Improving the Performance of Gas Engine Oils: A New Generation of Geo-Specific Additive Systems

2003 ◽  
Author(s):  
Laurent Chambard ◽  
John Smythe
Keyword(s):  
High Performance ◽  
Additive Technologies ◽  
Performance Limits ◽  
Base Oil ◽  
Gas Engine ◽  
Engine Oils ◽  
Base Oils ◽  
Beaten Track ◽  
Excellent Control ◽  
New Generation

Additive technologies able to successfully lubricate gas engines have been available for many years, but in recent years the acceleration of both commercial and technical demands placed on gas engine lubricants has highlighted the performance limits of traditional additive solutions. One of these limits is the ability to reach long and very long oil drains, required by an increasing number of operators. Since traditional additive chemistries on conventional base oil systems have reached their limits in that respect, focus has been increasingly placed on using higher performance base oils so that longer oil drains can be reached. However, traditional additive chemistries have often proved to struggle in these higher performance base oils, particularly in the aspect of deposit control — demonstrating that a new generation of additive systems for the formulation of gas engine oils is needed. The authors present one such generation of additive systems, developed around off-the-beaten-track detergent technology; providing superior control of oxidation and deposits. Such additive systems can be used either in conventional base oil systems with improved drain interval, or in high performance base oil systems with very long drain interval and excellent control of deposits. Besides the description of the chemistry involved, the authors also present a methodology of performance evaluation in the laboratory, and compare this methodology with the performance perceived in the field.

scholarly journals Review of Functional Treatments for Modified Wood

Coatings ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 327
Author(s):  
Morwenna J. Spear ◽  
Simon F. Curling ◽  
Athanasios Dimitriou ◽  
Graham A. Ormondroyd
Keyword(s):  
High Performance ◽  
Responsive Materials ◽  
Wood Modification ◽  
Wide Range ◽  
Natural Wood ◽  
Impregnation Modification ◽  
New Applications ◽  
New Generation ◽  
Dimensional Instability ◽  
Modified Wood

Wood modification is now widely recognized as offering enhanced properties of wood and overcoming issues such as dimensional instability and biodegradability which affect natural wood. Typical wood modification systems use chemical modification, impregnation modification or thermal modification, and these vary in the properties achieved. As control and understanding of the wood modification systems has progressed, further opportunities have arisen to add extra functionalities to the modified wood. These include UV stabilisation, fire retardancy, or enhanced suitability for paints and coatings. Thus, wood may become a multi-functional material through a series of modifications, treatments or reactions, to create a high-performance material with previously impossible properties. In this paper we review systems that combine the well-established wood modification procedures with secondary techniques or modifications to deliver emerging technologies with multi-functionality. The new applications targeted using this additional functionality are diverse and range from increased electrical conductivity, creation of sensors or responsive materials, improvement of wellbeing in the built environment, and enhanced fire and flame protection. We identified two parallel and connected themes: (1) the functionalisation of modified timber and (2) the modification of timber to provide (multi)-functionality. A wide range of nanotechnology concepts have been harnessed by this new generation of wood modifications and wood treatments. As this field is rapidly expanding, we also include within the review trends from current research in order to gauge the state of the art, and likely direction of travel of the industry.

scholarly journals A study on the numerical modelling of UHPFRC-strengthened members

2018 ◽  
Vol 199 ◽  
pp. 09001
Author(s):  
Renaud Franssen ◽  
Serhan Guner ◽  
Luc Courard ◽  
Boyan Mihaylov
Keyword(s):  
Numerical Modelling ◽  
High Performance ◽  
Concrete Structures ◽  
Concrete Members ◽  
High Durability ◽  
Tension Tests ◽  
The World ◽  
Aging Infrastructure ◽  
New Generation ◽  
Modelling Approach

The maintenance of large aging infrastructure across the world creates serious technical, environmental, and economic challenges. Ultra-high performance fibre-reinforced concretes (UHPFRC) are a new generation of materials with outstanding mechanical properties as well as very high durability due to their extremely low permeability. These properties open new horizons for the sustainable rehabilitation of aging concrete structures. Since UHPFRC is a young and evolving material, codes are still either lacking or incomplete, with recent design provisions proposed in France, Switzerland, Japan, and Australia. However, engineers and public agencies around the world need resources to study, model, and rehabilitate structures using UHPFRC. As an effort to contribute to the efficient use of this promising material, this paper presents a new numerical modelling approach for UHPFRC-strengthened concrete members. The approach is based on the Diverse Embedment Model within the global framework of the Disturbed Stress Field Model, a smeared rotating-crack formulation for 2D modelling of reinforced concrete structures. This study presents an adapted version of the DEM in order to capture the behaviour of UHPFRC by using a small number of input parameters. The model is validated with tension tests from the literature and is then used to model UHPFRC-strengthened elements. The paper will discuss the formulation of the model and will provide validation studies with various tests of beams, columns and walls from the literature. These studies will demonstrate the effectiveness of the proposed modelling approach.

Recent Advances in the Study of Film Cooling on the Gas Turbine Blade

2014 ◽  
Vol 971-973 ◽  
pp. 143-147 ◽  
Author(s):  
Ping Dai ◽  
Shuang Xiu Li
Keyword(s):  
Gas Turbine ◽  
Turbine Blade ◽  
Film Cooling ◽  
Gas Turbines ◽  
High Performance ◽  
Leading Edge ◽  
Development Trend ◽  
Research Progress ◽  
Gas Turbine Blade ◽  
New Generation

The development of a new generation of high performance gas turbine engines requires gas turbines to be operated at very high inlet temperatures, which are much higher than the allowable metal temperatures. Consequently, this necessitates the need for advanced cooling techniques. Among the numerous cooling technologies, the film cooling technology has superior advantages and relatively favorable application prospect. The recent research progress of film cooling techniques for gas turbine blade is reviewed and basic principle of film cooling is also illustrated. Progress on rotor blade and stationary blade of film cooling are introduced. Film cooling development of leading-edge was also generalized. Effect of various factor on cooling effectiveness and effect of the shape of the injection holes on plate film cooling are discussed. In addition, with respect to progress of discharge coefficient is presented. In the last, the future development trend and future investigation direction of film cooling are prospected.

Kinetic Study of the Thermo-Oxidative Degradation of Squalane (C30H62) Modelling the Base Oil of Engine Lubricants

2009 ◽  
Author(s):  
Moussa Diaby ◽  
Michel Sablier ◽  
Anthony Le Negrate ◽  
Mehdi El Fassi
Keyword(s):  
Oxidative Degradation ◽  
Engine Oil ◽  
Ongoing Research ◽  
Base Oil ◽  
Rate Law ◽  
Tert Butyl ◽  
Oxidation Rates ◽  
Base Oils ◽  
Wide Range ◽  
Thermo Oxidative Degradation

On the basis of ongoing research conducted on the clarification of processes responsible for lubricant degradation in the environment of piston grooves in EGR diesel engines, an experimental investigation was aimed to develop a kinetic model which can be used for the prediction of lubricant oxidative degradation correlated to endurance test conducted on engines. Knowing that base oils are a complex blend of paraffins and naphtenes with a wide range of sizes and structures, their chemistry analysis during the oxidation process can be highly convoluted. In the present work, investigations were carried out with the squalane (C30H62) chosen for its physical and chemical similarities with the lubricant base oils used during the investigations. Thermo-oxidative degradation of this hydrocarbon was conducted at atmospheric pressure in a tubular furnace, while varying temperature and duration of the tests in order to establish an oxidation reaction rate law. The same experimental procedures was applied to squalane doped with two different phenolic antioxidants usually present in engine oil composition: 2,6-di-tert-butyl-4-methylphenol (BHT), and octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (OBHP). Thus, the effect of both antioxidants on the oxidation rate law was investigated. Data analysis of the oxidized samples (FTIR spectroscopy, gas chromatography/mass spectrometry GC/MS) allowed to rationalize the thermo-oxidative degradation of squalane. The resulting kinetic modelling provides a practical analytical tool to follow the thermal degradation processes, which can be used for prediction of base oil hydrocarbon ageing. If experiments confirmed the role of phenolic additives as an affective agent to lower oxidation rates, the main results lay in the observation of a threshold temperature where a reversed activity of these additives was observed.

scholarly journals Performance Measures of Different Gate Oxide Materials in Gate All Around Fet

2020 ◽  
Vol 9 (2) ◽  
pp. 23-25
Keyword(s):  
High Performance ◽  
Field Effect Transistors ◽  
Gate Oxide ◽  
Oxide Semiconductor ◽  
Oxide Materials ◽  
Performance Limits ◽  
Short Channel ◽  
Advanced Technique ◽  
And Performance

The classical planar Metal Oxide Semiconductor Field Effect Transistors (MOSFET) is fabricated by oxidation of a semiconductor namely Silicon. In this generation, an advanced technique called 3D system architecture FETs, are introduced for high performance and low power quality of devices. Based on the limitations of Short Channel Effect (SCE), Silicon (Si) FET cannot be scaled under 10nm. Hence various performing measures like methods, principles, and geometrics are done to upscale the semiconductor. CMOS using alternate channel materials like GE and III-Vs on substrates is a highly anticipated technique for developing nanowire structures. By considering these issues, in this paper, we developed a simulation model that provides accurate results basing on Gate layout and multi-gate NW FET's so that the scaling can be increased few nanometers long and performance limits gradually increases. The model developed is SILVACO that tests the action of FET with different gate oxide materials.

scholarly journals The Investigation of Viscometric Properties of the Most Reputable Types of Viscosity Index Improvers in Different Lubricant Base Oils: API Groups I, II, and III

Lubricants ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 6
Author(s):  
Seyed Ali Khalafvandi ◽  
Muhammad Ali Pazokian ◽  
Ehsan Fathollahi
Keyword(s):  
Viscosity Index ◽  
Behavioral Differences ◽  
Base Oil ◽  
Polymer Molecules ◽  
Base Oils ◽  
Two Temperatures ◽  
Higher Temperature ◽  
Viscosity Index Improvers ◽  
Lower Temperature ◽  
Definition Of

Four commercial viscosity index improvers (VII) have been used to investigate the behavioral differences of these compounds in three types of universally applicable base oils. The used VIIs are structurally three types of co-polymer: ethylene-propylene, star isoprene, and two di-block styrene-isoprene. After dissolving of different amounts of VIIs in different base oils, the kinematic viscosities at two standard temperatures were determined and the intrinsic viscosities were calculated according to Huggins method, then the effects of changes in base oil and polymer type were investigated. Intrinsic viscosities as criteria for polymer molecules sizes were found to be higher at lower temperature than at higher temperature. Dependence of intrinsic viscosity on the polymer molecular weight was observed. In the previous works, one or two types of VIIs were studied in only one type of base oil and/or solvent, not different base oils. Furthermore, different ranges of temperatures and concentrations not necessarily applied ranges were selected, but in this work, common base oils and most commercial VIIs were used and the viscometric properties were compared at two temperatures. Viscosities at these temperatures are used for determining VI and definition of lubricant’s viscosity grades. VI improvement is the main cause of VII usage.

Sign in / Sign up

Export Citation Format

Share Document