CN116756621A - On-line diagnosis method for air inlet and outlet faults of engine - Google Patents
On-line diagnosis method for air inlet and outlet faults of engine Download PDFInfo
- Publication number
- CN116756621A CN116756621A CN202311008854.XA CN202311008854A CN116756621A CN 116756621 A CN116756621 A CN 116756621A CN 202311008854 A CN202311008854 A CN 202311008854A CN 116756621 A CN116756621 A CN 116756621A
- Authority
- CN
- China
- Prior art keywords
- engine
- valve
- key information
- exhaust
- faults
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims abstract description 44
- 238000003745 diagnosis Methods 0.000 title claims abstract description 18
- 230000002159 abnormal effect Effects 0.000 claims abstract description 22
- 230000008569 process Effects 0.000 claims description 12
- 238000000605 extraction Methods 0.000 claims description 4
- 238000002485 combustion reaction Methods 0.000 claims description 3
- 238000007906 compression Methods 0.000 claims description 3
- 230000017525 heat dissipation Effects 0.000 claims description 3
- 230000006835 compression Effects 0.000 claims description 2
- 238000001914 filtration Methods 0.000 claims description 2
- 230000000630 rising effect Effects 0.000 claims description 2
- 238000012423 maintenance Methods 0.000 abstract description 6
- 230000005856 abnormality Effects 0.000 description 8
- 230000000694 effects Effects 0.000 description 4
- 230000007246 mechanism Effects 0.000 description 4
- 238000012545 processing Methods 0.000 description 4
- 238000012360 testing method Methods 0.000 description 3
- 230000008859 change Effects 0.000 description 2
- 238000009499 grossing Methods 0.000 description 2
- 238000007689 inspection Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000010485 coping Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000004880 explosion Methods 0.000 description 1
- 230000036541 health Effects 0.000 description 1
- 230000008092 positive effect Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F18/00—Pattern recognition
- G06F18/20—Analysing
- G06F18/24—Classification techniques
-
- 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
- F02B77/082—Safety, indicating, or supervising devices relating to valves
-
- 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
- F02B77/083—Safety, indicating, or supervising devices relating to maintenance, e.g. diagnostic device
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M15/00—Testing of engines
- G01M15/04—Testing internal-combustion engines
- G01M15/05—Testing internal-combustion engines by combined monitoring of two or more different engine parameters
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F18/00—Pattern recognition
- G06F18/20—Analysing
- G06F18/21—Design or setup of recognition systems or techniques; Extraction of features in feature space; Blind source separation
- G06F18/213—Feature extraction, e.g. by transforming the feature space; Summarisation; Mappings, e.g. subspace methods
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F2218/00—Aspects of pattern recognition specially adapted for signal processing
- G06F2218/08—Feature extraction
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F2218/00—Aspects of pattern recognition specially adapted for signal processing
- G06F2218/12—Classification; Matching
Landscapes
- Engineering & Computer Science (AREA)
- Data Mining & Analysis (AREA)
- Theoretical Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Combustion & Propulsion (AREA)
- Chemical & Material Sciences (AREA)
- Computer Vision & Pattern Recognition (AREA)
- General Physics & Mathematics (AREA)
- Bioinformatics & Cheminformatics (AREA)
- Evolutionary Computation (AREA)
- Evolutionary Biology (AREA)
- Bioinformatics & Computational Biology (AREA)
- Artificial Intelligence (AREA)
- Life Sciences & Earth Sciences (AREA)
- Mechanical Engineering (AREA)
- Combined Controls Of Internal Combustion Engines (AREA)
Abstract
The invention relates to the technical field of engine fault diagnosis, and particularly discloses an on-line diagnosis method for engine air intake and exhaust faults, which comprises the following steps: (1) The key information of the engine is collected and compared with the calibration result; (2) Changing the rotation speed of the engine, collecting key information again, and comparing the key information with a calibration result; (3) Changing the engine speed again, collecting key information, and comparing the key information with the current working condition calibration result; (4) analyzing results; (5) Extracting the opening time of an exhaust valve and the closing time of an intake valve; and (6) distinguishing air inlet and outlet faults. By utilizing different influences of faults on engine performance under different working conditions, common faults such as abnormal valve clearance, abnormal valve timing, air leakage of a valve and the like are classified, the faults are primarily identified under the condition of not disassembling the engine, and a foundation is provided for future online engine maintenance.
Description
Technical Field
The invention relates to the technical field of engine fault diagnosis, in particular to an on-line diagnosis method for engine air intake and exhaust faults.
Background
The main function of the valve mechanism of the engine is to support the engine to complete the gas exchange process inside and outside the cylinder, thereby ensuring the normal operation of the engine. Abnormal valve clearance, abnormal valve timing and air leakage of a valve are common fault types of a valve mechanism, and have obvious influence on the performance of an engine. All three fault types may cause insufficient air quality in the cylinder to affect the efficiency of the engine, but the maintenance strategies required by different fault types are different, so specific fault reasons of the engine need to be classified when the conditions of insufficient air quality in the cylinder of the engine are faced. On the other hand, with the development of intelligent health management of the engine, the conventional fault diagnosis method for offline disassembly and inspection cannot meet the requirement of online maintenance of the engine in the future.
The current common fault classification method and countermeasures are introduced in the common fault analysis of the valve mechanism of the diesel engine published in 2019, zhuo Kaimao. The inspection methods for coping with the faults of the valve clearance abnormality, the valve timing abnormality, the valve air leakage and the like described in the literature all need to inspect relevant parts after the engine is stopped, and cannot meet the requirements of an on-line maintenance strategy of the future engine.
The application document CN 107131060A discloses a method for determining the opening and closing time of an engine valve based on dynamic cylinder pressure, which is beneficial to the diagnosis of valve actuating mechanism faults. The method described in this patent uses the variation of the polytropic index to identify the opening timing of the exhaust valve and uses the fluctuation of the in-cylinder pressure to identify the closing timing of the exhaust valve and the closing timing of the intake valve. However, the method has two obvious problems when applied to valve train fault diagnosis. Firstly, the method is established on the premise that the gas in the cylinder basically accords with the adiabatic expansion process before the exhaust valve is not opened in the expansion stroke, namely the possibility of gas leakage fault occurrence is ignored, and the gas leakage directly influences the thermal process in the cylinder, so that the method cannot be directly used for effectively classifying the faults such as abnormal valve clearance, abnormal valve timing, gas leakage and the like; in addition, through experimental tests, the method is accurate in identifying the opening time of the exhaust valve and the closing time of the intake valve, but the identification error of the closing time of the exhaust valve is large, and the opening time of the intake valve cannot be directly identified, so that the method cannot directly judge the accuracy of the phase of the intake valve and the exhaust valve.
Disclosure of Invention
The invention aims to provide an on-line diagnosis method for engine air intake and exhaust faults, which classifies common faults such as abnormal valve clearance, abnormal valve timing, air leakage and the like by utilizing different influences of faults on engine performance under different working conditions, realizes preliminary identification of the faults under the condition of no disassembly, and provides a basis for future on-line maintenance of the engine.
In order to achieve the above purpose, the invention provides an on-line diagnosis method for air intake and exhaust faults of an engine, which comprises the following steps:
(1) Acquiring key information of the engine in the current working condition state, comparing the key information with the same working condition calibration result, and judging whether an air inlet and outlet fault exists or not;
(2) Changing the rotation speed of the engine, collecting key information again, and comparing the key information with the current working condition calibration result;
(3) Changing the engine speed again, collecting key information, and comparing the key information with the current working condition calibration result;
(4) Analysis of results: key information changes along with the change of the rotating speed;
(5) Automatically extracting the opening time of an exhaust valve and the closing time of an intake valve from a dynamic cylinder pressure signal;
(6) And (5) distinguishing air inlet and exhaust faults by combining the opening time of the exhaust valve and the closing time of the intake valve obtained in the step (5).
Preferably, the key information includes cylinder pressure, exhaust temperature, and oil supply pressure.
Preferably, the air intake and exhaust faults comprise abnormal valve timing, abnormal valve clearance and air leakage of a valve.
Preferably, in the step (5), the method for extracting the opening time of the exhaust valve is as follows:
in the closed expansion process after combustion is finished, the polytropic index mainly depends on the heat dissipation condition of a wall surface, the polytropic index shows that the exhaust valve is opened when obviously rising, after filtering treatment, the first-order conduction of the polytropic index is regarded as a characteristic point of the opening of the exhaust valve when reaching 0.05 for the first time, and the polytropic index formula is as follows:
；
where n is the polytropic exponent, P is the instantaneous cylinder pressure, V is the instantaneous cylinder internal volume, i is the data point at the different time, and i+1 is the next data point of i.
Preferably, in the step (5), the method for extracting the closing timing of the intake valve is as follows:
and (3) calculating the difference value between the output cylinder pressure and the smooth cylinder pressure to obtain the fluctuation condition of the cylinder pressure in the working process of the engine, carrying out peak value extraction and fitting treatment on the pressure fluctuation signal, and respectively extracting the upper peak value and the lower peak value of the pressure fluctuation signal in the compression stroke, wherein the upper peak value and the lower peak value of the pressure fluctuation signal are the closing moment of the intake valve.
The on-line diagnosis method for the engine air inlet and outlet faults has the advantages and positive effects that:
the method can effectively classify the fault types of the intake and exhaust valves according to the performance of the engine, can diagnose under the condition of not disassembling the engine, and can not be influenced by external noise, vibration and the like.
The technical scheme of the invention is further described in detail through the drawings and the embodiments.
Drawings
FIG. 1 is a flow chart of the method of the present invention;
FIG. 2 is a graph of the effect of valve timing anomalies on engine performance at different speeds of the present invention;
FIG. 3 is a graph of the effect of valve lash anomalies on engine performance at different speeds of the present invention;
FIG. 4 is a graph showing the effect of cylinder blow-by on engine performance at different speeds in accordance with the present invention;
FIG. 5 is a graph showing the results of the first-order derivative processing and the polytropic index in the process of identifying the feature point of the opening time of the exhaust valve according to the present invention, wherein A is the result of the polytropic index processing and B is the result of the first-order derivative processing;
fig. 6 is a graph of the result of the processing of the pressure fluctuation in the intake valve closing timing characteristic point recognition process of the present invention, wherein a is a cylinder pressure fluctuation graph and B is an intake valve closing timing characteristic point graph.
Detailed Description
Unless defined otherwise, technical or scientific terms used herein should be given the ordinary meaning as understood by one of ordinary skill in the art to which this invention belongs.
Examples
An on-line diagnosis method for air intake and exhaust faults of an engine comprises the following steps:
(1) The method comprises the steps of collecting key information such as cylinder pressure, exhaust temperature, oil supply pressure and the like under the current state of a certain working condition (working condition 1) of the engine, comparing the key information with the calibration result of the same working condition (working condition 1), and judging whether an air inlet and exhaust fault exists or not, wherein the air inlet and exhaust fault comprises abnormal valve timing, abnormal valve clearance and air valve leakage. If the current working condition is 1800rpm maximum load and the test result of the engine in the current state shows that the explosion pressure is lower than the calibration result, as shown in fig. 2-4, the abnormal state can be judged, but the reason of the abnormal condition cannot be directly judged.
(2) And (3) changing the rotating speed of the engine (working condition 2), collecting key information again, and comparing the key information with the calibration result of the current working condition (working condition 2). For example, data at 1300rpm for maximum load conditions may be taken as shown in fig. 2-4.
(3) And (3) changing the rotating speed of the engine again (working condition 3), collecting key information, and comparing the key information with the calibration result of the current working condition (working condition 3). For example, data at 2100rpm for maximum load conditions may be taken as shown in fig. 2-4.
(4) Analysis of results: the key information changes with the change of the rotating speed. As the rotation speed increases, the degree of air intake and exhaust faults is increased or reduced, the degree of abnormal valve timing or abnormal valve clearance faults is increased, and the degree of air leakage faults is reduced. As shown in fig. 2-4, if the type of fault is a valve blow-by, the degree of fault is reduced when the engine speed is increased from 1300rpm to 2100 rpm. If the type of failure is a valve timing anomaly or a valve lash anomaly, the degree of failure is significantly exacerbated when the engine speed is increased from 1300rpm to 2100 rpm.
(5) And automatically extracting the opening time of the exhaust valve and the closing time of the intake valve from the dynamic cylinder pressure signal. In the step (4), the leakage fault is eliminated, and in order to further distinguish the abnormal valve timing or abnormal valve clearance fault, the actual opening time of the exhaust valve and the actual closing time of the intake valve are required to be extracted.
The specific extraction method of the opening time of the exhaust valve comprises the following steps: in the closed expansion process after combustion is finished, the polytropic index mainly depends on the heat dissipation condition of the wall surface, and the exhaust valve is opened when the polytropic index obviously rises. Calculating a polytropic index in the process by using the instantaneous cylinder pressure and the cylinder internal volume, wherein the polytropic index formula is as follows:
；
where n is the polytropic exponent, P is the instantaneous cylinder pressure, V is the instantaneous cylinder volume, i is the next data point for i at different times, i+1 is shown in FIG. 5A. The smoothing is performed by a moving average method, which belongs to the prior art and is not described herein. The first derivative of the polytropic index to the crank angle is calculated by using the polytropic index smooth curve, the first derivative is smoothed, and when the first derivative of the polytropic index after the smoothing reaches 0.05 for the first time, the characteristic point of the opening time of the exhaust valve is regarded as a characteristic point, so that the opening time of the valve can be reflected more truly, as shown in a B in fig. 5.
The specific extraction method of the closing time of the air inlet valve comprises the following steps: and calculating a difference value between the instantaneous cylinder pressure and the smooth cylinder pressure to obtain a fluctuation curve of the cylinder pressure in the working process of the engine, wherein the instantaneous cylinder pressure is the output cylinder pressure of the test equipment, and the smooth cylinder pressure is obtained by carrying out smooth treatment on the instantaneous cylinder pressure. The upper and lower peaks of the pressure fluctuation curve are extracted and fitted respectively to obtain two pressure peak smooth curves, an upper peak smooth curve and a lower upper peak smooth curve, respectively, as shown in fig. 6 a. In the compression process, the maximum value of the upper peak smooth curve and the minimum value of the lower peak smooth curve are extracted, and the earlier occurrence of the two is regarded as the characteristic point of the closing time of the intake valve, as shown in fig. 6B.
(6) And (5) distinguishing air inlet and exhaust faults by combining the opening time of the exhaust valve and the closing time of the intake valve obtained in the step (5). And (5) combining the exhaust valve opening time and the intake valve closing time obtained in the step (5) to distinguish valve timing abnormality or valve clearance abnormality. The valve clearance abnormality has a large influence on the actual opening and closing timing of the valve, but has a small influence on performance, and the valve timing abnormality is opposite to it. As shown in fig. 2 and 3, the valve clearance abnormality has a small influence on performance, and if the degree of failure is large, the same effect as that of the valve timing abnormality may occur, but the actual opening and closing timings of the valve may vary greatly.
Therefore, the method for diagnosing the engine air intake and exhaust faults on line provided by the invention classifies common faults such as abnormal valve clearance, abnormal valve timing, air leakage and the like by utilizing different influences of the faults on engine performance under different working conditions, realizes preliminary identification of the faults under the condition of not disassembling the engine, and provides a basis for future engine on-line maintenance.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention and not for limiting it, and although the present invention has been described in detail with reference to the preferred embodiments, it will be understood by those skilled in the art that: the technical scheme of the invention can be modified or replaced by the same, and the modified technical scheme cannot deviate from the spirit and scope of the technical scheme of the invention.
Claims (5)
1. An on-line diagnosis method for air intake and exhaust faults of an engine is characterized by comprising the following steps:
(1) Acquiring key information of the engine in the current working condition state, comparing the key information with the same working condition calibration result, and judging whether an air inlet and outlet fault exists or not;
(2) Changing the rotation speed of the engine, collecting key information again, and comparing the key information with the current working condition calibration result;
(3) Changing the engine speed again, collecting key information, and comparing the key information with the current working condition calibration result;
(4) Analyzing results;
(5) Automatically extracting the opening time of an exhaust valve and the closing time of an intake valve from a dynamic cylinder pressure signal;
(6) And (5) distinguishing air inlet and exhaust faults by combining the opening time of the exhaust valve and the closing time of the intake valve obtained in the step (5).
2. The on-line diagnosis method for engine air intake and exhaust faults according to claim 1, characterized in that: the key information includes cylinder pressure, exhaust temperature, and oil supply pressure.
3. The on-line diagnosis method for engine air intake and exhaust faults according to claim 1, characterized in that: the air inlet and outlet faults comprise abnormal valve timing, abnormal valve clearance and air leakage of the valve.
4. The on-line diagnosis method for engine air intake and exhaust faults according to claim 1, characterized in that: in the step (5), the method for extracting the opening time of the exhaust valve is as follows:
in the closed expansion process after combustion is finished, the polytropic index mainly depends on the heat dissipation condition of a wall surface, the polytropic index shows that the exhaust valve is opened when obviously rising, after filtering treatment, the first-order conduction of the polytropic index is regarded as a characteristic point of the opening of the exhaust valve when reaching 0.05 for the first time, and the polytropic index formula is as follows:
；
where n is the polytropic exponent, P is the instantaneous cylinder pressure, V is the instantaneous cylinder internal volume, i is the data point at the different time, and i+1 is the next data point of i.
5. The on-line diagnosis method for engine air intake and exhaust faults according to claim 1, characterized in that: in the step (5), the method for extracting the closing time of the intake valve is as follows:
and (3) calculating the difference value between the output cylinder pressure and the smooth cylinder pressure to obtain the fluctuation condition of the cylinder pressure in the working process of the engine, carrying out peak value extraction and fitting treatment on the pressure fluctuation signal, and respectively extracting the upper peak value and the lower peak value of the pressure fluctuation signal in the compression stroke, wherein the upper peak value and the lower peak value of the pressure fluctuation signal are the closing moment of the intake valve.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311008854.XA CN116756621A (en) | 2023-08-11 | 2023-08-11 | On-line diagnosis method for air inlet and outlet faults of engine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311008854.XA CN116756621A (en) | 2023-08-11 | 2023-08-11 | On-line diagnosis method for air inlet and outlet faults of engine |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116756621A true CN116756621A (en) | 2023-09-15 |
Family
ID=87948079
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311008854.XA Pending CN116756621A (en) | 2023-08-11 | 2023-08-11 | On-line diagnosis method for air inlet and outlet faults of engine |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116756621A (en) |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008019818A (en) * | 2006-07-14 | 2008-01-31 | Denso Corp | Control device of internal combustion engine |
| CN106338400A (en) * | 2016-08-26 | 2017-01-18 | 哈尔滨东安汽车发动机制造有限公司 | Engine valve fly-off test method |
| CN107131060A (en) * | 2017-05-09 | 2017-09-05 | 北京理工大学 | It is a kind of that the method for determining the engine valve open and close moment is pressed based on dynamic cylinder |
| CN109083756A (en) * | 2018-09-28 | 2018-12-25 | 潍柴动力股份有限公司 | A kind of engine charge fault detection method and device |
| CN114943117A (en) * | 2022-05-23 | 2022-08-26 | 北京理工大学 | Indicated thermal efficiency calculation digital correction method based on actual measurement cylinder pressure curve |
| CN115247606A (en) * | 2022-04-29 | 2022-10-28 | 长城汽车股份有限公司 | Engine fault processing method, control equipment and storage medium |
| CN116428070A (en) * | 2023-03-28 | 2023-07-14 | 长城汽车股份有限公司 | Variable valve timing mechanism fault abnormality processing method, system and vehicle |
-
2023
- 2023-08-11 CN CN202311008854.XA patent/CN116756621A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008019818A (en) * | 2006-07-14 | 2008-01-31 | Denso Corp | Control device of internal combustion engine |
| CN106338400A (en) * | 2016-08-26 | 2017-01-18 | 哈尔滨东安汽车发动机制造有限公司 | Engine valve fly-off test method |
| CN107131060A (en) * | 2017-05-09 | 2017-09-05 | 北京理工大学 | It is a kind of that the method for determining the engine valve open and close moment is pressed based on dynamic cylinder |
| CN109083756A (en) * | 2018-09-28 | 2018-12-25 | 潍柴动力股份有限公司 | A kind of engine charge fault detection method and device |
| CN115247606A (en) * | 2022-04-29 | 2022-10-28 | 长城汽车股份有限公司 | Engine fault processing method, control equipment and storage medium |
| CN114943117A (en) * | 2022-05-23 | 2022-08-26 | 北京理工大学 | Indicated thermal efficiency calculation digital correction method based on actual measurement cylinder pressure curve |
| CN116428070A (en) * | 2023-03-28 | 2023-07-14 | 长城汽车股份有限公司 | Variable valve timing mechanism fault abnormality processing method, system and vehicle |
Non-Patent Citations (2)
| Title |
|---|
| 薄亚卿 等: "基于缸压分析的发动机实际气门开闭相位诊断研究", 设计与智能制造2022学术年会, pages 1 - 8 * |
| 钟云刚;: "利用气缸压力波形诊断汽车故障", 汽车电器, no. 07, pages 64 - 65 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110954312B (en) | Reciprocating mechanical fault diagnosis method based on keyless phase whole-cycle signal | |
| US9399958B2 (en) | Specifying method of EGR rate in internal combustion engine and control apparatus of internal combustion engine | |
| CN102713226B (en) | Abnormality detection device for exhaust gas recirculation device | |
| CN110261127B (en) | On-line detection method for carbon deposit jamming of variable cross-section turbocharger of engine | |
| CN109026277A (en) | Internal combustion engine crankcase ventilation system leakage monitoring structure and its monitoring method | |
| CN116481821A (en) | Engine fault early warning method and system based on big data analysis management | |
| CN114738132B (en) | Supercharger rotation speed sensor fault diagnosis method and system based on real ship data | |
| CN111868356B (en) | Method for checking variable valve lift control of an internal combustion engine | |
| CN116756621A (en) | On-line diagnosis method for air inlet and outlet faults of engine | |
| JPH0925851A (en) | Diagnostic device for exhaust reflux device of internal combustion engine | |
| US8428809B2 (en) | Multi-step valve lift failure mode detection | |
| KR102457752B1 (en) | Method of real time fault detection and diagnosis for onboard engine room and system for forperming the same | |
| US11401881B2 (en) | Fourier diagnosis of a charge cycle behavior of an internal combustion engine | |
| CN108536961B (en) | Marine diesel engine air valve quantitative detection device | |
| CN112668419A (en) | Engine emission prediction method based on vibration signal | |
| CN116577104A (en) | Engine fault detection method and equipment | |
| CN102341582B (en) | Apparatus for determining abnormal combustion in internal combustion engine | |
| CN114662314A (en) | Working condition switching-oriented marine diesel engine thermal parameter estimation method | |
| CN114611558A (en) | Method for online detection of surge of centrifugal compressor of turbocharger | |
| CN112796879A (en) | On-line testing method and device for air valve clearance of marine diesel engine | |
| Corsini et al. | Internal Combustion Engine sensor network analysis using graph modeling | |
| CN117830193A (en) | Reciprocating compressor multi-fault diagnosis method based on characteristic extraction of indicator diagram | |
| Wei et al. | Using fuzzy method to evaluate safety condition of big diesel engine | |
| Yang et al. | Research on Fault Diagnosis Method of Diesel Engine Thermal Power Conversion Process | |
| Chenchao | FAULT DIAGNOSIS OF MARINE DIESEL ENGINE BASED ON MIXED SIMILARITY ALGORITHM |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |