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Dwindling petroleum reserves and alarming level of air pollution has been an issue of great concern in recent times and researchers across the world are experimenting on variety of renewable fuels for meeting the future energy demands. Within the gamut of alternative fuels, biofuels are the most promising and have the potential to mitigate climate change and lease a new life to existing IC engines. The vegetable oils are having immense potential in this context and have been used either in neat or modified form by large number of researchers. Jatropha curcus is a perennial plant and bears non edible oil. The plant is drought tolerant and has been cultivated all over the arid and semi-arid areas for reforestation. In the present study, blends of jatropha oil and ethanol have been prepared in 5, 10, 15 and 20% (v/v) and evaluation of important properties of blends has been carried. The results show that properties are quite similar to diesel fuel.

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.

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.

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.

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.

The increment in the application of fossil fuels is leading the world into a catastrophic state both environmentally and economically. Current demand for fuels exceeds its imminent supply and rather sooner than later energy demands will have to shift towards non-conventional fuels to cope with the situation. With constant developments in the automotive sector, several solutions have been found but none have been as good as gasoline to substitute it in the commercial market. One such solution being compressed air might solve this global fuel crisis, which serves a glowing advantage of being cheaper and greener as it produces zero tail-pipe emissions, and can help in decreasing automobile’s contribution to global warming. Though the potential energy stored in the compressed air limits its application to light duty vehicles and still there will be a need for other alternative solutions for the heavy duty vehicles in order to relieve the pressure from the fossil fuels.

Rapid depletion in fuel resources owing to the low efficiency of current automobiles has been a major threat to future generations for fuel availability as well as environmental health. Advanced new generation of internal combustion (IC) engines are expected to have far better emissions levels both gaseous (NOx and CO) and particulate matter, at the same time having far lower fuel consumption on a wide range of operating condition. These criteria could be improved having a homogeneous combustion process in an engine. Homogeneous mixing of fuel and air in HCCI leads to cleaner combustion and lower emissions. Since peak temperatures are significantly lower than in typical SI engines, NOx levels and soot are reduced to some extent. Because of absence of complete homogeneous combustion but quasi homogeneous combustion present in HCCI, there is still a possibility of further reducing the emissions as well as enhancing the engine performance.

Wind energy is clean and renewable source of energy that is an attractive alternative to non-conventional sources of energy. Due to rapid increase in global energy requirements, this form of energy is gaining its share of importance. Unlike nuclear power or tar sand oils, wind energy does not leave a long-term toxic legacy. Using MATLAB algorithms, multi-optimization of wind turbine design can be achieved. Therefore, an aerodynamic mathematical model is developed to obtain the optimal chord length and twist angle distribution along the blade span. Further, a promising generic blade design is used to initialize a detailed structure optimization wherein leading edge panel (LEP), Spar cap, Shear web, Trailing edge panel (TEP) reinforcement are sized using composite laminates so that the blade is according to the intended design standard. Initially blade airfoils are analyzed on 2D platform and then the results are used to construct 3D model of Horizontal Axis Wind Turbine (HAWT) blade.

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.

Internal combustion engines are the backbone of contemporary global transportation. But the major drawbacks associated with them, are the exhaust gases. These include carbon monoxide (CO), unburned hydrocarbons (UBHC), oxides of nitrogen (NOx), odor, particulate matter (PM) etc. Among them the emissions of oxides of nitrogen (NOx) and the particulate matter are the reasons of serious concern. For NOx reduction in recent developing technologies, diesel water emulsion was found the best approach for the existing engines by researchers. In the present study, performance and emission statistics of a diesel engine using diesel water emulsion operating at different compression ratios from 17:1 to 18:1 was performed. Stable Emulsions were prepared with 5%, 10%, 15%, 20% and 25 % (v/v) water concentration with variable agitation speed ranging from 5000-15000 rpm along with two surfactants. Various physico-chemical properties of emulsions were tested for all six samples including diesel.

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 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.

Biodiesel in has gained great momentum in last few years and has been a subject of vast research all around the globe. Bulk of the research work carried out so far has been confined to production of methyl esters of vegetable oil that is known as biodiesel in the transesterification process. In the present study, jatropha oil ethyl ester (JOEE) was prepared using transesterification process with ethanol and KOH as a catalyst. The evaluation of important physico-chemical properties was carried and the properties were found within acceptable limits of ASTM/EN standards. A small capacity diesel engine was fuelled with different blends of JOEE and diesel and various performances, emission and combustion characteristics were evaluated. The results suggested that brake thermal efficiency was increased and emissions of carbon monoxide, hydrocarbons and smoke opacity were found lower for JOEE blend confirming better combustion due to the oxygenated fuel and higher cetane rating.

In the present investigation AA6082/ SiC MMC composite is fabricated using electromagnetic stir casting technique. Silicon carbide (SiC) of 40 μm size is used as reinforcement and is varied by weight percentage as 0%, 2.5%, 5%, 7.5%, 10% in alloy AA6082. The microstructure of the fabricated composite is studied by scanning electron microscopy (SEM) which shows even distribution of the reinforcement. The mechanical properties improve with SiCp till 7.5%, after that the properties decreases which may be due to presence of porosity during the composite manufacturing. A comparative study of mechanical properties such as tensile strength, hardness and toughness has been done between the composite and base aluminium alloy. After the comparative study it was found that the composite having AA6082/SiC-92.5%/7.5% is best suited. So, it is used for optimization of Electrical Discharge Machining (EDM) process parameters using Taguchi’s design of experiment.

In the past few decades, use of energy resources in industrial and transportation sector have reached to its peak resulting in depleting resources and environment squalor. Vegetable oils, which have properties comparable to diesel fuel, are considered promising alternative fuels for unmodified diesel engines. However, high viscosity of vegetable oils is a major challenge which could be reduced by blending with alcohols. The aim of the present study was to investigate the suitability of orange peel oil and n-butanol blends as an alternative fuel for CI engine. Various blends of butanol with orange peel oil were prepared on volumetric basis and named as B10OPO90 (10% n-butanol and 90% orange peel oil), B20OPO80 (20% n-butanol and 80% orange peel oil), B30OPO70 (30% n-butanol and 70% orange peel oil) and B40OPO60 (40% n-butanol and 60% orange peel oil). All blends were found homogenous and various physico-chemical properties were evaluated in accordance to relevant standards.

Diesel engines are employed particularly in the field of heavy transportation and agriculture on account of their higher thermal efficiency and durability. As these engines, are the backbones of contemporary global transportation and accounts a 30% of world's energy consumption, which is second highest after the industrial sector. Therefore, the fossil fuel consumption becomes the prime concern. Following the global energy crisis and the increasingly stringent emission norms, the search for alternative renewable fuels has intensified. Currently, biodiesel (BD) has been identified as the most attractive and practical choice to replace fossil fuel as the main source of energy, due to the similarity in the properties with conventional diesel. However, its development and application have been hindered by the high cost of required feedstock. Therefore, in recent years, researchers have been seeking the alternative sources of non-edible oil which are economical.

The interest of using alternative fuels in diesel engines has been accelerated exponentially due to a foreseen scarcity in world petroleum reserves, increase in the prices of the conventional fossil fuels and restrictions on exhaust emissions such as greenhouse gases from internal combustion (IC) engines initiated by environmental concerns. The constant trade-off between efficiency and emissions should be in proper balance with the conventional fuels in a fuel design process for future combustors. Unlike gasoline and diesel, alcohols act as oxygenated fuels. Adding alcohols to petroleum products allows the fuel to combust properly due to the presence of oxygen, which enhances premixed combustion phase, improves the diffusive combustion phase which increases the combustion efficiency and reduces air pollution. The higher activation energy of alcohols leads to better resistance to engine knocking that allows higher compression ratios and greater engine thermal efficiencies.

Biodiesel production has been getting global awareness since Petroleum prices are escalating continuously. As biodiesel is gaining considerable demand, standards are vital for its commercialization and market introduction. Feedstocks availability has posed serious challenges, thus the need for non-edible and unexplored feedstocks has risen. In Indian context, Biodiesel is produced using sal seed oil which is potentially available in Indian forest as a non-edible feedstock. The present paper deals with the production optimization using design of experiments and fuel property characterization of Sal biodiesel (sal methyl esters). Transesterification process parameters like catalyst concentration (% w/w), Oil to Methanol molar ratio, reaction time (min) and reaction temperature (°C) were considered the significance factors and the response was taken as the Yield (% w/w). Experiment matrix with several combinations of factors was generated.

Increased demand and use of fossil fuels in transportation sector accompanied by the global oil crisis does not support sustainable development for the future generations to come. Not only that, today's on-road vehicles produce over one third of the CO and NOX present in our atmosphere and over twenty per cent of the global warming pollution. This air pollution carries significant risks for human health and the environment. Through clean vehicle and fuel technologies, it is possible to significantly reduce air pollution from our vehicles. In such a grim situation, Compressed Air Vehicles (CAV) powered by pressurized air stored in high pressure storage tanks seem to be one of the practical solutions available for tackling the fuel crisis and environment related issues.

Increased dependency on fossil fuels has led to its depletion as well as affected the environment adversely. Moreover, increasing crude oil prices is pressurizing vehicle manufacturers to invent new technology so as to increase fuel economy and at the same time to keep emissions under control. Hydrogen has gained popularity not just in terms of being an abundant alternative but also due to being a very clean propellant. In the present investigation, hydrogen boosting has been performed on an SI engine running on gasoline-methanol and ethanol-gasoline blends to determine the additional advantages of the same compared to pure gasoline operation. The engine selected for experimental analysis is a single cylinder, air cooled spark ignition engine that has been modified for hydrogen injection in the intake manifold prior to the port with the injection timing being held constant throughout the experiment.