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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 Continuously Variable Transmission (CVT) is a popular form of automotive transmission that uses friction between a belt and pulley to transmit power. Due to the sliding and other losses associated with the belt, power is lost in the form of heat, which must be dissipated to enhance the belt’s life. The task of heat dissipation is, however, complicated by the use of a CVT casing, which serves to protect the transmission from mud, debris, etc. Consequently, the design of an optimum CVT casing for efficient cooling is a challenging task. Experimental approaches or 3D numerical simulation approaches to tackling such problems are either involved or time-consuming or both. This article discusses a novel and simplified strategy for optimizing a CVT casing for maximum heat removal, using computational fluid dynamics (CFD). The rotating pulleys are approximated as heated, rotating cylinders inside a two-dimensional flow domain of the casing.

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.

Flow separation is one of the primary causes of increase in form drag in vehicles. This phenomenon is also visible in the case of lightweight vehicles moving at high speed, which greatly affects their aerodynamics. Spherical depressions maybe used to delay the flow separation and decrease drag in such vehicles. This study aims for optimization of aspect ratio (AR) of spherical depressions on hatchback cars. Spherical depressions were created on the bonnet of a generalized light vehicle Computer-Aided Design (CAD) model. The diameter of each spherical depression was set constant at 60 mm, and the center-to-center distance between consecutive spherical depressions is fixed at 90 mm. The AR of spherical depressions was taken as the parameter that was varied in each model. ARs 2, 4, 6, and 8 were considered for the current investigation. Three-dimensional (3D) CFD analyses were then performed on each of these models using a validated computational model.

Non-edible vegetable oils have a huge potential for biodiesel production and also known as second generation feedstock’s. Biodiesel can be obtained from edible, non-edible, waste cooking oil and from animal fats also. This paper focuses on production of biodiesel obtained from mixture of sesame (Sesamum indicum L.) oil and neem (Azadirachta indica) oil which are easily accessible in India and other parts of world. Neem oil has higher FFA content than sesame oil. Biodiesel production from neem oil requires pretreatment neutralization procedure before alkali catalyzed Trans esterification process also it takes large reaction time to achieve biodiesel of feasible yield. Neem oil which has very high FFA and sesame oil which has low FFA content are mixed and this mixture is Trans esterified with no pre-treatment process using molar ratio of 6:1.Fuel properties of methyl ester were close to diesel fuel and satisfied ASTM 6751 and EN 14214 standards.

Ever increasing consumption of petroleum derived fuels has been a matter of grave concern due to rapidly depleting global reserves and alarming levels of emissions leading to global warming and climate change. Exhaustive research has been carried out globally to evaluate the suitability of variety of renewable fuels for internal combustion engine applications. Amongst them, vegetable oil methyl esters or biodiesel seem to be a promising alternative for diesel in vital sectors such as transportation, industrial and rural agriculture. For quite some time, the focus for production of biodiesel has shifted towards non-edible oil feedstock from the edible ones, mostly due to food security issues. One such non-edible oil, locally known as Mahua in Indian subcontinent, is a very promising feed stock for biodiesel production. In the present investigation, 5%, 10%, 15% and 20% (v/v %) blends of mahua oil methyl ester (MOME) and diesel were prepared.

Concerns about long term availability of petroleum based fuels and stringent environmental norms have been a subject for deliberations around the globe. The vegetable oil based fuels and alcohols are very promising alternative fuels for substitution of diesel, reduce exhaust emissions and to improve combustion in diesel engines which is mainly possible due to oxygenated nature of these fuels. Jatropha oil is important non-edible oil in India which is either used in neat or modified form as diesel fuel. Furthermore n-butanol is renewable higher alcohol having properties quite similar to diesel fuel. In the present study, n-butanol was blended in Jatropha Oil (JO) and Jatropha Oil Methyl Ester (JME) on volumetric basis (10 and 20%). The blends were homogeneous and stable and there was no phase separation. The different physicochemical properties of blends were evaluated as per relevant standards.

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.

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.

The present world scenario faces a serious threat from increasing dependence on fossil fuels. This has triggered the awareness to find alternative energy as their sustainable energy sources. Biodiesel as a cleaner renewable fuel may be considered as a good substitution for diesel fuel due to it being used in any compression ignition engine without any modification. The main advantages of using biodiesel are its renewability and better quality of exhaust gas emissions. In terms of emissions from biodiesel, the cause of concern continues to be the NOx emissions. Therefore, to compliment the functioning of biodiesels, Urea-SCR over Cu-ZSM5 catalyst is an effective option due to its ability to convert NOx into nitrogen and water. There has been increasing concerns that biodiesel feedstock may compete with food supply in the long term. The recent paper focuses on use of two non-edible oils mahua oil and fish oil (processed from waste produced by fish).

For the last decade, the lubricant industry has been trying to formulate biodegradable lubricants with technical characteristics superior to those based on petroleum. A renewable resource, mahua oil, is good alternative to mineral oil because of its environmentally friendly, non toxic and readily biodegradable nature. The triacylglycerol structure of mahua oil is amphiphilic in character that makes it an excellent candidate as lubricant and functional fluid. It is also very attractive for industrial applications that have potential for environmental contact through accidental leakage, dripping or generates large quantities of after-use waste materials requiring costly disposal. Vegetable oil in its natural form has limited use as industrial fluids due to poor thermo-oxidation stability, low temperature behavior and other tribochemical degrading processes.

Drag and lift are the primary aerodynamic forces experienced by automobiles. In competitive automotive racing, the design of inverted wings has been the subject of much research aimed at improving the performance of vehicles. In this direction, the aerodynamic impact of change in maximum camber of the flap element and ground effect in a double-element inverted airfoil was studied. The National Advisory Committee for Aeronautics (NACA) 4412 airfoil was taken as the constant main element. The camber of the flap element was varied from 0% to 9%, while ground clearance was varied from 0.1c to 1.0c. A two-dimensional (2D) Computational Fluid Dynamics (CFD) study was performed using the realizable k-ε turbulence model in ANSYS Fluent 18.2 to analyze the aerodynamic characteristics of the airfoil. Parameters such as drag coefficient, lift coefficient, pressure distribution, and wake flow field were investigated to present the optimum airfoil configuration for high downforce and low drag.

Additive manufacturing has experienced rapid growth over a span of 25 years. Additive manufacturing involves the development of a three-dimensional (3D) object by stacking layer upon layer. Conventional machining techniques involve the removal of material. However, this technique differentiates itself from other techniques by means of addition of the material. The integration of CAD with additive manufacturing has offered the ability to create complex structures. Despite its clear benefits, additive manufacturing suffers from a high initial investment. An average cost of an entry level commercial 3D printer is 600$. A low-cost 3D printer has been designed and built for experimental investigation within a budget of 300$. The paramount process of 3D printing involves a combination of interpreting data from CAD files and controlling the motors using this data. The various design considerations while developing the 3D printer have been discussed.

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.

There has been a rapid increase in popularity of multipurpose All-terrain vehicles (ATV) across the globe over the past few years. SAE BAJA event gives student-community an opportunity to delve deeper into the nitty-gritty of designing a single seat, four-wheeled off road vehicle. The design and development methodology presented in this paper is useful in conceptualization of an ATV for SAE BAJA event. The vehicle is divided into various subsystems including chassis, suspension, drive train, steering, and braking system. Further these subsystems are designed and comprehensively analyzed in software like SolidWorks, ANSYS, WINGEO and MS-Excel. The 3-D model of roll cage is designed in SolidWorks and analyzed in ANSYS 9.0 for front, rear and side impact along with front and side roll-over conditions. Special case of wheel bump is also analyzed. Weight, wall thickness and bending strength of tubing used for roll cage are comprehensively studied.

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.

Unmanned Aerial Vehicles (UAVs) are becoming an effective way to serve humanitarian relief efforts during environmental disasters. The process of designing such UAVs poses challenges in optimizing design variables such as maneuverability, payload capacity and maximizing endurance because the designing of a BWB takes into account the interdependency between the stability and aerodynamic performance. The Blended Wing Body is an unconventional aircraft configuration which offers enhanced performance over conventional UAVs. In this study the designing of a BWB is investigated with an aim to achieve structurally sound and aerodynamically stable configuration. The design has been done by taking into consideration the side and top view airfoil for fuselage, because fuselage is a major lift generating portion in the UAV. For designing the control surfaces, the two major requirements for a controlled and safe flight of a UAV are its stability and maneuverability.

This study is an attempt to develop a decision support and control structure based on fuzzy logic for deployment of automotive airbags. Airbags, though an additional safety feature in vehicles, have proven to be fatal at various instances. Most of these casualties could have been avoided by using seat belts in the intended manner that is, as a primary restraint system. Fatalities can be prevented by induction of smart systems which can sense the presence and differentiate between passengers and conditions prevailing at a particular instant. Fuzzy based decision making has found widespread use due to its ability to accept non-binary or grey data and compute a reliable output. Smart airbags also allow the Airbag Control Unit to control inflation speed depending on instantaneous conditions.

The danger posed by climate change and the striving for securities of energy supply are issues high on the political agenda these days. Governments are putting strategic plans in motion to decrease primary energy use, take carbon out of fuels and facilitate modal shifts. Man's energy requirements are touching astronomical heights. The natural resources of the Earth can no longer cope with it as their rate of consumption far outruns their rate of regeneration. The automotive sector is without a doubt a chief contributor to this mayhem as fossil fuel resources are fast depleting. The harmful emissions from vehicles using these fuels are destroying our forests and contaminating our water bodies and even the air that we breathe. The need of the hour is to look not only for new alternative energy resources but also clean energy resources. Hydrogen is expected to be one of the most important fuels in the near future to meet the stringent emission norms.

In the present study, ethanol was added in lower proportions to non-edible vegetable oil “Schleichera oleosa” or “Kusum”, to evaluate various performance and emission characteristics of a single cylinder; diesel engine. For engine's trial, four samples were prepared with 5%, 10%, 15% and 20% ethanol in kusum oil (v/v) and the blends were named as E5K95, E10K90, E15K85 and E20K80 respectively. Neat Kusum oil was named as K100. The results indicated that brake thermal efficiency (BTE) was found to increase with increase in volume fraction of ethanol in the kusum oil. E5K95, E10K90, E15K85 and E20K80 test fuels exhibited maximum BTE of 25.4%, 26.4%, 27.4% and 27.7% respectively as compared to 23.6% exhibited by the neat Kusum oil. Similarly, full load brake specific energy consumption (BSEC) decreased from 16.3MJ/kWh in case of neat Kusum oil to 15.1MJ/kWh for E20K80 with an almost linear reduction pattern with increased ethanol composition in the test fuel.