Claims:1. A method (70) for monitoring contaminant dilution in lubricating oil (14) used in a reciprocating engine (12), the method comprising:
generating (80) a plurality of calibration relationship profiles for a change with respect to time of one or more oil integrity measurands for the lubricating oil (14);
generating (90) two or more correction parameters based on the plurality of calibration relationship profiles;
receiving (100) a plurality of sensor measurements for the one or more oil integrity measurands for the lubricating oil;
generating(110) a plurality of measurement profiles based on the plurality of sensor measurements;
applying (120) the two or more correction parameters on the plurality of measurement profiles to generate (130) a corrected relationship profile for a change with respect to time of one or more fuel integrity measurands for the lubricating oil in the reciprocating engine;
determining (140) an amount of contaminant dilution for one or more contaminants in the lubricating oil based on the corrected relationship profile; and
generating (150) a control action for an optimal operation of the reciprocating engine based on the amount of contaminant dilution.
2. The method (70) of claim 1 wherein the one or more contaminants comprise at least one of fuel or water or combination of fuel and water or soot.
3. The method (70) of claim 1 wherein the one or more oil integrity measurands comprise at least one of kinematic viscosity and dielectric constant.
4. The method (70) of claim 1 wherein generating calibration relationship profile is in a laboratory environment.
5. The method (70) of claim 1 wherein the plurality of sensor measurements for the one or more oil integrity measurands are generated for the reciprocating engine (12) under operation.
6. A lubricating oil system (10) for a reciprocating engine (12), the lubricating oil system (10) comprising:
a lubricating oil circuit (28) configured for circulating lubricating oil (14) for lubricating a plurality of components of the reciprocating engine;
a plurality of sensors (30) disposed along the lubricating oil circuit (28) for measuring one or more oil integrity measurands of the lubricating oil (14);
a contaminant dilution monitoring module (32) configured for determining an amount of contaminant dilution for one or more contaminants in the lubricating oil (14); and
a controller(34) configured for generating one or more control actions based on the contaminant dilution for optimal operation of the reciprocating engine (12).
7. The lubricating oil system (10) of claim 6 wherein the contaminant dilution monitoring module (32) comprises:
a calibration module (40) comprising a plurality of calibration relationship profiles for a change of one or more oil integrity measurands with respect to time for the reciprocating engine, and configured for generating two or more correction parameters based on the plurality of calibration relationship profiles;
an input module (46) configured for receiving a plurality of sensor measurements for the one or more oil integrity measurands for the reciprocating engine;
an analysis module (50) configured for generating a plurality of measurement profiles based on the plurality of sensor measurements, applying the two or more correction parameters on the plurality of measurement profiles to generate a corrected relationship profile for change of one or more fuel integrity measurands with respect to time, and for determining an amount of contaminant dilution for one or more contaminants based on the corrected relationship profile; and
a communication module (60) configured for communicating the amount of contaminant dilution to the controller.
8. The lubricating oil system (10) of claim 7 wherein the one or more contaminants comprise at least one of fuel or water or combination of fuel and water or soot.
9. The lubricating oil system (10) of claim 7 wherein the one or more oil integrity measurands comprise at least one of kinematic viscosity and dielectric constant.
10. The lubricating oil system (10) of claim 7 wherein the one or more control actions comprise generation of an alarm as an indication for oil change for the reciprocating engine (12) based on the amount of contaminant dilution.
, Description:BACKGROUND
[0001] This disclosure relates generally to a lubricating oil system for a reciprocating engine and more particularly to lubricating oil contamination due to leakage of fuel and water into the lubricating oil in the reciprocating engine.
[0002] The reciprocating engine is used for example, in different vehicles such as locomotives, automobiles etc., and the lubricating oil system is used for providing a supply of lubricating oil to the various moving parts of the reciprocating engine. The main function of the lubricating oil system is to enable the formation of a film of oil between the moving parts, which reduces friction and wear. The lubricating oil is also used as a cleaner and in some reciprocating engines as a coolant.
[0003] Due to the severe operating load, speed, temperature and the introduction of contaminants into the lubrication oil system, there are chances that the operating environment gradually lowers the lubrication oil properties and hence it becomes harmful for the engine operation. Therefore, analysis of lubricating oil is done periodically, as a part of engine maintenance, to identify and analyze the possible sources of contamination and monitor them from time to time.
[0004] Some of the common lubricating oil contamination reasons include leakage of fuel in the lubricating oil system, because of which there is a reduction in flashpoint, viscosity, and load carrying capacity of the lubricating oil. Another reason is leakage of water in the lubricating oil due to which there are chances of formation of emulsion and reduction of load carrying capacity of the lubricating oil.
[0005] Analysis of lubricating oil is typically done by sending a sample of the lubricating oil to a laboratory for analysis. The oil may be subjected to tests such as viscosity, fuel oil dilution, water, solid impurities, etc. Such analysis may sometime take some days or weeks for completion, and the lubricating oil may deteriorate further in this time period, exposing greater risk for engine operation. In other cases, the analysis may be dependent only on sensor inputs from on-board sensors (i.e. sensors deployed on the reciprocating engine) and the quality of measurements by the sensor impact the analysis results.
BRIEF DESCRIPTION
[0006] In one aspect, a method for monitoring contaminant dilution in lubricating oil used in a reciprocating engine is described herein. The method includes steps for generating calibration relationship profiles for a change with respect to time of one or more oil integrity measurands for the lubricating oil; and generating two or more correction parameters based on the calibration relationship profiles. The method then includes receiving sensor measurements for the one or more oil integrity measurands for the lubricating oil; and generating measurement profiles based on the sensor measurements. The method further includes applying the two or more correction parameters on the measurement profiles to generate a corrected relationship profile for a change with respect to time of one or more fuel integrity measurands for the lubricating oil, in the reciprocating engine; and determining an amount of contaminant dilution for one or more contaminants in the lubricating oil based on the corrected relationship profile. The method then includes generating a control action for an optimal operation of the reciprocating engine based on the amount of contaminant dilution.
[0007] A lubricating oil system for a reciprocating engine is described herein. The system includes a lubricating oil circuit for circulating lubricating oil for lubricating different components of the reciprocating engine. The lubricating oil system further includes sensors disposed along the lubricating oil circuit for measuring one or more oil integrity measurands of the lubricating oil. The system also includes a contaminant dilution monitoring module for determining an amount of contaminant dilution for one or more contaminants in the lubricating oil; and a controller for generating one or more control actions based on the contaminant dilution for optimal operation of the reciprocating engine.
DRAWINGS
[0008] These and other features, aspects, and advantages of the present disclosure will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:
[0009] FIG. 1 is a diagrammatic representation of a lubricating oil system for a reciprocating engine;
[0010] FIG. 2 is a diagrammatic representation of a contaminant dilution monitoring module used in the lubricating oil system of FIG.1;
[0011] FIG. 3 is a graphical representation of calibration relationship profiles used in the contaminant dilution monitoring module of FIG. 2;
[0012] FIG. 4A, and FIG. 4B, are graphical representations showing measurement data and measurement profiles obtained from sensor data and sensor measurements;
[0013] FIG 5A is a graphical representation of application of calibration profiles on the measurement profiles, and FIG. 5B is a graphical representation of a corrected relationship profile for determining percent dilution in the lubricating oil, in accordance with the embodiments of FIG. 1 and FIG.2; and
[0014] FIG. 6 is a flowchart representation of a method for monitoring contaminant dilution in the lubricating oil for the reciprocating engine, in accordance with an aspect of the disclosure.
DETAILED DESCRIPTION
[0015] The foregoing description is directed to particular embodiments described herein is for the purpose of illustration and explanation. It will be apparent, however, to one skilled in the art that many modifications and changes to the embodiments set forth above are possible without departing from the scope and the spirit of the disclosure. It is intended that the following claims be interpreted to embrace all such modifications and changes.
[0016] As explained herein above, an accurate and timely analysis of the level of contaminants in the lubricating oil is one of the valuable preventive maintenance tools for the reciprocating engine(s) (also referred as “engine(s)” herein), that enables optimal control actions for engine operation, to avoid a major repair. The contaminants described herein include fuel, water, or combination of fuel and water, or soot as non-limiting exemplary contaminants, however the aspects described herein may be applied to other contaminants as well.
[0017] It would be appreciated by those skilled in the art that the lubricating oil analysis can be advantageously used for increasing the engine's life, decreasing failure rate of engines, and reduce repair costs. The aspects described herein relate to using sensor measurements from the sensors deployed in the lubricating oil system (for example on-board sensors), and correcting these sensor measurements, based on data parameterization approach, to derive percent contaminant dilution in the lubricating oil.
[0018] FIG. 1 is a diagrammatic representation of a lubricating oil system 10 for a reciprocating engine 12. Typically, the lubricating oil 14 for the engine 12 is stored in the bottom of a crankcase, known as “sump” 16, or in a drain tank located beneath the engine 12. The lubricating oil 14 is drawn from this tank through a strainer 18, one of a pair of pumps 20, into one of a pair of fine filters 22. The lubricating oil 14 is then passed through a cooler 24 before entering the engine 12 and being distributed to the various branch pipes to reach the different components of the engine 12, referred generally by distribution manifold 26. Pumps 20 and fine filters 22 are arranged in duplicate with one as standby. The fine filters 22 are arranged so that one can be cleaned while the other is operating. After use in the engine 12, the lubricating oil 14 drains back to the sump 16 or drain tank for re-use. The sump 16, strainer 18, pair of pumps 20, pair of fine filters 22, cooler 24, distribution manifold 26 form a lubricating oil circuit 28, for the flow of lubricating oil 14 for lubricating different components of the reciprocating engine. The different components may typically include different bearings, cylinder liners etc.
[0019] The lubricating oil system 10 also includes some sensors 30 disposed along the lubricating oil circuit for measuring one or more oil integrity measurands. The sensors 30 selected are typically rugged to withstand the temperatures and pressures during the operation of the reciprocating engine.
[0020] The lubricating oil system 10 further includes a contaminant dilution monitoring module 32 for determining an amount of contaminant dilution for one or more contaminants using a parameterized approach described herein below in reference to FIG. 2 in more detail. The lubricating oil system 10 further includes a controller 34 for generating one or more control actions 36 based on the contaminant dilution for optimal operation of the reciprocating engine 12. The control actions include, for example, generation of an alarm as an indication for oil change for the reciprocating engines based on the amount of contaminant dilution.
[0021] FIG. 2 is a diagrammatic representation of the contaminant dilution monitoring module 32 mentioned herein above. The contaminant dilution monitoring module 32 includes a calibration module 40 which contains calibration relationship profiles 42 for a change of one or more oil integrity measurands with respect to time, at different known percent dilution of contaminants in the comparable lubricating oil, as is used in the reciprocating engine. The one or more oil integrity measurands include for example, kinematic viscosity (required for measuring percent fuel dilution in the lubricating oil) and dielectric constant (required for measuring percent water dilution in the lubricating oil).
[0022] It would be appreciated by those skilled in the art that these calibration relationship profiles are advantageously developed offline in a laboratory environment, using a highly sensitive sensor system to ensure accuracy of measurements and removal of errors that typically arise in measurements in a field environment (also referred as “onboard” environment or “in-use” environment, or “under operation” environment or “during operation” environment, also the word “environment” may not be used every time for retaining the flow of description).
[0023] It would also be appreciated by those skilled in the art, that the development of calibration relationship profiles 42 is a one time effort, and using these calibration relationship profiles, the sensor measurements obtained during the operation of the reciprocating engine can be corrected efficiently, without the need to obtain a separate sample of the lubricating oil at periodic intervals, that then needs to be sent to a laboratory for measurement of the contaminant level. Thus the system and method described herein ensures more accurate and timely measurements that are obtained directly from the sensor measurements, obviating the need for sending periodic samples of the lubricating oil to a laboratory.
[0024] The calibration module 40 mentioned herein above uses the calibration relationship profiles 42 for generating two or more correction parameters 44. In a specific example, the following equation is used for parameterization:
[0025] …Equation 1,
where AP represents Kinematic viscosity obtained from the calibration relationship profiles; T represents temperature; f is a relationship function between the Kinematic viscosity and temperature; m1, c1, m2, c2 are four correction parameters generated by solving equation 2 below:
…Equation 2
It would be appreciated by those skilled in the art that the Equation 2 represented herein above is used for determining percent fuel contamination and soot contamination. For percent water contamination, AP i.e. kinematic viscosity measurement is replaced by dielectric constant obtained from the calibration relationship profiles. It would also be appreciated by those skilled in the art that the parameterization Equations 1 and 2 are linear and stable and auto-calibrating.
[0026] The contaminant dilution monitoring module 32 further includes an input module 46 configured for receiving multiple sensor measurements 48 for the one or more oil integrity measurands from the sensors 30 referred in FIG. 1. The multiple sensor measurements 48 are sent to an analysis module 50, that also receives calibration relationship profiles 42 and the one or more correction parameters 44 and is configured for generating multiple measurement profiles 52 based on the respective sensor measurements 48, applying the two or more correction parameters 44 on the measurement profiles 52 to generate a corrected relationship profile 54 for change of one or more fuel integrity measurands with respect to time, and for determining an amount of contaminant dilution 56 for one or more contaminants based on the corrected relationship profile 54.
[0027] The contaminant dilution monitoring module 32 also includes a communication module 60 configured for communicating the amount of contaminant dilution 56 to the controller 34 for initiating one or more control actions, that include, for example, generation of an alarm as an indication for oil change for the reciprocating engines based on the amount of contaminant dilution.
[0028] It would be understood by those skilled in the art that the different modules described in reference to contaminant dilution monitoring module 32 referred herein above are configured using a processor 62 and a memory 64. The processor 62 may include at least one arithmetic logic unit, microprocessor, general purpose controller or other processor arrays to perform computations, and/or retrieve data stored on the memory. In one embodiment, the processor may be a multiple core processor. The processor processes data signals and may include various computing architectures including a complex instruction set computer (CISC) architecture, a reduced instruction set computer (RISC) architecture, or an architecture implementing a combination of instruction sets. In one embodiment, the processing capability of the processor may be limited to supporting the retrieval of data and transmission of data. In another embodiment, the processing capability of the processor may also perform more complex tasks, including various types of feature extraction, modulating, encoding, multiplexing, and the like. Other type of processors, operating systems, and physical configurations are also envisioned.
[0029] In one embodiment, the memory 64 described herein above may be a non-transitory storage medium. For example, the memory may be a dynamic random access memory (DRAM) device, a static random access memory (SRAM) device, flash memory or other memory devices. The memory may also include a non-volatile memory or similar permanent storage device, and media such as a hard disk drive, a floppy disk drive, a compact disc read only memory (CD-ROM) device, a digital versatile disc read only memory (DVD-ROM) device, a digital versatile disc random access memory (DVD-RAM) device, a digital versatile disc rewritable (DVD-RW) device, a flash memory device, or other non-volatile storage devices.
[0030] Now turning to FIG. 3, a graphical representation of the calibration relationship profiles 42 referred herein above is presented. Curves in the set represented by 44 are soot curves for percent soot contamination between 0.1%- 4% and curves represented by 46 are fuel curves for percent fuel dilution between 1% to 6 %.
[0031] FIG. 4A is a graphical representation of the sensor measurement data 48 referred herein above. FIG. 4B is a graphical representation of measurement profiles 52 referred herein. FIG. 5A is a graphical representation 66 representing corrected relationship profile obtained by rotating the measurement profile 52 towards the calibration profile 42 as shown in FIG. 5B.
[0032] The aspects described herein above are also shown in FIG. 6 in a flowchart 70, illustrating a method for monitoring contaminant dilution (fuel, water or a combination of fuel and water) in lubricating oil for a reciprocating engine. The method includes a step 80, for generating calibration relationship profiles, for a change of one or more oil integrity measurands (with respect to time), such as viscosity and dielectric constant, for the lubricating oil. The method includes a step 90 for generating two or more correction parameters, based on the calibration relationship profiles. The method inlcudes a step 100 for receiving sensor measurements, for the one or more oil integrity measurands for the lubricating oil in the reciprocating engine. The method includes a step 110 for generating measurement profiles based on the sensor measurements. The method includes a step 120 for applying the two or more correction parameters, on the measurement profiles to generate a corrected relationship profile for change of one or more fuel integrity measurands with respect to time, as shown at step 130. The method then inlcudes a step 140 for determining an amount of contaminant dilution, for one or more contaminants, based on the corrected relationship profile; and a step 150 for generating an alarm, as an indication for oil change for the reciprocating engines based on the amount of contaminant dilution.
[0033] It would be further noted, that in accordance with another embodiment, a computer program application stored in non-volatile memory or computer-readable medium (e.g., register memory, processor cache, RAM, ROM, hard drive, flash memory, CD ROM, magnetic media, etc.) may include code or executable instructions that when executed may instruct and/or cause a controller or processor to perform method discussed herein above. The computer-readable medium may be a non-transitory computer-readable media including all forms and types of memory and all computer-readable media except for a transitory, propagating signal. In one implementation, the non-volatile memory or computer-readable medium may be external memory.
[0034] Thus, the method and system described herein above address the need for knowing more accurately, and timely, the percent dilution of the lubricating oil in the reciprocating engines for optimizing the engine life, thus allowing for an overall safer and more productive operation of the reciprocating engine, that is an important requirement for locomotives and other general purpose vehicles as well.
[0035] While only certain features of the disclosure have been illustrated and described herein, many modifications and changes will occur to those skilled in the art. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the disclosure.