Browse Topic: Engine lubricants
As the global energy transition moves to increased levels of electrification for passenger cars, then the number and role of hybrid electric vehicles (HEVs) increases rapidly. For these, the power reaches the road from an internal combustion engine (ICE) and/or an electric motor, with several switches between these three modes, over a typical drive-cycle. Consequently, this comes with a large increase in the number of significant engine stop and start events. Such events are potentially challenging for the HEV engine lubricant, as by comparison, for standard ICE cycles there is almost continuous relative movement of the two lubricated surfaces, for most areas of the engine. Based on both field and test cell observations, a challenging area for the lubricant within the gasoline direct injection (GDI) engine is the high pressure (HP) fuel pump, typically driven by a cam and follower, whilst lubricated by engine oil. From engine start, the speeds are low, also the fuel pump loads are high
This SAE Standard was prepared by Technical Committee 1, Engine Lubrication, of SAE Fuels and Lubricants Council. The intent is to improve communications among engine manufacturers, engine users, and lubricant marketers in describing lubricant performance characteristics. The key objective is to ensure that a correct lubricant is used in each two-stroke-cycle engine.
The information in this SAE Recommended Practice has been compiled by Technical Committee 1 (Engine Lubrication) of the SAE Fuels and Lubricants Division. The intent is to provide those concerned with the design and maintenance of two-stroke-cycle engines with a better understanding of the properties of two-stroke-cycle lubricants. Reference is also made to test procedures which may be used to measure the chemical and physical characteristics of these lubricants.
Shell Rotella hosted journalists at the National Tractor Pulling Championships in Bowling Green, Ohio, in August, where the company was sponsoring tractors run by Koester Racing in the mini-modified division. Karin Haumann, OEM technical manager of Shell Global Solutions, was onsite and spoke with TOHE about the approaching proposed category 12 (PC-12) heavy-duty diesel engine oil category. PC-12 engine oils are in development and will be licensed for use on January 1, 2027. The current engine oil categories, CK-4 and FA-4, were introduced in 2016. Development of the new category is necessary due to advancements in engine technology, and it aligns with stricter emissions regulations that begin in 2027, said Haumann, who serves as chairperson of the API new category development team. “As diesel engine technology evolves, they require oils that offer increased oxidation performance and wear reduction, can handle higher temperatures, and improve fuel economy,” she said. Lubricant
This SAE Standard defines the limits for a classification of engine lubricating oils in rheological terms only. Other oil characteristics are not considered or included.
In this paper, we present a novel algorithm designed to accurately trigger the engine coolant flow at the optimal moment, thereby safeguarding gas-engines from catastrophic failures such as engine boil. To achieve this objective, we derive models for crucial temperatures within a gas-engine, including the engine combustion wall temperature, engine coolant-out temperature, engine block temperature, and engine oil temperature. To overcome the challenge of measuring hard-to-measure signals such as engine combustion gas temperature, we propose the use of new intermediate parameters. Our approach utilizes a lumped parameter concept with a mean-value approach, enabling precise temperature prediction and rapid simulation. The proposed engine thermal model is capable of estimating temperatures under various conditions, including steady-state or transient engine performance, without the need for extra sensors. Moreover, it exhibits greater robustness compared to temperature estimation systems
This specification covers a fluorocarbon (FKM) elastomer that can be used to manufacture product in the form of sheet, strip, tubing, extrusions, and molded shapes. For molded rings, compression seals, molded O-ring cord, and molded-in-place gaskets for aeronautical and aerospace applications, use the AMS7259 specification.
Engine cold start is characterized by sub-optimal combustion efficiency due to the low temperature of the combustion chamber; this heavily increases engine raw emissions at start. One driving phenomenon is a limited fuel evaporation rate. Consequently, a liquid fuel film remains on the piston top at ignition. Liquid fuel deposited on the piston top is a well-known cause of “pool-fire”, leading to high levels of particle emissions; a problem particularly noticeable with bio-based renewable fuels. Engine piston pre-heating can be deployed to prevent or limit the formation of such fuel film and associated pollutants. In this work a practical technique is proposed to effectively pre-heat the pistons immediately before engine cold start. The device consists of a pressurized-heated oil buffer which pre-heats the pistons via the existing piston cooling nozzles. The device provides further benefits in emissions and fuel consumption in two ways: 1) the warm oil pre-lubricates the engine working
Assessing the functional quality of an engine lubricant through real-time sensing could pave the way for development of comprehensive engine health monitoring systems. In this study, a permittivity-based, commercial off-the-shelf (COTS) oil quality sensor was implemented in the lubricant flow of a diesel engine after detailed evaluation on a benchtop test facility. The sensor was mounted on the oil filter housing of the engine in the post-filter oil flow, and its implementation required no modifications to the engine block. Simultaneously, the lubricant flow was visualized by incorporating a novel test cell in the oil flow path. Both the sensor assembly and the flow visualization cell were fully characterized on the benchtop facility prior to implementation on the engine. In these experiments, fresh and used samples of the engine’s recommended oil were tested, and the sensor’s oil quality measurements showed noticeable differences between the engine and benchtop studies, a feature
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