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Diesel Engines are widely used in transportation, industrial and agriculture sectors worldwide due to their versatility and ruggedness. However, they also emit harmful emissions detrimental to human health and environment. Apart from environmental degradation, the perturbation in international crude oil prices is also mandating use of renewable fuels. In this context, vegetable oils such as Jatropha Curcas due to their carbon neutral nature and widespread availability, seems to present a promising alternative to the mineral diesel. Straight vegetable oils (SVO) are not recommended for direct diesel engine application due to their higher viscosity, poor volatility etc. and dilution of straight vegetable oil may effectively enable its direct application in unmodified diesel engines. In the present study, Jatropha oil was diluted with n-Butanol to improve the fuel properties of the blend.

The economics of operating internal combustion engines in cars, buses and other automotive equipment is heavily affected by friction and wear losses caused by abrasive contaminants. As such, dust is a universal pollutant of lubricating oils. Road dust consists of depositions from vehicular and industrial exhausts, tire and brake wear, dust from paved roads or potholes, and from construction sites. Present research investigates the influence of dust powder of size 5 μm-100 μm as contaminant in SAE 20W-40 lubricant on the relative motion of a plane surface over the other having circular surface in contact. A pin-on-disk setup as per ASTM G99 has been used to conduct the experiments, firstly at increasing rpm keeping constant load of 118 N, and secondly by increasing loads, keeping rpm constant at 1000. The contaminated lubricant has been used to study its influence on friction and wear rate at the interface of pin of 12 mm diameter and disk at track diameter of 98 mm.

The art and science of thrust vectoring technology has seen a gradual shift towards fluidic thrust vectoring techniques owing to the potential they have to greatly influence the aircraft propulsion systems. The prime motive of developing a fluidic thrust vectoring system has been to reduce the weight of the mechanical thrust vectoring system and to further simplify the configuration. Aircrafts using vectored thrust rely to a lesser extent on aerodynamic control surfaces such as ailerons or elevator to perform various maneuvers and turns than conventional-engine aircrafts and thus have a greater advantage in combat situations. Fluidic thrust vectoring systems manipulate the primary exhaust flow with a secondary air stream which is typically bled from the engine compressor or fan. This causes the compressor operating curve to shift from the optimum condition, allowing the optimization of engine performance. These systems make both pitch and yaw vectoring possible.

The use of alternative fuel has many advantages and the main ones are its renewability, biodegradability with better quality exhaust gas emission, which do not contribute to raise the level of carbon dioxide in the atmosphere. The use of non-edible vegetables oils as an alternative fuels for diesel engine is accelerated by the energy crisis due to depletion of resources and increase in environmental problems. In Asian countries like India, great need of edible oil as a food so cannot use these oils as alternative fuels for diesel engine. However there are many issues related to the use of vegetable oils in diesel engine that is high viscosity, low calorific value, high self-ignition temperature etc. Jatropha curcas has been promoted in India as a sustainable substitute to diesel fuel. This research prepared micro emulsions of ethanol and Jatropha vegetable oil in different ratio and find out the physico-chemical parameters to compare with mineral diesel oil.

In view of the rapid depletion, increasing prices and uneven distribution of conventional petroleum fuels; the interest in the use of alternative fuels has increased exponentially. Fuels such as biodiesel & alcohol have been evaluated both at experimental and commercial scale due to improved emission characteristics as compared to conventional fuels. Alcohols are oxygenated and result in improving the engine performance. As a blend with conventional gasoline, the alcohols enhance the premixed and diffusive combustion phase which improves the combustion efficiency. The present investigation evaluates studies on stability and homogeneity along with physicochemical properties like density, viscosity, calorific value, copper-strip corrosion and solubility at room temperature of Propan-2-ol and gasoline blends. Comprehensive engine trials on unmodified petrol engine fuelled with blends of Propan-2-ol and gasoline blends in the proportions of 5, 10, 15 and 20% by volume have been conducted.

The present study was carried to explore the potential suitability of biodiesel as an extender of Kerosene in an off road dual fuel (gasoline start, kerosene run) generator set and results were compared with kerosene base line data. The biodiesel was blended with kerosene in two different proportions; 2.5% and 5% by volume. Physico-chemical properties of blends were also found to be comparable with kerosene. Engine tests were performed on three test fuels namely K100 (Kerosene 100%), KB 2.5 (Kerosene 97.5% + Biodiesel 2.5%) and KB5 (Kerosene 95% + Biodiesel 5%). It was found that brake thermal efficiency [BTE] increases up to 3.9% while brake specific energy consumption [BSEC] decreases up to 2.2% with increasing 5% volume fraction of biodiesel in kerosene. The exhaust temperature for blends was lower than kerosene. The test engine emitted reduced Carbon monoxide [CO] emission was 7.4 % less than using neat kerosene as compared to kerosene-biodiesel blends.

Biodiesel from non-edible vegetable oils is of paramount significance in India due to insufficient edible oil production. The present work deals with relatively underutilized non-edible oil “Schleichera oleosa” or “Kusum”. The Kusum biodiesel (KB) was produced using a two stage esterification cum transesterification process as the free fatty acid content of the oil was high. Important physico-chemical properties were evaluated and they were found to conform with corresponding ASTM/EN standards. Various test fuels were prepared for the engine trial by blending 10%, 20%, 30% and 40% of KB in diesel by volume and were named as KB10, KB20, KB30 and KB40 respectively. The results showed that full load brake thermal efficiency was dropped by 3.8% to 17% with increase in KB composition in the test fuel. Diesel (D100) showed the maximum full load brake specific energy consumption followed by KB10, KB20, KB30 and KB40.

Internal combustion engines are extensively used in every field of life in today's world. Diesel engines being more efficient are preferred in the industrial and transportation sector in comparison to spark ignition engines for their higher efficiency, versatility and ruggedness. The major emissions of diesel engines are oxides of nitrogen (NOx), particulate matter (PM), carbon dioxide (CO2), carbon monoxide (CO). Among these emissions, oxides of nitrogen (NOx) and the particulate matter are the reasons of serious concern. For reduction of oxides of nitrogen (NOx) and particulate matter simultaneously, the use of Homogeneous Charge Compression Ignition (HCCI) have provided a sustainable solution in the present scenario. Further, the use of CNG in HCCI engine along with pilot diesel injection; the emissions have been decreased drastically. Homogeneous mixing of fuel and air leads to cleaner combustion and lower emissions.

The growing energy demand and limited petroleum resources in the world have guided researchers towards the use of clean alternative fuels like alcohols for their better tendency to decrease the engine emissions. To comply with the future stringent emission standards, innovative diesel engine technology, exhaust gas after-treatment, and clean alternative fuels are required. The use of alcohols as a blending agent in diesel fuel is rising, because of its benefits like enrichment of oxygen, premixed low temperature combustion (LTC) and enhancement of the diffusive combustion phase. Several researchers have investigated the relationship between LTC operational range and cetane number. In a light-duty diesel engine working at high loads, a low-cetane fuel allowed a homogeneous lean mixture with improved NOx and smoke emissions joint to a good thermal efficiency.

The increasing rate of fossil fuel depletion and large scale debasement of the environment has been a serious concern across the globe. This twin problem of energy crises has caused researchers to look for a variety of solutions in the field of internal combustion engines. In this current scenario the issue of fuel availability has increased the use alternative fuels, especially alcohol derived fuels. Alcohol-diesel blends can be been seen as a prominent fuel for CI engine in the near future. Previous research on the use of alcohol as an alternative fuel in CI engines is restricted to short branch alcohols, such as methanol and ethanol. Despite their comparable combustion properties longer chain alcohols, such as butanol, isobutanol and pentanol have been barely investigated. In the present study performance and emission characteristics of an isobutanol-diesel blend was studied. One of the major problems encountered by isobutanol in CI engines is its low cetane rating.

The diesel engine has for many decades now assumed a leading role in both the medium and medium-large transport sector due to their high efficiency and ability to produce high torque at low RPM. Furthermore, energy diversification and petroleum independence are also required by each country. In response to this, biodiesel is being considered as a promising solution due to its high calorific value and lubricity conventional petroleum diesel. However, commercial use of biodiesel has been limited because of some drawbacks including corrosivity, instability of fuel properties, higher viscosity, etc. Biodiesel are known for lower CO, HC and PM emissions. But, on the flip side they produce higher NOx emissions. The addition of alcohol to biodiesel diesel blend can help in reducing high NOx produced by the biodiesel while improving some physical fuel properties.

Globally, transportation is the second largest energy consuming sector after the industrial sector and is completely dependent on petroleum products and alternative technologies. So, fossil fuel consumption for energy requirement is a primary concern and can be addressed with the fuel consumption reduction technologies. Transportation sector is mainly using diesel engines because of production of high thermal efficiency and higher torque at lower RPM. Therefore, diesel consumption should be targeted for future energy security and this can be primarily controlled by the petroleum fuel substitution techniques for existing diesel engines. Some of the fuel, which includes biodiesel, alcohol-diesel emulsions and diesel water emulsions etc. Among which the diesel water emulsion (DWE) is found to be most suitable fuel due to reduction in particulate matter and NOx emission, besides that it also improves the brake thermal efficiency.

The behavior of flow over an automobile’s body has a large effect on vehicle performance, and automobile manufacturers pay close attention to the minimal of the details that affect the performance of the vehicle. An imbalance of downforce between the front and rear portion of the vehicle can lead to significant performance hindrances. Worldwide efforts have been made by leading automobile manufacturers to achieve maximum balanced downforce using aerodynamic elements of vehicle. One such element is the front splitter. This study aims to analyze the aerodynamic performance of automobile at various splitter overhang lengths using Computational Fluid Dynamics (CFD). For the purpose of analysis, a three-dimensional (3D) CFD study was undertaken in ANSYS Fluent using the realizable k-ε turbulence model, based on the 3D compressible Reynolds-Averaged Navier-Stokes (RANS) equations.

The energy crisis coupled with depleting fuel reserves and rising emission levels has encouraged research in the fields of performance enhancement, emission reduction technologies and engineering designs. The present paper aims primarily to offset the problem of high emissions and low efficiencies in low cost CI engines used as temporary power solutions on a large scale. The investigation relates to the low cost optimization of an intake runner having the ability to vary the swirl ratio within the runner. Test runs reveal that NOx and CO2 follow a relatively smaller gradient of rise and fall in their values depending on the configuration; whereas UHC and CO have a rapid changes in values with larger gradients. However, in a relative analysis, no configuration was able to simultaneously reduce all emission parameters and thus, there exists a necessity to find an optimized configuration as a negotiation between the improved and deteriorated parameters.

In the present experimental investigation, performance, emission and combustion characteristics of a single cylinder diesel engine using diesel-biodiesel blends and antioxidant containing biodiesel test fuels was carried out. The potential suitability of aromatic amine based antioxidants to enhance the oxidation stability of biodiesel on one hand and reduction of tail pipe oxides of nitrogen (NOx) on the other were evaluated. Tertiary Butyl Hydroquinone (TBHQ) was considered as the antioxidant and Calophyllum Inophyllum vegetable oil was taken as the feedstock for biodiesel production. The test fuel samples were neat diesel (D100), 10% and 20% blend of Calophyllum biodiesel with diesel (CB10 and CB20) and 1500 ppm of TBHQ in CB10 and CB20 (CBT10 and CBT20). The results indicated that neat biodiesel blended test fuels (CB10 and CB20) exhibited lower brake thermal efficiency compared to the diesel baseline by a margin of 3% to 10% at full load.

The functions of a piston ring are to seal off the combustion pressure, to distribute and control the oil, to transfer heat and to stabilize the piston. Most piston rings and metallic sealing rings for modern application where running conditions are severe, require some form of coating to minimise abrasion and corrosion. The piston ring coating improves the life of engine as well as fuel efficiency. In this study, physical vapour deposition (ion chrome plating) was investigated; plates with similar composition as the piston ring material were prepared by the casting process using induction arc furnace and sand mould. Wear test of the coating was conducted on pin on disc machine under dry conditions. The wear rate was calculated using mass loss methods on an electronic balance having least count of 1× 10−4 g.

The Aerofoil theory along with its design has integrated itself into the vast areas of applications ranging from Automobile, Aeronautical, Wind Turbine, Micro-Vehicles, UAVs applications. In this paper, knowing the intricacy of the airfoil's applications, A MATLAB Code for NACA-2415 Airfoil is developed and a Model with dimensions c=180mm, w=126mm, tmax=27mm is generated. The model is then subjected to Flow Simulation with various input parameters: Reynolds Numbers taken are- (REN-1) 105 and (REN-2) 2×105 [Laminar External Flow], Angles of attack taken are-0°, 4°, 8°, 12°. The pressure and velocity distribution along the airfoil sketch curve are graphed qualitatively, emphasizing on the flow separation leading to the transition from laminar to turbulent flow. The various aerodynamics characteristic curves for coefficient of pressure, coefficient of lift and coefficient of drag are plotted against different angle of attacks for REN-1 and REN-2.

Friction stir processing (FSP) is a method of changing the properties of metal through intense, localized plastic deformation. This deformation is produced by forcibly inserting a non-consumable tool into a workpiece, and revolving the tool in a stirring motion as it is pushed laterally through the workpiece. It comprises of a rotating tool with pin and shoulder which are inserted into a single piece of material and traversed along the desired path to cover the region of interest. Friction between the shoulder and work piece results in localized heating which raises the temperature of the material to the range where it is plastically deformed. During this process, severe plastic deformation occurs and due to thermal exposure of material, it results in a significant evolution in the local microstructure. Carbon nanotubes were dispersed into Al matrix by multipass FSP to fabricate Al6082 T0/Fe-MWCNT.

Metal matrix composites have a large range of applications in the automobile industry due to its characteristics and properties. Al-based MMC have aluminum as matrix metal that has properties which are well concerned with the automobile industry. Some of these properties are high strength to weight ratio and lightweight. In this paper we are trying to develop aluminum-based metal matrix composite (MMC) reinforced with natural fibers ashes, we are using fine ashes of Sugarcane (bagasse), Groundnut Shell Ash (GSA), Rice Husk Ash (RHA) and Coconut shell (Jute) ash, different effects are investigated for different percentage of reinforcing material which is being produced by burning in a free atmosphere. Ball milling is used for making fine particle size of different natural fibers ash. Nine samples were made by the stir casting process consisting of Al6063 as base metal and different concentration of reinforcement.

Gasoline has been the major fuel in transportation, its good calorific value and high volatility have made it suitable for use in different injection methods. The drastic increase in use of carbon based fuels has led to increase in harmful emissions, thus resulting in implementation of stricter emissions norms. These harmful emissions include carbon monoxide and NOx. To meet the new norms and reduce the harmful emissions, better techniques have to be implemented to achieve better combustion of gasoline and reduce the amount of carbon monoxide in the exhaust. One such way of doing this is by enriching gasoline with hydrogen. Due to its low activation energy and high calorific value, the high energy released from hydrogen can be used to achieve complete combustion of gasoline fuel. However, there are certain drawbacks to the use of hydrogen in spark ignition engine, knocking and overheating of engine parts being the major problems.