58 research outputs found
Effect of DLC Coating on Tribological Behavior of Cylinder Liner-piston Ring Material Combination When Lubricated with Jatropha Oil
AbstractThe expansion of modern engines would have been unfeasible without advanced lubricant chemistry and proper lubricant formulation. Introduction of diamond like carbon (DLC) coatings opens further possibilities in improving performance of engine and transmission components, which cannot longer be achieved only by lubricant design.DLC coatings show extremely good promise for a number of applications in automotive components as they exhibit excellent tribological properties. In this paper, the tribological performance of hydrogenated amorphous carbon (a-C: H)DLC coating with Jatropha oil was evaluated using a four ball Tribometer also with commercial synthetic lubrication oil (SAE 40) used as base lubricant. Experimental results demonstrated that the hydrogenated amorphous carbon (a-C: H)DLC coating exhibited better performance with Jatropha oil in terms of wear and friction under similar operating conditions compared to the uncoated stainless. Thus, usage of hydrogenated amorphous carbon (a-C: H)DLC coating with Jatropha oil in the long run may have a positive impact on engine life
Experimental Investigation of Diesel Engine Performance, Combustion and Emissions Using a Novel Series of Dioctyl Phthalate (DOP) Biofuels Derived from Microalgae
Physico-chemical properties of microalgae biodiesel depend on the microalgae species and oil extraction method. Dioctyl phthalate (DOP) is a clear, colourless and viscous liquid as a plasticizer. It is used in the processing of polyvinyl chloride (PVC) resin and polymers. A new potential biofuel, hydrothermally liquefied microalgae bio-oil can contain nearly 11% (by mass) of DOP. This study investigated the feasibility of using up to 20% DOP blended in 80% diesel fuel (v/v) in an existing diesel engine, and assessed the performance and exhaust emissions. Despite reasonable differences in density, viscosity, surface tension, and boiling point, blends of DOP and diesel fuel were found to be entirely miscible and no separation was observed at any stage during prolonged miscibility tests. The engine test study found a slight decrease in peak cylinder pressure, brake, and indicated mean effective pressure, indicated power, brake power, and indicated and brake thermal efficiency with DOP blended fuels, where the specific fuel consumption increased. This is due to the presence of 16.4% oxygen in neat DOP, responsible for the relatively lower heating value, compared to that of diesel. The emission tests revealed a slight increase in nitrogen oxides (NOx) and carbon monoxide (CO) emissions from DOP blended fuels. However, particulate matter (PM) emissions were lower from DOP blended fuels, although some inconsistency in particle number (PN) was present among different engine loads
A Model of Technology Transfer in Japan's Rapid Economic Growth Period
Why did the Japanese economy stagnate before World War II, how did it achieve rapid economic growth after the war, and why did it stagnate again after the 1970s? To answer these questions, I developed a two-country trade model with technology transfer, where firms in a developed country (the U.S.) transfer technology to the competitors in a developing country (Japan) if it is profitable to do so and where the technology transfer is the engine of economic growth. In this model, among multiple equilibria, the equilibrium with low labor cost in Japan was chosen during the rapid growth period. Then, the firms in the developed country transferred technology to the firms in the developing country, resulting in rapid growth. However, during the other periods, the equilibrium with high labor cost in Japan was chosen, which caused stagnation. The model is quantitatively consistent with the per capita GDP relative to the U.S., the purchasing power parity-exchange rate ratio, and to some degree, the swings in labor share of postwar Japan
Sugarcane Biomass as a Source of Biofuel for Internal Combustion Engines (Ethanol and Acetone-Butanol-Ethanol): A Review of Economic Challenges
The objective of this review is to provide a deep overview of liquid biofuels produced from sugarcane bagasse and to address the economic challenges of an ethanol and acetone-butanol-ethanol blend in commercial processes. The chemistry of sugarcane bagasse is presented. Pretreatment technologies such as physical, chemical pretreatment, biological, and combination pretreatments used in the fermentation process are also provided and summarised. Different types of anaerobic bacteria Clostridia (yeast) are discussed to identify the ingredient best suited for sugarcane bagasse, which can assist the industry in commercializing ethanol and acetone-butanol-ethanol biofuel from biomass sugarcane. The use of an acetone-butanol-ethanol mixture and ethanol blend in internal combustion engines is also discussed. The literature then supports the proposal of the best operating conditions for fermentation to enhance ethanol and acetone-butanol-ethanol plant efficiency in the sugar waste industry and its application in internal combustion engines
Experimental investigation of tribological properties of laser textured tungsten doped diamond like carbon coating under dry sliding conditions at various loads
Laser micro texturing technique has shown its potential in reducing friction and wear at various mechanical interfaces
such as automotive and cutting tools etc. Automotive parts are coated with Diamond-like Carbon (DLC) coatings to
enhance their performance. Due to stringent condition at the automotive contacts and demand for performance
enhancement, increase in performance of DLC coatings is required. In this study laser micro texturing is being
combined with tungsten doped DLC coating. In order to analyze the benefits of laser micro texturing on tungsten
doped DLC coating. Tribological testing was conducted on a reciprocating test rig at various loading conditions. The
results indicated that laser textured tungsten doped DLC coating showed the lower coefficient of friction compared to
un-textured tungsten doped DLC coating at a load of 15 N, 25 N and 35 N. Higher graphitization was observed in the
case of un-textured coating at 35 N load
Role of Muscarinic Acetylcholine Receptors in Serial Feature-Positive Discrimination Task during Eyeblink Conditioning in Mice.
We investigated the role of muscarinic acetylcholine receptors (mAChRs) in eyeblink serial feature-positive discrimination learning in mice using the mAChR antagonist. A 2-s light cue was delivered 5 or 6 s before the presentation of a 350-ms tone paired with a 100-ms periorbital electrical shock (cued trial) but not before the tone-alone presentation (non-cued trial). Mice received 30 cued and 30 non-cued trials each day in a random order. We found that saline-injected control mice were successfully discriminating between cued and non-cued trials within a few days of conditioning. The mice responded more frequently to the tone in cued trials than in non-cued trials. Analysis of conditioned response (CR) dynamics revealed that the CR onset latency was shorter in cued trials than in non-cued trials, despite the CR peak amplitude not differing significantly between the two conditions. In contrast, scopolamine-injected mice developed an equal number of CRs with similar temporal patterns irrespective of the presence of the cue during the 7 days of conditioning, indicating in a failure to acquire conditional discrimination. In addition, the scopolamine administration to the control mice after they had successfully acquired discrimination did not impair the conditional discrimination and expression of pre-acquired CR. These results suggest that mAChRs may play a pivotal role in memory formation in the conditional brain state associated with the feature cue; however they are unlikely to be involved in the development of discrimination after conditional memory had formed in the serial feature-positive discrimination task during eyeblink conditioning
State-of-the-Art of Establishing Test Procedures for Real Driving Gaseous Emissions from Light- and Heavy-Duty Vehicles
Air pollution caused by vehicle emissions has raised serious public health concerns. Vehicle emissions generally depend on many factors, such as the nature of the vehicle, driving style, traffic conditions, emission control technologies, and operational conditions. Concerns about the certification cycles used by various regulatory authorities are growing due to the difference in emission during certification procedure and Real Driving Emissions (RDE). Under laboratory conditions, certification tests are performed in a ‘chassis dynamometer’ for light-duty vehicles (LDVs) and an ‘engine dynamometer’ for heavy-duty vehicles (HDVs). As a result, the test drive cycles used to measure the automotive emissions do not correctly reflect the vehicle’s real-world driving pattern. Consequently, the RDE regulation is being phased in to reduce the disparity between type approval and vehicle’s real-world emissions. According to this review, different variables such as traffic signals, driving dynamics, congestions, altitude, ambient temperature, and so on have a major influence on actual driving pollution. Aside from that, cold-start and hot-start have been shown to have an effect on on-road pollution. Contrary to common opinion, new technology such as start-stop systems boost automotive emissions rather than decreasing them owing to unfavourable conditions from the point of view of exhaust emissions and exhaust after-treatment systems. In addition, the driving dynamics are not represented in the current laboratory-based test procedures. As a result, it is critical to establish an on-road testing protocol to obtain a true representation of vehicular emissions and reduce emissions to a standard level. The incorporation of RDE clauses into certification procedures would have a positive impact on global air quality
Experimental investigation of essential oils in a diesel engine
The potential use of waste stream essential oils were evaluated as fuel supplements for diesel vehicle/machinery used by producers of these oils. Orange, eucalyptus and tea tree oils were selected; which are native to and/or extensively cultivated throughout Australia. These essential oils are mainly used in the medical and natural therapy sector as well as fragrance and flavouring industry. The high quality of the final product leads to a significant very low value waste stream. Engine performance and emissions evaluation showed that essential oils are comparable to diesel fuel. Their use will help to reduce diesel dependency and fuel costs
Exploring the Potential of Lignocellulosic Biomass-Derived Polyoxymethylene Dimethyl Ether as a Sustainable Fuel for Internal Combustion Engines
The most effective way to reduce internal combustion engine emissions is to use a sustainable alternative fuel that contains oxygen molecules. Alternative fuels may be used to address a future global energy crisis. Different oxygenated alternative fuels have been investigated in internal combustion engines. Polyoxymethylene di-methylene ether (PODE), which contains 3–5 CH2O groups, is currently superior in the field of oxygenated fuels due to its physical and chemical properties. Furthermore, using PODE as a fuel does not necessitate any significant engine modifications. When compared to standard diesel fuel, the use of PODE results in near stoichiometric combustion with less hazardous exhaust gas. It also significantly reduces NOx emissions due to the lack of C-to-C bonds. Several articles in the literature were found on the manufacturing and application processes for the production of PODE. However, the current review focuses primarily on simplifying the various production technologies, the physical and chemical properties of PODEn and its advantages and disadvantages in ICEs, PODEn application in internal combustion engines and its characteristics, PODE spray analysis, and measurements of the fuel’s physical and chemical characteristics. This review emphasizes the fact that PODE can be used as a sole fuel or in conjunction with fossil fuels and advanced combustion technologies. Because C-C bonds and higher oxygen molecules are not available, the trade-off relationship between nitrogen oxides and soot production is avoided when PODEn is used as a fuel, and combustion efficiency is significantly improved
Assessing idling effects on a compression ignition engine fueled with Jatropha and Palm biodiesel blends
In this study, performance of a diesel engine operated with Jatropha and Palm biodiesel blends at high idling conditions has been evaluated. The result obtained from experiment elucidate that, at all idling modes HC and CO emissions of both blends decreases, however, NO emissions increases compared to pure diesel fuel. Jatropha biodiesel has higher viscosity compared to Palm biodiesel, which might have degraded the spray characteristics and caused slightly improper mixing which might have led to slightly incomplete combustion, thus at both idling conditions, Jatropha blends emitted higher CO and HC compared to Palm biodiesels. Compared to diesel fuel, CO emissions were 5.9-9.7%, 17.6-22.6%, 23.5-29%, 2.9-6.4%, 5.9-14.5% and 11.8-17.74% less, HC emissions were 10.3-11.5%, 24.13-30.76%, 34.5-39%, 6.9-7.7%, 26-27% and 31-35% less and NOx emissions were 8.3-9.5%, 14-15%, 22-25%, 5-7.14%, 10-11.3% and 17-18% more respectively for 5, 10 and 20% blends of Palm and Jatropha biodiesel. Compared to diesel fuel, at high idling conditions brake specific fuel consumption all Palm and Jatropha biodiesel diesel blends increased. Compared to diesel fuel, BSFC were 1.14-1.35%, 2.28-2.96%, 7.1-8.35%, 2.28-2.69%, 3.98-5.39% and 8.83-9.29% more respectively for 5, 10 and 20% blends of Palm and Jatropha biodiesel
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