CN107747924A - Working process of diesel engine cylinder oil film thickness ultrasonic measurement simulation test device - Google Patents
Working process of diesel engine cylinder oil film thickness ultrasonic measurement simulation test device Download PDFInfo
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- CN107747924A CN107747924A CN201711134020.8A CN201711134020A CN107747924A CN 107747924 A CN107747924 A CN 107747924A CN 201711134020 A CN201711134020 A CN 201711134020A CN 107747924 A CN107747924 A CN 107747924A
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- oil film
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- sensor
- film thickness
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B17/00—Measuring arrangements characterised by the use of infrasonic, sonic or ultrasonic vibrations
- G01B17/02—Measuring arrangements characterised by the use of infrasonic, sonic or ultrasonic vibrations for measuring thickness
- G01B17/025—Measuring arrangements characterised by the use of infrasonic, sonic or ultrasonic vibrations for measuring thickness for measuring thickness of coating
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- General Physics & Mathematics (AREA)
- Length Measuring Devices Characterised By Use Of Acoustic Means (AREA)
- Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)
Abstract
It is an object of the invention to provide working process of diesel engine cylinder oil film thickness ultrasonic measurement simulation test device, motor connects bent axle by shaft coupling, TDCS TDC Sensor and position sensor are installed on bent axle, the connection display of injection system one end and controller, the other end connects the combustion chamber above piston by check valve, the heater of connection display and controller is set in combustion chamber, cylinder jacket outer wall sets transducer, transducer connects multiplexer switch, multiplexer switch is sequentially connected signal amplifier, pulse generation/receiver, data acquisition unit, display and controller, mounting temperature sensor and pressure sensor in cylinder jacket above combustion chamber, temperature sensor, pressure sensor, TDCS TDC Sensor, position sensor is all connected with data acquisition unit.The present invention can both measure the oil film situation of change in cylinder piston motion process, can simulate the motion process of diesel engine again, realize working process of diesel engine cylinder oil film thickness ultrasonic measurement simulated test.
Description
Technical field
The present invention relates to a kind of simulation test device, specifically cylinder of diesel engine oil film thickness simulated test fills
Put.
Background technology
Boat diesel engine cylinder operation pressure height, temperature height, lubricating difficulties, condition of work are severe, therefore cylinder lubrication is
Influence one of principal element of diesel engine work.Statistics shows that the failure caused by lubricating reason accounts for total failare
40%.In diesel engine work, because cylinder wall and piston interannular pressure are larger, the linear velocity between big load impact and surface,
Oil film is caused to become very thin, it is easily damaged so that contact surface is in dry condition, the temperature significantly rise and abrasion of contact surface
Obvious aggravation, ultimately results in engine cisco unity malfunction, engine will be caused to damage under serious conditions.And when oil film is blocked up
When, it can cause occur oil leakage phenomenon in the course of work again, bearing capacity declines, phenomena such as job insecurity.As can be seen here, properly
Cylinder oil film thickness be engine can normal work a key factor, the lubrication state of visual plant is supervised
Survey, grasp lubricating utensil state just seem extremely important, and currently used for cylinder oil film thickness monitoring detection method have it is a variety of,
Respectively there is the characteristics of different.
Electrical method needs a conductive plane or an osculating element being electrically isolated completely to come install sensor, optics side
Method major defect is made of that one of two contacts must use transparent material, and in measurement, this entity for just needing to contact with oil film is
Transparent or physically leave the window for transmitting light beam, the actual condition of this and machine components has bigger difference.
Ultrasonic detecting technology have applicability is wide, flaw detection sensitivity is high, penetration capacity is strong, Noninvasive, detection depth are big,
The advantages that easy to use and security is good, it is one of current widely used non-destructive testing technology.Domestic and foreign scholars propose ultrasound
The method of wave measurement lubricant thickness, and carried out numerous studies.
Tattersall H G. in 1973 carry out bonding test by ultrasonic pulse method, if the medium II in embedding medium I
It is thin layer compared with I, then medium II can be replaced by light spring.The main research medium such as Jong-Ryul Park in 1985 is thick
Degree, ultrasonic frequency and medium acoustic impedance measure ultrasound method the influence of liquid film thickness.2004
R.S.Dwyer-Joyce and B.W.Drinkwater etc. measures to oil film thickness respectively.Analyze different theories measuring method
Applicable oil film thickness scope, and devise the measurement apparatus for static and dynamic oil film layer.
Coming years, Bruce W.Drinkwater research teams have done further research to ultrasonic method of measuring. 2005
Year, Jie Zhang, Bruce W.Drinkwater etc. is directed to the shortcomings that ultrasonic technology lacks calibration procedure, inquires into lubricating oil
The calibration of film thickness ultrasonic measurement technology, promotes the development of ultrasonic measurement technology.2008, they were to sonac line
Property array studied, and vertical incidence is expanded to the oblique incidence ultrasonic measurement of any angle, is 2~9 μm to thickness
Oil film has carried out experiment and measurement accuracy is higher.Hunter A J and Drinkwater B W have studied automatic in Non-Destructive Testing
Focus issues, and the geometry of complexity is assessed using supersonic array.
2011, D.Gasni, M.K.Wan Ibrahim, R.S.Dwyer-Joyce have studied coarse table in spring model
Reflectance factor and stiffness relation when face contacts, it is not direct relevant with area that is actually contacting to draw reflectance factor, but is depended on
In number, shape and the distribution of surface contact micro-bulge.The same year, Dwyer-Joyce.R.S have studied elastohydrodynamic lubrication
Ultrasound film thickness measuring mechanism when middle boundary lubrication or mixed lubrication, and it is verified by experiment.
Domestic scholars have also carried out research and development to ultrasonic measurement method.Zhang Rui in 2001 et al. is in reflective transitive function
On the basis of, propose that frequency domain levies method and inverse algorithmses and the parameters such as the velocity of sound of elastic single-layer medium, thickness and density are determined surely
Sign.2007, Lu Liming research and utilization impulse ejections method measured the oil film thickness of liquid sliding bearing, test the result of acquisition with
Notional result is consistent.2009, Jiao Jingpin, Zhang Qiang et al. have studied propagation and influence reflection system of the ultrasonic wave in three layers of medium
Several various factors.Experimental analysis is carried out to the method, media of both sides material is obtained and changes to the no shadow of liquid layer thickness measurement
The loud and measurement result conclusion relevant with the material character of measured layer.Tang Wei in 2010 is female to have delivered entitled " utilization reflection system
The article of the research of number measurement oil film thickness ".Shen flood seedling analyzes ultrasonic frequency, ultrasonic wave incident angle and lubrication within 2013
Affecting laws of the agent thickness to reflectance factor.
The content of the invention
It is an object of the invention to provide the working process of diesel engine that system test analysis can be carried out to oil film changing rule
Cylinder oil film thickness ultrasonic measurement simulation test device.
The object of the present invention is achieved like this：
Working process of diesel engine cylinder oil film thickness ultrasonic measurement simulation test device of the present invention, it is characterized in that：Including
Cylinder piston linkage, display and controller, data acquisition unit, pulse generation/receiver, signal amplifier, multiplexing
Switch, injection system, cylinder piston linkage include cylinder jacket, piston, connecting rod, bent axle, motor, and motor is connected by shaft coupling
Bent axle is connect, TDCS TDC Sensor and position sensor, the connection display of injection system one end and controller, the other end are installed on bent axle
Combustion chamber above piston is connected by check valve, the heater of connection display and controller is set in combustion chamber, outside cylinder jacket
Wall set transducer, transducer connection multiplexer switch, multiplexer switch be sequentially connected signal amplifier, pulse generation/
Receiver, data acquisition unit, display and controller, mounting temperature sensor and pressure sensing in the cylinder jacket above combustion chamber
Device, temperature sensor, pressure sensor, TDCS TDC Sensor, position sensor are all connected with data acquisition unit.
The present invention can also include：
1st, the position of piston is calculated using position sensor and top dead center position sensor, is sent out by display and controller
Go out instruction, merge corresponding multiplexer switch, so that its corresponding transducer work；Meanwhile by showing and controlling
Device sends excitation pulse generation/receiver instruction again, and pulse generation/receiver sends pulse signal, opened by multiplexing
Pass excites transducer, and transducer produces ultrasonic wave, and cylinder oil film is injected after focusing, and ultrasonic reflections signal is received by transducer,
Received by multiplexer switch, signal amplifier by pulse generation/receiver, by signal acquisition to display and control
Device；The reflectance ultrasound ripple signal after filtering and FFT, becomes frequency-region signal, for the amplitude before and after ultrasonic reflections, meter
Reflectance factor is calculated, then using the equivalent spring model or resonance model, calculates oil film thickness.
Advantage of the invention is that：The present invention can both utilize the equivalent spring model or resonance model, measure cylinder piston
Oil film situation of change in motion process, the motion process of diesel engine can be simulated again, realizes working process of diesel engine cylinder oil
Film thickness ultrasonic measurement simulated test.
Brief description of the drawings
Fig. 1 is the structural representation of the present invention.
Embodiment
Illustrate below in conjunction with the accompanying drawings and the present invention is described in more detail：
With reference to Fig. 1, measuring system of the present invention includes display and controller 1, data acquisition unit 2, pulse generation/receiver
3rd, signal amplifier 4, multiplexer switch 5, transducer, temperature sensor 18, pressure sensor, position sensor 8, motor
11st, cylinder jacket 14, bent axle 9, overflow valve, check valve, choke valve, injection system 6, heater 17, transducer, piston 13, piston
The parts such as ring 15, water jacket 16, connecting rod 12, bent axle 9, shaft coupling 10.
Piston ring 15, piston 13, cylinder jacket 14, connecting rod 12, bent axle 9, water jacket 16 form the basic cylinder of a diesel engine and lived
Plug structure.Shaft coupling 10 connects motor 11 and bent axle 9, and under display and the instruction of controller 1, motor 11 is with dynamic crankshaft
9 rotate, and drag piston and pump, and under different control instructions, the rotating speed of motor 11 is different, then piston 13 is past
Multiple movement velocity is different.
When piston 13 moves downward, gas enters in cylinder from check valve, while oil syringe is in display and controller 1
Under instruction, the lubricating oil spraying into cylinder, prevent from that dry friction occurs between cylinder and piston.When the piston is moving up, gas quilt
Compression, simulate the cylinder compression process of diesel engine.The aperture of choke valve can be adjusted, simulates different gas pressures；Adjustment is overflow
The pressure size of valve is flowed, prevents pressure is excessive from accident occurs.
Under display and the instruction of controller 1, heater 17 is operated, and utilizes the closed-loop control of temperature sensor 18
Temperature in cylinder.
Multiplexer switch 5 realize multiple transducers excite and data acquisition.
Temperature sensor 18 and pressure sensor are used for the plunger auxiliary air gap of corrected Calculation.
Position sensor 8 and TDCS TDC Sensor 7 are used for the position for calculating piston 13, to excite the transducing of relevant position
Device, and the work of control oil syringe.
Display and controller 1 are used for plunger pair gap and calculate and correct, and control multiplexer switch 5, excite relevant position
The function such as transducer.
The present invention can include multiple ultrasonic transducers, and these transducers realize a survey by multiplexer switch 5
Amount passage can complete the clearance measurement to the multiple height and positions of plunger pair.
Display and controller 1 control heater 17 to work, and for heating the gas in cylinder, simulate warm in different cylinders
Degree.
Breather check valve ensures in piston intake stroke, sucks air, in compression travel, prevents gas in cylinder
Body.
Overflow valve is used for protective effect, prevents that the air pressure in cylinder is excessive in compression travel for piston；
Choke valve is used to adjust piston in compression travel, the air pressure in cylinder；
Including an angle position sensor 8 of bent axle 9 and TDCS TDC Sensor 7, for the motion bit of plunger to be calculated
Put, realize to respective transducer excitation ultrasound ripple, and carry out DATA REASONING.
The present invention in actual applications, real time temperature and pressure in cylinder is obtained using temperature and pressure sensor.When
When needing to adopt the oil film thickness in somewhere between cylinder and piston, the position sensor 8 of bent axle 9 and top dead center position sensor 8 are utilized
The position of piston is calculated, when the opening position has corresponding transducer, display and controller 1 send instruction, make corresponding more
Road multiplex switch 5 merges, and the transducer can work；Meanwhile display and controller 1 send excitation pulse generation/reception again
Device 3 instructs, and pulse generation/receiver 3 sends pulse signal, excites transducer by multiplexer switch 5, transducer produces
Ultrasonic wave, injects cylinder oil film after focusing, ultrasonic reflections signal is received by transducer, put by multiplexer switch 5, signal
Big device 4 is received by pulse generation/receiver 3, by signal acquisition to display and controller 1.The reflectance ultrasound ripple signal passes through
Filtering and FFT are crossed, becomes frequency-region signal, for the amplitude before and after ultrasonic reflections, calculates reflectance factor, then utilize
The equivalent spring model or resonance model, calculate oil film thickness.
Multiple transducers are arranged in difference cylinder height and position and circumferential position by design, pistons work mistake can be obtained
In journey between cylinder and piston oil film change profile.
When the thickness of oil film is much smaller than the wavelength of ultrasonic wave, oil film thickness is calculated using the equivalent spring model；Work as oil film
Thickness it is close with the wavelength of ultrasonic wave when, using resonance model calculate oil film thickness.
Temperature and pressure has an impact to the density and the velocity of sound of fuel oil, under different temperature and pressures, the density harmony of fuel oil
It is fast different, therefore, the density and the velocity of sound of fuel oil are modified using temperature and pressure sensor, can be calculated relatively accurate
Oil film thickness numerical value.
Working process of diesel engine cylinder oil film thickness ultrasonic measurement simulation test device, including display and controller 1, number
According to collector 2, pulse generation/receiver 3, signal amplifier 4, multiplexer switch 5, transducer, temperature sensor 18, pressure
Sensor, position sensor 8, motor 11, cylinder jacket 14, piston, bent axle 9, overflow valve, check valve, choke valve, injection system 6,
The parts such as heater 17, transducer, piston, piston ring 15, cylinder jacket 14, water jacket 16, connecting rod 12, bent axle 9, shaft coupling 10, it is real
The motion of cylinder of diesel engine piston is now simulated, and utilizes the oil film during ultrasonic measurement pistons work between cylinder and piston
Thickness function.
Ultrasonic transducer is arranged in cylinder jacket 14, transducer end face and cylinder jacket 14 and the spacing of piston interface
From 5-12mm.
Display and controller 1 control heater 17 to work, and for heating the gas in cylinder, simulate warm in different cylinders
Degree.
There is stomata to connect breather check valve on cylinder end face, ensure in piston intake stroke, suck air, compressing
During stroke, cylinder interior gas is prevented.
There is stomata to connect overflow valve on cylinder end face, for protective effect, piston is prevented in compression travel, in cylinder
Air pressure is excessive；
There is stomata to connect choke valve, for adjusting piston in compression travel, the air pressure in cylinder on cylinder end face.
Controlled by multiplexer switch 5, realize the multiple ultrasonic transducer data of a Measurement channel acquisition time, it is complete
The oil film thickness measurement of the multiple height and positions of paired cylinder.
One angle position sensor 8 of bent axle 9 and top dead center position sensor 8 are installed on bent axle 9, for calculating
To the movement position of piston, respective transducer excitation ultrasound ripple is controlled, and the data of back wave are measured.
Claims (2)
1. working process of diesel engine cylinder oil film thickness ultrasonic measurement simulation test device, it is characterized in that：Including cylinder piston
Linkage, display and controller, data acquisition unit, pulse generation/receiver, signal amplifier, multiplexer switch, oiling
System, cylinder piston linkage include cylinder jacket, piston, connecting rod, bent axle, motor, and motor connects bent axle by shaft coupling, bent
TDCS TDC Sensor and position sensor are installed, the connection display of injection system one end and controller, the other end pass through unidirectional on axle
Valve connects the combustion chamber above piston, and the heater of connection display and controller is set in combustion chamber, and cylinder jacket outer wall sets and changed
Energy device, transducer connection multiplexer switch, multiplexer switch are sequentially connected signal amplifier, pulse generation/receiver, number
According to collector, display and controller, mounting temperature sensor and pressure sensor in the cylinder jacket above combustion chamber, TEMP
Device, pressure sensor, TDCS TDC Sensor, position sensor are all connected with data acquisition unit.
2. working process of diesel engine cylinder oil film thickness ultrasonic measurement simulation test device according to claim 1, its
It is characterized in：The position of piston is calculated using position sensor and top dead center position sensor, is sent by display and controller
Instruction, merge corresponding multiplexer switch, so that its corresponding transducer work；Meanwhile pass through display and controller
Excitation pulse generation/receiver instruction is sent again, and pulse generation/receiver sends pulse signal, by multiplexer switch
Transducer is excited, transducer produces ultrasonic wave, and cylinder oil film is injected after focusing, and ultrasonic reflections signal is received by transducer, passes through
Cross multiplexer switch, signal amplifier is received by pulse generation/receiver, by signal acquisition to showing and controller；
The reflectance ultrasound ripple signal after filtering and FFT, becomes frequency-region signal, for the amplitude before and after ultrasonic reflections, calculates
Go out reflectance factor, then using the equivalent spring model or resonance model, calculate oil film thickness.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711134020.8A CN107747924A (en) | 2017-11-16 | 2017-11-16 | Working process of diesel engine cylinder oil film thickness ultrasonic measurement simulation test device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711134020.8A CN107747924A (en) | 2017-11-16 | 2017-11-16 | Working process of diesel engine cylinder oil film thickness ultrasonic measurement simulation test device |
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| CN107747924A true CN107747924A (en) | 2018-03-02 |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109540718A (en) * | 2018-12-03 | 2019-03-29 | 潍柴动力股份有限公司 | A kind of experimental rig of dry seed |
| CN109737901A (en) * | 2019-03-12 | 2019-05-10 | 西安交通大学 | Solve the insufficient method of cylinder roller bearing ultrasound film thickness measuring spatial resolution |
| CN113958382A (en) * | 2021-10-20 | 2022-01-21 | 中船动力研究院有限公司 | Low-speed diesel engine electronic cylinder oiling control system |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109540718A (en) * | 2018-12-03 | 2019-03-29 | 潍柴动力股份有限公司 | A kind of experimental rig of dry seed |
| CN109737901A (en) * | 2019-03-12 | 2019-05-10 | 西安交通大学 | Solve the insufficient method of cylinder roller bearing ultrasound film thickness measuring spatial resolution |
| CN109737901B (en) * | 2019-03-12 | 2020-07-24 | 西安交通大学 | Method for solving insufficient spatial resolution of ultrasonic film thickness measurement of cylindrical roller bearing |
| CN113958382A (en) * | 2021-10-20 | 2022-01-21 | 中船动力研究院有限公司 | Low-speed diesel engine electronic cylinder oiling control system |
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Application publication date: 20180302 |