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The Continuously Variable Transmission (CVT) is a widely adopted transmission system. The operation of a CVT is simple, but successfully foretelling the longitudinal motion of a vehicle that utilizes this transmission is sophisticated. As a result, different vehicles taking part in BAJA-SAE competitions were developed using various strategies to model the vehicle’s longitudinal dynamics and CVT operation. This article aims to provide a tool for obtaining a quantitative estimate of the longitudinal performance of a CVT equipped vehicle and for the selection of an optimal drive-train gear ratio for such a vehicle. To this end, this article proposes a novel, relatively simple, and reasonably accurate mathematical approach for modeling the longitudinal motion of a vehicle utilizing a CVT, which was developed by a novel integration of existing vehicle dynamics concepts.

Internal Combustion engines have been a significant component of the industrial development in the 20th and 21st centuries. However, the high working temperatures cause extensive wear and tear among the parts and results in a loss in fuel efficiency and ultimately seize the engine. To prevent this, there was a need for a cooling system. The current systems cool the vehicle's engine by transferring heat from the engine to the coolant/water in the water jacket from where it reaches the radiator via tubes, and the hot temperature coolant is cooled. This article proposes a change in the design of radiator fins to improve the overall cooling efficiency of such systems. As radiator fins are instrumental in the heat transfer process, a design change in them results in substantial changes in the output efficiency results. The central concept that is utilized is to increase the surface area of the fins, which would increase the rate of heat loss from the pipes.

While riding cycles, cyclists usually experience an aerodynamic drag force. Over the years, there has been a global effort to reduce the aerodynamic drag of a cycle. Fenders affect the aerodynamic drag of a cycle to a large extent, and fender coverage has a pronounced effect on the same. In this article, various fender coverage angles, varying from 60° to 270°, were studied to predict the aerodynamic drag with the help of a validated CFD model in SolidWorks Flow Simulation. The model was based on the Favre-Averaged Navier-Stokes (FANS) equations solved using the k-ɛ model. It was predicted that aerodynamic drag coefficient reduced fender coverage angle up to 135°, and thereafter started increasing. Analyses were carried out at velocities of 6 m/s, 8 m/s and 10 m/s and the results were found to be similar, with a minimum aerodynamic drag coefficient at 135° occurring in all the cases under study.

Lead (Pb) bronze material is used for the manufacturing of bearings. Lead provides less friction and wear-related properties to bronze. During working of the bearings the lead contained micro-chips mixes with the lubricant oil and makes its disposal difficult. Rotational speed and applied load are the two main parameters on which the working and amount of wear from the bearing depend. So it is important to find out an optimum set of speed and pressure on which a particular bearing should operate to minimize the wear and hence minimize the lead-contaminated lubricating oil. In the present work, Taguchi technique has been used to find out the optimum values of speed and pressure. To measure the specific wear rate (SWR) and coefficient of friction (COF) of the leaded bronze material, it is made to slide on a mild steel material and amount of wear and coefficient of friction has been recorded using a pin on disc machine using ASTM-G99 standards.

The power generation, agriculture, and transportation sectors are dominated by diesel engines due to better thermal efficiency and durability. Diesel engines are also a major contributor to the air pollutants such as NOx and particulate matter. Acetone-butanol-ethanol (ABE) is considered a promising alternative fuel as it emits less pollutants compared to conventional fuels. In current work, the ABE used was of the ratio (3:6:1) and four samples were prepared for engine trial ABE (10%90%diesel), ABE (20%80%diesel), ABE (30%70%diesel) and ABE (40%60%diesel). Their physio-chemical properties like kinematic viscosity, density, specific gravity and calorific value were checked and tested on compression ignition engine at different operating parameters. The experimental work was conducted upon Kirloskar 4-stroke single cylinder, vertical, air-cooled 661cc compression ignition engine at different speeds and loads.

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.

Biodiesel is a potential substitute for diesel and extensive research is carried in India on production and utilization of biodiesel from a variety of edible/non-edible, animal fat and waste oils. However, issues like stability, clogging, increased NOx, and high consumption rate etc. are some of the critical issues which are associated with long-term use of these alternative fuels in a diesel engine. The recent developments in science and technology may have concreted a method to create nano measure vigorous resources that have incredible benefits to micron sized constituents. Nano liquids may be a fresh period of compact-fluid complex constituents comprising of nano sized concrete elements disseminated into a base liquid. The present study investigates the effect of doping metal oxides nanoparticles with waste fish oil-based biodiesel. For the present study, the blends of fuel are prepared by using 30ppm each of titanium dioxide and alumina nanoparticles respectively.

Heat exchangers are widely used in various transportation, industrial, or domestic applications such as thermal power plants, means of heating, transporting and air conditioning systems, electronic equipment and space vehicles. In all these applications improvements in the efficiency of the heat exchangers can lead to substantial cost, space and material savings. Hence considerable research work has been done in the past to seek effective ways to improve the efficiency of heat exchangers. In this paper the effect of natural convection is justified between exterior solid wall surfaces and the surrounding air inside the enclosure. Designing of electronic devices, heavy industrial equipments such as boilers, turbines etc. and building aerodynamics are some of the real world application associated with this study.

Turboexpansion is a concept which is aimed at reducing the fuel consumption of pressure-charged combustion engines by providing over-cooled air to the engine prior to its induction in the combustion chamber. The performance of the engine is dependent on intake charge density which is preferred to be high at reduced charge air temperature. This becomes achievable through a cooling system known as a turbo expander which expands a high-pressure gas to produce work that is usually employed to drive a compressor. Though, initially used for the purpose of refrigeration in industries, for the past few decades various researches have proved its efficiency in internal combustion engines. In gasoline engines, it is usually employed to extend the knock limit and reduce carbon emissions. Also, an extension to the knock limit allows several improvements in parameters such as increased specific output, an increase in compression ratio and a reduction in the fuel consumption of the engine.

Study of starting friction during the running of the engineering application has an important role in designing them, especially working at low speed and high load conditions. A significant portion of research and development today is concentrated on saving the energy by reducing the friction. The present paper addresses the measurement technique and analysis of the starting friction during the running of the journal bearing. The experiments were performed during the hydrodynamic lubrication regime using SAE 15W-30 lubricating oil. A journal bearing having journal diameter as 22 mm, length/diameter ratio 1 and 0.027 mm radial clearance has been designed and fabricated to test the starting friction. Analysis of starting friction and average friction torque during the running of journal bearing was done at 900, 1150, 1400, 1650, 1900, 2150 and 2400 revolution per minute (rpm) speed of the journal at load values of 250, 400 and 500 N.

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.

Improving brake cooling has commanded substantial research in the automotive sector, as safety remains paramount in vehicles of which brakes are a crucial component. To prevent problems like brake fade and brake judder, heat dissipation should be maximized from the brakes to limit increasing temperatures. This research is a CFD investigation into the impact of existing wheel center designs on brake cooling through increased cross flow through the wheel. The new study brings together the complete wheel and disc geometries in a single CFD study and directly measures the effect on brake cooling, by implementing more accurately modeled boundary conditions like moving ground to replicate real conditions correctly. It also quantifies the improvement in the cooling rate of the brake disc with a change in wheel design, unlike previous studies. The axial flow discharge was found to be increased to 0.47 m3/min for the suggested design in comparison to 0.04 m3/min for traditional design.

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.

With the ever increasing number of vehicles on road and the rise of the electric and automated vehicles, it is important to minimize the consumption of energy by each vehicle, regenerative braking is in wide use today, however, the research in the field of regenerative suspension is limited. The regenerative suspension has huge capabilities in power generation especially on third world roads having rather bumpy rides. A huge amounts of energy is wasted in shock absorbers due to friction. This study emphasizes on the implementation of the energy present in the suspension system by replacing the Shock Absorber with a Energy transfer system Involving Hydraulic cylinder, Hydraulic Motor and Dynamo. The energy which is usually lost as heat due to friction in conventional Suspension is used to drive a dynamo through Hydraulic System designed in this paper and electricity is generated.

Dependency and increase in use of fossil fuels is leading to its depletion and raises serious environmental concerns. There are international obligations to reduce emissions and requirements to strengthen security of fuel supply which is pressuring the automobile industry to use cleaner and more sustainable fuels. Hydrogen fits these criteria as it is not just an abundant alternative but also a clean propellant and Hydrogen engines represent an economic alternative to fuel cells. In the present investigation, EGR has been used on hydrogen boosted SI engine running on gasoline-methanol and ethanol-gasoline blends to determine the additional advantages of the same compared to pure gasoline operation and gasoline-methanol and ethanol-gasoline blends without EGR.

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.

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.

Recent scenario of fossil fuel depletion as well as rising emission levels has witnessed an ever aggravating trend for decades. The solution to the problems has been addressed by investments and research in the field of fuels; such as the use of cleaner fuels involving biodiesel, alcohol blends, hydrogen and electric drivelines, as well as improvement in traditional technologies such as variable geometry systems, VVT load control strategies etc. The developments have highlighted the enormous potential present in such systems in terms of maximizing engine efficiency and emission reductions. The present paper aims at designing and implementing an intake runner system for a CI engine capable of providing flexibility with variations in operating conditions. Primarily, the design aims at altering the air flow phenomenon within the primary intake of the engine by inducing swirl in the runner through a secondary runner.

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 continued reliance on fossil fuel energy resources is not sufficient to cater to the current energy demands. The excessive and continuous use of crude oil is now recognized as unviable due to its depleting supplies and elevating environmental degradation by increased emissions from automobile exhaust. There is an urgent need for a renewable and cleaner source of energy to meet the stringent emission norms. Hythane is a mixture of 20% hydrogen and 80% methane. It has benefits of low capital and operating costs and is a cleaner alternative than crude oil. It significantly reduces tailpipe emissions and is the cheapest way to meet new emission standards that is BS-IV. Hythane produces low carbon monoxide (CO), carbon dioxide (CO2) and hydrocarbons (HC) on combustion than crude oil and helps in reduction of greenhouse gases.