust valve 16 in the valve opening direction, and the air in the spring chamber 333 is compressed.

On the other hand, when the control valve 64 is turned off and the drive pressure chamber 633 is connected to the return pipe 48, the pressure in the drive pressure chamber 633 is released. The exhaust valve 16 and the piston 611 move in the valve closing direction (upward) due to the bias of the air spring 33, and hydraulic oil flows from the pressure chamber 343 to the hydraulic oil chamber 632, and from the drive pressure chamber 633 to the return pipe 48. flows out. As a result, the exhaust valve 16 is seated on the valve seat and the exhaust port 13 is closed.

When the exhaust port 13 is opened, combustion gas flows out from the combustion chamber 50 to the exhaust pipe 26. Combustion gas (ie, exhaust gas) is sent to supercharger 20 through exhaust pipe 26 . The supercharger 20 includes a turbine 21 and a compressor 22 connected to the turbine 21 by a rotating shaft 23. The turbine 21 is rotated by exhaust gas supplied from the cylinder 11 through an exhaust pipe 26. The compressor 22 rotates integrally with the turbine 21, introduces air from the outside, and performs adiabatic compression. The compressed air is supplied to the engine 10 via the scavenging pipe 24 and the scavenging chamber 25.

FIG. 4 is a diagram showing an example of an in-cylinder pressure waveform for one combustion cycle of the engine 10. The cylinder pressure waveform is a cylinder pressure-crank angle relationship diagram (trend diagram) obtained from detected values of the cylinder pressure and crank angle. During one rotation of the crankshaft 18, the piston 14 performs an upward stroke and a downward stroke. The operation of the exhaust valve 16 is controlled based on the detected value of the crank angle. The exhaust port 13 is opened at a predetermined crank angle in the latter half of the downward stroke, and closed at a predetermined crank angle in the early stage of the upward stroke. Further, the scavenging port 12 is opened at a crank angle a predetermined period after the exhaust port 13 opens in the latter half of the downward stroke, and is opened at a crank angle a predetermined period before the exhaust port 13 closes in the early stage of the upward stroke. Closed. At the beginning of the upward stroke, the combustion chamber 50 is scavenged (exhaust of combustion gas and intake of fresh air) while the piston 14 is rising, and at the latter stage of the upward stroke, fresh air is compressed while the piston 14 is rising. Ru. Immediately before the piston 14 reaches top dead center TDC, fuel is injected from the fuel injection valve 15 into the compressed air, and spontaneously ignites due to the temperature rise due to compression. In the downward stroke, the piston 14 descends due to combustion (explosion) of the fuel, and in the latter half of the downward stroke, the exhaust port 13 is opened and combustion gas is exhausted from the combustion chamber 50.

[Configuration of onboard system 2]
The onboard system 2 includes an engine control device 60 that controls the engine system 5 and a data collection device 6 that collects data representing the state of the engine system 5. The data collected by the data collection device 6 includes engine load data, cylinder pressure data, crank angle detection data, fuel injection timing data, exhaust valve position data, exhaust gas temperature data, scavenging chamber temperature data, and the like. The stroke and closing timing of the exhaust valve 16 can be determined from the exhaust valve position, and the data collected by the data collection device 6 further includes exhaust valve stroke data and exhaust valve closing timing data. Note that the engine control device 60 acquires fuel control valve working pressure data, exhaust control valve working pressure data, fuel injection amount data, etc. in order to control the engine system 5.

As shown in FIG. 5, the data collection device 6 includes an engine load detector 51, an in-cylinder pressure sensor 52, an exhaust gas thermometer 53, an exhaust valve position detector 55, a crank angle detector 56, and a scavenging chamber thermometer 57. The device is electrically connected to the device, and the detected values are obtained from these devices.

The data collection device 6 measures engine load data. The engine load data may be obtained based on data detected by the engine load detector 51. For example, when the output shaft rotation speed of the engine 10 is used as an index of engine load, the engine load detector 51 may be a rotation speed sensor provided on the output shaft of the engine 10. For example, the output required of the engine 10 (eg, throttle value) may be used as an index of engine load. For example, when the rotating shaft 23 of the supercharger 20 is used as an index of engine load, the engine load detector 51 may be a rotation speed sensor provided on the rotating shaft 23 of the supercharger 20. For example, when the fuel injection amount and engine rotation speed are used as indicators of engine load, the engine load detector 51 includes an injection amount detector 54 provided in the fuel pump 34 and an engine rotation speed detector (not shown) provided in the engine 10. omitted).

The data collection device 6 has an in-cylinder pressure measuring device 65. The cylinder pressure sensor 52 is provided in each cylinder 11 of the engine 10 and detects the pressure within the combustion chamber 50. The crank angle detector 56 is provided on the crankshaft 18 and detects the crank angle (ie, the rotational position of the crankshaft 18). The crank angle detector 56 transmits, for example, a crank pulse signal for calculating the crank angle to the cylinder pressure measuring device 65. The cylinder pressure measuring device 65 acquires the detected cylinder pressure and crank angle at a predetermined sampling period, and measures the cylinder pressure by associating the cylinder pressure with information on the crank angle at the time of measuring the cylinder pressure. Generate data. For example, the cylinder pressure measuring device 65 assumes that the crank angle is 0° when the piston 14 is at the top dead center TDC position, and changes the cylinder pressure in an angular range from -180° to 180° based on that. get.

The data collection device 6 generates exhaust valve stroke data based on the detected value of the exhaust valve position detector 55. The exhaust valve position detector 55 is provided in the valve train 32 and detects the displacement (ie, valve position) of the exhaust valve 16. In this embodiment, a non-contact type sensor is used as the exhaust valve position detector 55 to detect the displacement of the piston 611 that reciprocates integrally with the valve body 161 or its accessories. The data collection device 6 measures exhaust valve position data in which the position of the exhaust valve 16 detected by the exhaust valve position detector 55 is associated with information on the crank angle at the time of measuring the position of the exhaust valve 16. The displacement width of the exhaust valve position is the exhaust valve stroke. The data collection device 6 generates exhaust valve stroke data based on the exhaust valve position data. The exhaust valve closing timing θc is the crank angle when the exhaust valve is closed. The data collection device 6 generates exhaust valve closing timing data from the exhaust valve position data. However, the exhaust valve closing timing θc can also be specified using cylinder pressure data. In this case, the crank angle when the cylinder pressure starts to rise during the upward stroke of the piston 14 is the exhaust valve closing timing θc.

The data collection device 6 generates exhaust gas temperature data based on the detected value of the exhaust gas thermometer 53. The exhaust gas thermometer 53 is provided between the exhaust port 13 of each cylinder 11 and the exhaust pipe 26, and detects the temperature Te of the exhaust gas flowing from the combustion chamber 50 to the exhaust pipe 26.

The data collection device 6 generates scavenging chamber temperature data based on the detected value of the scavenging chamber thermometer 57. The scavenging chamber thermometer 57 is provided within the scavenging chamber 25 and detects the scavenging chamber temperature Ts, which is the temperature of the air within the scavenging chamber 25.

The onboard system 2 further includes a data transmission device 7 that generates a data transmission signal, and an outboard communication section 8 that transmits the generated data transmission signal to the management device 3 via satellite communication. The data transmission device 7 acquires predetermined data from the engine control device 60 and/or the data collection device 6 and generates a data transmission signal to be transmitted to the management device 3. The data transmitting device 7 may be constituted by a known computer device. The data transmitting device 7 and the outboard communication section 8 are connected via an inboard LAN 9 so as to be able to send and receive signals. The outboard communication section 8 includes a server capable of transmitting e-mails, for example. Various data servers, arithmetic devices, input devices, display devices, etc. (all not shown) may be connected to the ship's LAN 9. The data transmission signal transmitted from the outboard communication section 8 is transmitted by satellite communication via the communication satellite 40.

[Configuration of management device 3]
The management device 3 may be provided with a satellite antenna 41 capable of receiving data transmission signals by satellite communication. In addition to this, or in place of this, the data transmission signal is once received by another satellite antenna 42 installed on land, and the data is transmitted from the satellite antenna 42 to the management device 3 via a communication network 43 such as the Internet. A transmission signal may be transmitted.

FIG. 6 is a block diagram showing the configuration of the management device 3. As shown in FIG. As shown in FIG. 6, the management device 3 includes a calculation device 30, an output device 27 such as a printer, display, warning light, or buzzer, an input device 28 such as a keyboard or pointing device, and a large-capacity storage device 29. Equipped with The arithmetic device 30 is a so-called computer, and includes a processor 301 , a memory 302 , a communication section 304 , an input/output section 303 , and an interface 305 . An output device 27 , an input device 28 , and a storage device 29 are connected to the arithmetic device 30 via an interface 305 .

The management device 3 stores various data included in the data transmission signal acquired via the communication unit 304 in the storage device 29. A database storing various data transmitted from the onboard system 2 is constructed in the storage device 29 . The storage device 29 stores, for example, engine load data, cylinder pressure data, fuel injection timing data, exhaust valve position data, exhaust gas temperature data, scavenging chamber temperature data, exhaust valve stroke data, and exhaust valve closing timing data. A stored database may be constructed.

[Configuration of determination device 300]
The ship-to-land communication system 1 includes a determination device 300 that determines whether or not there is an air leak from an air spring 33 included in a valve train 32 included in the engine 10 . The determining device 300 includes a determining device 3A, an in-cylinder pressure measuring device 65 that measures the in-cylinder pressure in each of the plurality of cylinders 11 in relation to a crank angle, and acquires a measured value representing the state of the engine 10 to detect air leakage. A first group state value calculator 66 calculates a first group state value that negates the possibility of air leakage, and a second group state value calculator 66 that obtains a measured value representing the state of the engine 10 to confirm the possibility of air leakage and a second group of state value calculators 67 that calculate state values. The state value calculators 66 and 67 are composed of at least one arithmetic unit.

The determiner 3A is configured in the management device 3. A determination program is stored in the memory 302 of the management device 3. The management device 3 functions as a determiner 3A when the processor 301 reads and executes the determination program.

The cylinder pressure measuring device 65, the first group of state value calculators 66, and the second group of state value calculators 67 are configured in the data collection device 6.

The first group of state value calculators 66 acquire measured values representing the state of the engine 10 and calculate at least one type of first group of state values that deny the possibility of air leakage from the air spring 33. The first group of state values includes at least one of the following: exhaust valve stroke reduction amount ΔS, exhaust gas temperature Te increase amount ΔTe, erosion volume increase amount, and scavenging chamber temperature Ts increase amount ΔTs. It will be done. The above measurement values include measurement data for calculating the state value of the first group. Such measured values include exhaust valve stroke data based on the detected value of the exhaust valve position detector 55, exhaust gas temperature data based on the detected value of the exhaust gas thermometer 53, and exhaust gas temperature data based on the detected value of the scavenging chamber thermometer 57. Among the base scavenging chamber temperature data, data corresponding to the first group of state values is included.

The second group state value calculator 67 calculates at least one type of second group state value that affirms the possibility of air leakage from the air spring 33. Note that the second group of state values includes a delay amount Δθc of the exhaust valve closing timing θc. The above measurement values include measurement data for calculating the state value of the second group. Such measured values include an engine load sensor based on the detected value of the engine load detector 51, cylinder pressure data based on the detected value of the in-cylinder pressure sensor 52, and exhaust gas data based on the detected value of the exhaust valve position detector 55. The valve closing timing data includes data corresponding to the second group of state values.

The determiner 3A determines the possibility of air leakage in the air spring 33 by acquiring the cylinder pressure, the first group state value, and the second group state value. The determination process performed by the determiner 3A will be described in detail below.

The determiner 3A extracts the compression pressure P _comp from the cylinder pressure data and monitors the value. The compression pressure P _comp is the in-cylinder pressure when the piston 14 in the cylinder 11 is located at the top dead center TDC (see FIG. 4). The determiner 3A compares the measured compression pressure P _comp with a predetermined compression pressure reference value. If the compression pressure P _comp is equal to or higher than the compression pressure reference value, no air leakage occurs from the air spring 33, but if the compression pressure P _comp becomes smaller than the compression pressure reference value, air leakage from the air spring 33 may occur. It can be assumed that there is a sex.

In the above, the compression pressure reference value may be an average value of the compression pressure P _comp of a predetermined number of cycles immediately before the target cycle of the target cylinder 11. Further, the compression pressure reference value may be an average value of compression pressures P _comp measured at an engine load equivalent to the target cycle. Alternatively, the compression pressure reference value may be an average value of compression pressures P _comp measured in a plurality of cylinders 11 included in the engine 10 in the same cycle as the target cycle. Further, the compression pressure reference value may be a compression pressure design value associated with the engine load in the target cylinder 11. FIG. 7 is a diagram showing a compression pressure design value curve representing a compression pressure design value corresponding to the engine load. In the compression pressure design value curve, the compression pressure design value increases as the engine load increases. A compression pressure design value _curve as shown in FIG _. (ratio) may be used to determine a compression pressure design value corresponding to the measured engine load, which may be used as the compression pressure reference value. The scavenging pressure _Ps is the in-cylinder pressure during the scavenging stroke. Further, the compression pressure reference value may be a compression pressure determined from the measured scavenging pressure _Ps using a designed compression pressure/scavenging pressure ratio.

The determiner 3A performs a determination process on the condition that the compression pressure P _comp is smaller than the compression pressure reference value, and the difference ΔPc between the compression pressure reference value and the compression pressure P _comp is larger than a predetermined compression pressure threshold Ac. Start.

The determiner 3A that has started the determination process calculates the condition index F and at least one type among the first condition index R ₁ to the fifth condition index R ₅ . The condition index to be adopted may be determined depending on the structure of the engine 10. Although one type of condition index may be employed, the accuracy of the determination improves as more types of condition indexes are employed.

Condition indices R ₁ to R ₅ are the first group of condition indexes that indicate factors that reduce the possibility of air leaks occurring (negative factors) and factors that increase the possibility that air leaks occur (positive factors). It can be classified into the second group of condition indexes shown below. It is desirable that the condition indices R ₁ to R ₅ employed in the determination include at least one type of first group condition index and at least one type of second group condition index.

[Condition index F]
The condition index F represents the degree of decrease in the compression pressure P _comp . FIG. 8 is a chart showing the relationship between the difference ΔPc between the compression pressure reference value and the compression pressure P _comp and the condition index F, in which the vertical axis represents the condition index F and the horizontal axis represents the difference ΔPc. The condition index F(ΔPc) is a function of the difference ΔPc. The condition index F (ΔPc) is zero until the difference ΔPc reaches the compression pressure threshold Ac, and increases as the difference ΔPc increases when the difference ΔPc exceeds the compression pressure threshold Ac.

[Negative element: first state index R ₁ ]
When the exhaust valve operation is inhibited due to dirt or damage to the exhaust valve sliding part and the exhaust valve stroke is reduced, the compression pressure P _comp may be reduced. If the exhaust valve stroke has decreased, the cause of the decrease in the compression pressure P _comp may be other than air leakage from the air spring 33 . Therefore, the amount of decrease ΔS in the exhaust valve stroke from the predetermined exhaust valve stroke reference value is used as the state value of the first group, and the first condition index _R1 , which decreases as the amount of decrease ΔS increases, is the state value of the first group. Used as a condition index.

The first group of state value calculators 66 uses the exhaust valve stroke data to determine the amount of decrease ΔS in the exhaust valve stroke from the exhaust valve stroke reference value. The exhaust valve stroke reference value may be an average value of exhaust valve strokes of a predetermined number of cycles immediately before the target cycle of the target cylinder 11. Further, the exhaust valve stroke reference value may be an average value of exhaust valve strokes measured at an engine load equivalent to the target cycle. Alternatively, the exhaust valve stroke reference value may be an average value of exhaust valve strokes measured in a plurality of cylinders 11 included in the engine 10 in the same cycle as the target cycle.

The determiner 3A determines the first state index _R1 based on the exhaust valve stroke reduction amount ΔS. FIG. 9 is a chart showing the relationship between the exhaust valve stroke reduction amount ΔS and the first condition index R ₁ , where the vertical axis represents the first condition index R ₁ and the horizontal axis represents the exhaust valve stroke reduction amount ΔS. represents. The relationship between the exhaust valve stroke reduction amount ΔS and the first state index _R1 is stored in advance in the determiner 3A. The first state index R ₁ (ΔS) is a constant value (for example, 1) when the exhaust valve stroke reduction amount ΔS is less than or equal to the stroke threshold As, and is a constant value (for example, 1) when the exhaust valve stroke reduction amount ΔS exceeds the stroke threshold As (i.e. , when the exhaust valve stroke becomes smaller than the stroke threshold As) sharply decreases to almost zero.

[Affirmative element: second state index R ₂ ]
If there is a delay in the exhaust valve closing timing θc of the target cylinder 11, there is a high possibility that the decrease in the detected compression pressure _Pcomp is caused by air leakage from the air spring 33. Therefore, the delay amount Δθc of the exhaust valve closing timing θc from the predetermined exhaust valve closing timing reference value is used as the second group of state values, and the second state index _R2 , which increases as the delay amount Δθc increases, is used as the second state value. It is used as a condition index for the second group.

The second group of state value calculators 67 uses the exhaust valve closing timing data to determine a delay amount Δθc of the exhaust valve closing timing θc from a predetermined exhaust valve closing timing reference value. The exhaust valve closing timing reference value may be an average value of exhaust valve closing timings θc measured in the same cycle as the target cycle in a plurality of cylinders 11 included in the engine 10.

The determiner 3A determines the second state index _R2 based on the delay amount Δθc of the exhaust valve closing timing θc. FIG. 10 is a chart showing the relationship between the delay amount Δθc of the exhaust valve closing timing _θc and the second state index R2, where the vertical axis represents the second state index _R2 , and the horizontal axis represents the delay amount Δθc of the exhaust valve closing timing θc. It represents the amount of delay Δθc. The relationship between the delay amount Δθc of the exhaust valve closing timing θc and the second state index R2 is stored in advance in the determiner 3A. The second state index R ₂ (Δθc) is zero when the delay amount Δθc is below the delay threshold Aθc, and increases as the delay amount Δθc increases when the delay amount Δθc exceeds the delay threshold Aθc.

[Negative element: third state index R ₃ ]
If erosion occurs in the elements forming the combustion chamber 50, such as the cylinder cover, the contact surface of the exhaust valve 16, and the top of the piston crown, the volume of the combustion chamber 50 will become larger than the designed value. An increase in the volume of the combustion chamber 50 may cause a decrease in the compression pressure P _comp . Therefore, the amount of increase in the erosion volume from zero (i.e., the erosion volume) is used as the state value of the first group, and the third condition index decreases as the increase in the erosion volume increases. R ₃ is used as the condition index of the first group.

During inspection, the state of corrosion of the cylinder cover forming the combustion chamber 50, the contact surface of the exhaust valve 16, the top of the piston crown, etc. is visually confirmed. If erosion is found in the members forming the combustion chamber 50 by visual inspection, the volume of erosion is measured. The erosion volume is stored in advance in the determiner 3A, and is updated every time an inspection is performed.

The determiner 3A determines the third condition index _R3 based on the amount of increase in the erosion volume. FIG. 11 is a chart showing the relationship between the amount of increase in the erosion volume and the third condition index _R3 , in which the vertical axis represents the third condition index _R3 , and the horizontal axis represents the erosion volume. The relationship between the amount of increase in the erosion volume and the third state index _R3 is stored in advance in the determiner 3A. When the volume reduced by erosion (erosion volume) is zero (that is, when there is no erosion), the third state index _R3 is 1. The third state index _R3 decreases stepwise (or continuously) as the etched volume increases.

[Negative element: fourth state index R ₄ ]
When gas leaks from the combustion chamber 50 due to a seat defect in the exhaust valve 16, the compression pressure _Pcomp decreases. On the other hand, if a seat failure occurs in the exhaust valve 16, the combustion gas in the combustion chamber 50 leaks downstream of the exhaust port 13, and the exhaust gas temperature Te detected by the exhaust gas thermometer 53 increases. Therefore, the amount of increase ΔTe in the exhaust gas temperature Te from the predetermined exhaust gas temperature reference value is used as the state value of the first group, and the fourth condition index _R4 , which decreases as the amount of increase ΔTe increases, is used as the state value of the first group. It is used as a condition index.

The first group of state value calculators 66 uses the exhaust gas temperature data to determine the amount of increase ΔTe in the exhaust gas temperature Te from a predetermined exhaust gas temperature reference value. The exhaust gas temperature reference value may be an average value of exhaust gas temperatures Te measured in a plurality of cylinders 11 included in the engine 10 in the same cycle as the target cycle. Alternatively, the exhaust gas temperature reference value may be an average value of the exhaust gas temperatures Te measured over a predetermined period at the exhaust pipe 26 connected to the target cylinder 11.

The determiner 3A determines the fourth state index _R4 based on the amount of increase ΔTe in the exhaust gas temperature Te. FIG. 12 is a chart showing the relationship between the amount of increase ΔTe in exhaust gas temperature Te and the fourth state index _R4 , where the vertical axis represents the fourth state index _R4 , and the horizontal axis represents the amount of increase in exhaust gas temperature Te. It represents ΔTe. The relationship between the amount of increase ΔTe in the exhaust gas temperature Te and the fourth state index _R4 is stored in advance in the determiner 3A. The fourth state index R ₄ (ΔTe) is a constant value (for example, 1) when the amount of increase ΔTe of exhaust gas temperature Te is less than or equal to a predetermined threshold value ATe, and when the amount of increase ΔTe exceeds the threshold value ATe, the amount of increase is It decreases as ΔTe increases.

[Negative element: 5th state index R ₅ ]
When gas leaks from the combustion chamber 50 due to a seal failure of a piston ring (not shown) fitted to the piston 14, the compression pressure _Pcomp decreases. On the other hand, if a sealing failure occurs in the piston ring, combustion gas in the combustion chamber 50 leaks into the scavenging chamber 25, causing an increase in the temperature of the scavenging chamber 25. Therefore, the amount of increase ΔTs in the scavenging chamber temperature Ts from the predetermined reference value of the scavenging chamber temperature is used as the state value of the first group, and the fifth condition index _R5 , which decreases as the amount of increase ΔTs increases, is used as the state value of the first group. It is used as a condition index.

The first group of state value calculators 66 use the scavenging chamber temperature data to determine the amount of increase ΔTs in the scavenging chamber temperature Ts from a predetermined scavenging chamber temperature reference value. The scavenging chamber temperature reference value may be an average value of the scavenging chamber temperatures Ts measured in a plurality of cylinders 11 included in the engine 10 in the same cycle as the target cycle. Alternatively, the scavenging chamber temperature reference value may be an average value of the scavenging chamber temperatures Ts measured over a predetermined period in the scavenging chamber 25 connected to the target cylinder 11.

The determiner 3A determines the fifth state index _R5 based on the increase amount ΔTs of the scavenging chamber temperature Ts. FIG. 13 is a chart showing the relationship between the amount of increase ΔTs in the scavenging chamber temperature Ts and the fifth condition index _R5 , where the vertical axis represents the fifth condition index _R5 , and the horizontal axis represents the amount of increase in the scavenging chamber temperature Ts. It represents ΔTs. The relationship between the amount of increase ΔTs in the scavenging chamber temperature Ts and the fifth state index _R5 is stored in advance in the determiner 3A. The fifth state index R ₅ (ΔTs) is a constant value (for example, 1) when the increase amount ΔTs is less than or equal to the threshold value ATs, and decreases as the increase amount ΔTs increases when the increase amount ΔTs exceeds the threshold value ATs. do.

[Evaluation function C]
The determiner 3A evaluates the possibility of air leakage in the air spring 33 based on the evaluation index calculated using the evaluation function C. The evaluation function C is an arithmetic expression that multiplies the sum of the condition index of the first group and the condition index of the second group by the condition index F. At least one of the first group of condition indices and the second group of condition indices may be weighted based on the magnitude of influence on the evaluation index. By using such an evaluation index, the determiner 3A determines that the state value of the first group is the same when the difference ΔPc between the predetermined compression pressure reference value and the compression pressure _P The larger the state value of the second group is, the lower the possibility of air leakage is judged to be, and/or the larger the state value of the second group is, the higher the possibility of air leakage is judged to be.

In this embodiment, the determiner 3A uses the condition index F and the first condition index R ₁ to the fifth condition index R ₅ calculated as described above, and the influence index α ₁ to α ₅ stored in advance, An evaluation index is calculated using the obtained evaluation function C. The evaluation function C is expressed by the following equation (1).
C=F×R...Formula (1)
(However, R=α ₁・R ₁ +α ₂・R ₂ +α ₃・R ₃ +α ₄・R ₄ +α ₅・R ₅ )

In the above, α ₁ to α ₅ are influence indices indicating the degree of influence of each condition index R ₁ to R ₅ on the determination of the possibility of air leakage. The influence indices α ₁ to α ₅ represent the weights of each state index R ₁ to R ₅ relative to other state indices. The values of the influence indices α ₁ to α ₅ are not particularly limited, but are set to, for example, α ₁ :α ₂ :α ₃ :α ₄ :α ₅ =25:20:5:25:25, with the whole being 100. . Note that the influence indices α ₁ to α ₅ can be set to different ratios depending on the characteristics, specifications, years of use, etc. of the engine 10. Furthermore, the influence indices α ₁ to α ₅ may be set based on the results of machine learning (supervised learning). Furthermore, in the evaluation function C, the influence indices α ₁ to α ₅ may not be used (ie, α ₁ =α ₂ =α ₃ =α ₄ =α ₅ =1).

The larger the evaluation index calculated by the determiner 3A using the evaluation function C as described above becomes, the higher the possibility of air leakage in the air spring 33 becomes. If the evaluation index calculated using the evaluation function C exceeds a predetermined criterion, the determiner 3A determines that there is a high possibility of air leakage in the air spring 33, and issues a predetermined notification. The predetermined notification may be performed, for example, through the output device 27 (for example, a display, a warning light, a buzzer, etc.) of the management device 3, or by transmitting an abnormality notification signal from the management device 3 to the ship 4. This may be done using a display device, a warning light, a buzzer, etc., provided in 4.

As described above, the ship-to-land communication system 1 according to the present embodiment includes the data transmitting device 7 provided on the ship 4, the management device 3 provided on land, and the determination device 300. The determining device 300 includes a determining device 3A provided in the management device 3, and an in-cylinder pressure measuring device 65 and state value calculators 66 and 67 provided in the ship 4. The data transmitting device 7 is configured to transmit the in-cylinder pressure, data on the first group of state values, and data on the second group of state values to the management device 3 via satellite communication. Note that in the above embodiment, the determiner 3A is provided on land, but the determiner 3A may be provided in the ship 4.

The cylinder pressure measuring device 65 measures the cylinder pressure of the cylinder 11 of the engine 10 in relation to the crank angle, and generates cylinder pressure measurement data. The condition value calculators 66 and 67 acquire measured values representing the condition of the engine 10 and calculate at least one type of first group of condition values that deny the possibility of air leakage and/or the possibility of air leakage. At least one type of second group state value that is affirmative is calculated. The determiner 3A determines the possibility of air leakage from the air spring 33 by acquiring the cylinder pressure, the first group of state values, and/or the second group of state values. Here, the determiner 3A determines that when the difference ΔPc between the predetermined compression pressure reference value and the compression pressure P _comp exceeds the predetermined compression pressure threshold Ac, the larger the state value of the first group is, the more likely air leakage is. is determined to be low, and/or the possibility of air leak is determined to be high as the state value of the second group is large.

Similarly, the determination method according to the present embodiment detects the in-cylinder pressure for each of the plurality of cylinders 11, obtains a measured value representing the state of the engine 10, and uses at least one type of determination method to deny the possibility of air leakage. A first group of state values and/or at least one type of second group of state values that affirm the possibility of air leakage are calculated, and the difference ΔPc between a predetermined compression pressure reference value and a compression pressure threshold Ac is calculated. When a predetermined compression pressure threshold Ac is exceeded, the larger the state value of the first group is, the lower the possibility of air leakage is determined, and/or the larger the state value of the second group is, the lower the possibility of air leakage is determined. Judge highly.

According to the above-described determination device 300 and determination method, when the compression pressure P _comp decreases, the larger the state value of the first group is, the lower the possibility of air leakage from the air spring 33 is determined to be. Alternatively/in addition, it is determined that the larger the state value of the second group is, the higher the possibility of air leakage from the air spring 33 is. In this way, in addition to the compression pressure P _comp , the possibility of air leakage is determined by taking into account the state values of the first group and the state values of the second group, so that the compression pressure P _comp due to causes other than air leakage Since the decrease in air is excluded, the presence or absence of air leakage can be determined more accurately.

In the above, at least one of the state values of the first group and the state values of the second group is used for the determination, but from the viewpoint of making a more reliable determination, the state values of the first group and the state values of the second group are It is desirable that both values be used for determination. Therefore, in the determination device 300 according to the present embodiment, the state value calculators 66 and 67 include a first group state value calculator 66 that calculates the first group state values, and a first group state value calculator 66 that calculates the second group state values. and a second group of state value calculators 67. Then, when the difference ΔPc between the compression pressure reference value and the compression pressure P _comp exceeds the compression pressure threshold Ac, the determiner 3A determines that the larger the state value of the first group is, the lower the possibility of air leakage is, The larger the state value of the second group is, the higher the possibility of air leakage is judged to be.

In this way, the determination can be made based on both the first group of state values, which are determining factors that reduce the possibility of air leakage in the air spring 33, and the second group of state values, which are determining factors that increase the possibility. This allows a more reliable determination to be made.

In the determination device 300 according to the present embodiment, the determination device 3A uses a condition index F that increases with an increase in the difference ΔPc between the compression pressure reference value and the compression pressure P _comp , and an increase in the condition value of the first group. The state index of the first group (R ₁ , R ₃ , R ₄ , R ₅ ) decreases as the state value of the second group increases, and the state index of the second group (R ₂ ) increases as the state value of the second group increases. is calculated using an evaluation function C that is obtained by multiplying the sum of the condition index of the first group (R ₁ , R ₃ , R ₄ , R ₅ ) and the condition index of the second group (R ₂ ) by the condition index F. , configured to determine the possibility of an air leak.

Similarly, in the determination method according to the present embodiment, the condition index F increases as the difference ΔPc between the compression pressure reference value and the compression pressure P _comp increases, and the condition index F decreases as the condition value of the first group increases. The state index (R ₁ , R ₃ , R ₄ , R ₅ ) of the first group and the state index (R ₂ ) of the second group that increases as the state value of the second group increases, and Using evaluation function C, which is the sum of the condition index of the group (R ₁ , R ₃ , R ₄ , R ₅ ) and the condition index of the second group (R ₂ ), multiplied by the condition index F, the possibility of air leakage is determined. Determine gender.

According to the above-described determination device 300 and determination method, the higher the possibility of air leakage in the air spring 33, the larger the evaluation index obtained by the evaluation function C, so that the possibility of air leakage can be easily visualized. can.

In the determination device 300 and determination method described above, at least one of the first group of condition indexes and the second group of condition indexes may be weighted based on the magnitude of influence on the determination of air leakage.

In this way, the possibility of air leakage is more accurately represented by the evaluation function C by weighting the condition indexes individually based on the magnitude of their influence on the determination of air leakage, instead of uniformly adding them together.

In the determination device 300 and determination method described above, the measured value may include the exhaust valve stroke, and the first group of state values may include the amount of decrease ΔS in the exhaust valve stroke from a predetermined exhaust valve stroke reference value.

If an abnormality occurs in the sliding portion of the exhaust valve 16, the exhaust valve operation may be inhibited, the exhaust valve stroke may decrease, and the compression pressure P _comp may decrease. Therefore, by including the exhaust valve stroke reduction amount ΔS in the first group of state values, it is possible to know whether an abnormality in the sliding portion of the exhaust valve 16 is involved in the reduction in the measured compression pressure P _comp . be able to.

In the above determination device 300 and determination method, the measured value includes the exhaust valve closing timing θc, and the second group of state values includes the delay amount Δθc of the exhaust valve closing timing θc from a predetermined exhaust valve closing timing reference value. good.

If air leakage occurs in the air spring 33, the exhaust valve closing timing will be delayed, and the compression pressure _Pcomp will decrease. In this way, air leakage from the air spring 33 can directly affect the delay in the exhaust valve closing timing. Therefore, by including the amount of delay in the exhaust valve closing timing in the second group of state values, it is possible to more clearly determine whether or not there is a possibility that air leakage from the air spring 33 is involved in the decrease in the measured compression pressure _Pcomp . can be known.

In the above determination device 300 and determination method, the measured value includes the erosion volume of the combustion chamber forming member in the cylinder 11, and the state value of the first group is the amount of increase in the erosion volume from no erosion (i.e., the erosion volume ) may be included.

Since the volume of the combustion chamber 50 increases as the erosion volume increases, the compression pressure P _comp decreases. Therefore, by including the increase in the erosion volume in the state values of the first group, it is possible to know whether erosion of the combustion chamber forming member in the cylinder 11 is involved in the decrease in the measured compression pressure P _comp . be able to.

In the determination device 300 and determination method, the measured value includes the exhaust gas temperature Te from the cylinder 11, and the first group of state values includes the increase amount ΔTe in the exhaust gas temperature Te from the predetermined exhaust gas temperature reference value. It's okay to stay.

When a seat defect occurs in the exhaust valve 16, the exhaust gas temperature Te increases. On the other hand, a defective seat in the exhaust valve 16 causes a decrease in the compression pressure P _comp . Therefore, by including the increase amount ΔTe in the exhaust gas temperature Te in the first group of state values, it is possible to know whether or not a seat defect in the exhaust valve 16 is involved in the decrease in the measured compression pressure P _comp . can.

In the determination device 300 and determination method described above, the measured value includes the scavenging chamber temperature Ts of the scavenging chamber 25 in which the air supplied to the cylinder 11 is stored, and the state value of the first group is determined from a predetermined scavenging chamber temperature reference value. may include the amount of increase ΔTs in the scavenging chamber temperature Ts.

When a seal failure occurs in the piston 14, the scavenging chamber temperature Ts increases. On the other hand, a seal failure in the piston 14 causes a decrease in the compression pressure P _comp . Therefore, by including the amount of increase ΔTs in the scavenging chamber temperature Ts in the first group of state values, it is possible to know whether the seal failure of the piston 14 is involved in the decrease in the measured compression pressure P _comp . .

Note that both the first group of state values and the second group of state values described above can be easily estimated using instruments conventionally installed in the engine system 5 of the ship 4. That is, it is possible to determine whether the cause of the decrease in the compression pressure P _comp is air leakage in the air spring 33 or another factor using easily measurable state values. Therefore, the possibility of air leakage in the air spring 33 can be determined with a simple configuration.

Although the preferred embodiments of the present invention have been described above, the present invention may include modifications to the specific structure and/or functional details of the above embodiments without departing from the spirit of the present invention. . The configurations of the above-described ship-to-land communication system 1 and determination device 300 can be modified as follows, for example.

For example, in the above-described embodiment, a mode is exemplified in which all of the first state index R ₁ to fifth state index R ₅ are used in the evaluation function C, but the present invention is not limited to this. That is, it is sufficient that at least one of the five condition indexes R ₁ to R ₅ is used, and there may be a condition index that is not used. Note that depending on the case, any of the influence indexes α ₁ to α ₅ may be set to 0 to eliminate the influence of the corresponding state indexes R ₁ to R ₅ on the evaluation function C. For example, the condition index with the largest influence index (any one of R ₁ , R ₄ , and R ₅ ) in the condition index of the first group, which is a negative element, and the condition index with the largest influence index in the second group, which is a positive element. The evaluation function C may be calculated using the state index (R ₂ ) having the largest index.

Further, in the above embodiment, the data transmission signal generated by the data transmission device 7 is transmitted to the outboard communication section 8, and the outboard communication section 8 transmits the data to the management device 3 on land via satellite communication. is illustrated, but the data transmitting device 7 may directly transmit data to the management device 3 on land via satellite communication. That is, the data transmitting device 7 may include an outboard communication section 8 that performs satellite communication.

Further, in the embodiment described above, an example is given in which the determining device 3A is provided in the management device 3 on land, but the determining device 3A may be provided in land equipment other than the management device 3. Alternatively, the determiner 3A may be provided on the ship, such as a computing unit for determination processing connected to the data transmitting device 7 or the ship's LAN 9, for example.

Further, the engine 10 to be determined is not particularly limited as long as it is a combustion engine provided in the ship 4. For example, the engine 10 may include engines 10 for various uses, such as a main propulsion engine, various auxiliary machines, and an internal combustion engine for inboard power generation.

1 : Ship-land communication system 2 : Shipboard system 3 : Management device 3A : Judgment device 4 : Ship 5 : Engine system 6 : Data collection device 7 : Data transmission device 10 : Engine 11 : Cylinder 12 : Scavenging port 13 : Exhaust port 14: Piston 15: Fuel injection valve 16: Exhaust valve 18: Crankshaft 20: Supercharger 24: Scavenging pipe 25: Scavenging chamber 26: Exhaust pipe 31: Fuel supply device 32: Valve train 33: Air springs 36, 49 : High pressure pipe 40 : Communication satellite 41, 42 : Satellite antenna 50 : Combustion chamber 51 : Engine load detector 52 : In-cylinder pressure sensor 53 : Exhaust gas thermometer 54 : Injection amount detector 55 : Exhaust valve position detector 56 : Crank angle detector 57 : Scavenging chamber temperature meter 60 : Engine control device 61 : Valve actuator 65 : In-cylinder pressure measuring device 66 : First group state value calculator 67 : Second group state value calculator 300 : Judgment device 331: Air cylinder 332: Spring piston 333: Spring chamber

Claims (18)

In a marine two-stroke engine having a plurality of cylinders, a determination device for determining the possibility of air leakage in an air spring included in a valve operating device for an exhaust valve provided in each of the plurality of cylinders, the determination device comprising:
an in-cylinder pressure measuring device that measures in-cylinder pressure in relation to a crank angle for each of the plurality of cylinders;
Obtaining measured values representing a state of the marine two-stroke engine, and at least one type of first group of state values that deny the possibility of the air leak, and/or at least one that affirms the possibility of the air leak. a state value calculator that calculates one type of second group state value;
a determination device that acquires the cylinder pressure, the state value of the first group, and/or the state value of the second group, and determines the possibility of the air leak;
The determination device determines that the in-cylinder pressure when the piston in the cylinder is located at the top dead center is the compression pressure, and that the difference between a predetermined compression pressure reference value and the compression pressure is a predetermined compression pressure threshold. When the state value of the first group is larger, the possibility of the air leak is determined to be lower, and/or the larger the state value of the second group is, the higher the possibility of the air leak is determined to be. It is configured as follows.
Judgment device. The state value calculator includes a first group of state value calculators that calculate the first group of state values, and a second group of state value calculators that calculates the second group of state values,
The determining device determines that the possibility of the air leak is lower as the state value of the first group is larger when the difference between the compression pressure reference value and the compression pressure exceeds the compression pressure threshold; The larger the state value of the second group, the higher the possibility of the air leak is determined.
The determination device according to claim 1. The determiner is
Determining a condition index that increases with an increase in the difference between the compression pressure reference value and the compression pressure,
Determine the state index of the first group that decreases as the state value of the first group increases, and/or the state index of the second group that increases as the state value of the second group increases,
The possibility of air leakage is determined using an evaluation function obtained by multiplying the sum of the condition index of the first group and the condition index of the second group by the condition index.
The determination device according to claim 1 or 2. At least one of the first group of condition indexes and the second group of condition indexes is weighted based on the magnitude of influence on the air leak determination.
The determination device according to claim 3. The measured value includes an exhaust valve stroke, and the first group of state values includes a decrease in the exhaust valve stroke from a predetermined exhaust valve stroke reference value.
The determination device according to any one of claims 1 to 4. The measured value includes an exhaust valve closing timing, and the second group of state values includes a delay amount of the exhaust valve closing timing from a predetermined exhaust valve closing timing reference value.
The determination device according to any one of claims 1 to 5. The measured value includes an erosion volume of the combustion chamber forming member in the cylinder, and the first group of state values includes an increase in the erosion volume from no erosion.
The determination device according to any one of claims 1 to 6. The measured value includes an exhaust gas temperature from the cylinder, and the first group of state values includes an increase in the exhaust gas temperature from a predetermined exhaust gas temperature reference value.
The determination device according to any one of claims 1 to 7. The measured value includes the scavenging air chamber temperature of the scavenging air chamber in which air supplied to the cylinder is stored, and the first group of state values includes an increase in the scavenging air chamber temperature from a predetermined scavenging chamber temperature reference value. include,
The determination device according to any one of claims 1 to 8. A determination device according to any one of claims 1 to 9,
A data transmission device installed on the ship,
Equipped with a management device installed on land,
The determination device is provided in the management device,
The cylinder pressure measuring device and the state value calculator are provided in the ship,
The data transmitting device is configured to transmit data of the in-cylinder pressure, the first group state value, and the second group state value to the management device via satellite communication.
Ship-to-shore communication system. In a marine two-stroke engine having a plurality of cylinders, a determination method that uses a computer to determine the possibility of air leakage in an air spring included in a valve operating device for an exhaust valve provided in each of the plurality of cylinders, the method comprising:
Obtaining the in-cylinder pressure measured in relation to the crank angle for each of the plurality of cylinders,
at least one type of first group of status values that negates the possibility of air leakage calculated from measured values representing the status of the marine two-stroke engine; and/or measurements representing the status of the marine two-stroke engine. obtaining at least one type of second group status value that affirms the possibility of the air leak calculated from the value ;
The in-cylinder pressure when the piston in the cylinder is located at the top dead center is defined as compression pressure, and when the difference between a predetermined compression pressure reference value and the compression pressure exceeds a predetermined compression pressure threshold, The larger the state value of the first group is, the lower the possibility of the air leak is determined, and/or the larger the state value of the second group is, the higher the possibility of the air leak is determined.
Judgment method. a condition index that increases as the difference between the compression pressure reference value and the compression pressure increases, a condition index of the first group that decreases as the condition value of the first group increases, and a condition index of the second group that increases as the difference between the compression pressure reference value and the compression pressure increases; Find the state index of the second group that increases as the state value increases,
determining the possibility of the air leak using an evaluation function obtained by multiplying the sum of the condition index of the first group and the condition index of the second group by the condition index;
The determination method according to claim 11. At least one of the first group of condition indexes and the second group of condition indexes is weighted based on the magnitude of influence on the air leak determination.
The determination method according to claim 12. The measured value includes an exhaust valve stroke, and the first group of state values includes a decrease in the exhaust valve stroke from a predetermined exhaust valve stroke reference value.
The determination method according to any one of claims 11 to 13. The measured value includes an exhaust valve closing timing, and the second group of state values includes a delay amount of the exhaust valve closing timing from a predetermined exhaust valve closing timing reference value.
The determination method according to any one of claims 11 to 14. The measured value includes an erosion volume of the combustion chamber forming member in the cylinder, and the first group of state values includes an increase in the erosion volume from no erosion.
The determination method according to any one of claims 11 to 15. The measured value includes an exhaust gas temperature from the cylinder, and the first group of state values includes an increase in the exhaust gas temperature from a predetermined exhaust gas temperature reference value.
The determination method according to any one of claims 11 to 16. The measured value includes the scavenging air chamber temperature of the scavenging air chamber in which air supplied to the cylinder is stored, and the first group of state values includes an increase in the scavenging air chamber temperature from a predetermined scavenging chamber temperature reference value. include,
The determination method according to any one of claims 11 to 17.

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