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Considerable weight of an automobile is constituted by the engine and there is scope for improvement in fuel efficiency and emission control through optimization of weight in the engine. In this work, AlSi10Mg alloy produced by the direct metal laser sintering (DMLS) is suggested for engine application which is a lightweight aluminum alloy. Mechanical properties like tensile strength, compressive strength, and hardness of both cast and DMLS manufactured alloy are compared followed by analysis of SEM images of tensile test fractured surfaces. Reciprocating wear test is carried out for one lakh cycles at 125°C temperature with SAE 40 grade oil as lubricant. Co-efficient of friction (COF), wear rate of the cast and DMLS manufactured samples are compared. Wear patterns are analyzed using SEM images of the wear tracks.

Vehicle aerodynamic drag reduction is the effective technique to enhance the fuel economy, performance and top speed of a vehicle. Out of the total drag, the underbody drag contributes about 40-50% by the parts like wheel arch, wheel housing, and the wheels. This further increases in the case of vehicles with higher CG. Thus, it seems logical to focus attention on the underbody aerodynamic drag reduction. In this study, an active spoiler is placed towards the front end of the vehicle which will divert the air flow from the front towards the radiator. The active spoiler revolves according to the signals received from the radar sensors placed at the lower end to detect obstacles which will prevent it from damage. The aim of the study is to examine the effect of the air flow diversion on underbody drag. The effect of air flow diversion on fuel consumption, radiator effectiveness and top speed is numerically evaluated.

The objective of this study is to develop, demonstrate and validate the methodology of external aerodynamic analysis of a State Road Transport bus for prediction of drag coefficient and its impact on fuel consumption with experimental validation. It has been verified that vehicle consumes around 40% of the available engine power to overcome the air drag. This gives us a huge scope to study the effect of aerodynamic drag. Baseline model of State Road Transport Bus was evaluated for estimating fuel consumption using Computational Fluid dynamics (CFD) methodology. The CFD results were validated with the experimental data with less than 10% deviation. Bus design was optimized with an objective of reducing the fuel consumption with parameters like angle of windshield, rounding and tapering corners and rear draft angle. Optimized bus design is also ensured to meet functional specifications as per AIS052.

Rising energy demands, ecological deterioration and diminution of fossil fuels has necessitated the researchers to search for alternatives. With alternate fuels like Liquefied Petroleum Gas (LPG), hydrogen and alcohol based fuels, it is easier to substitute with the present engine without many alterations. Excellent chemical properties of these fuels make them favorable for lean burn operation which makes it a cost effective option to achieve goals of better fuel economy and controlled emissions. In this regard, experimental studies were carried out to examine the effects of LPG with different proportions of alcohols like ethanol and methanol (5, 10 and 20%) on the performance, emission and combustion characteristics of a single cylinder SI engine operated at a constant speed of 1500 rpm with a optimized compression ratio of 10.5:1 under full throttle opening conditions at varying equivalence ratio.

The heat losses through exhaust gases and the engine coolant contribute significantly towards reduction in thermal efficiency of an Internal Combustion (IC) engine. This largely impacts the fuel economy and power output. Waste Heat Recovery (WHR) has proven to be an effective method of overcoming these challenges. A Rankine cycle is a reverse refrigeration cycle that circulates a working fluid through the four basic components namely the pump, evaporator, turbine and condenser. It is a popular WHR approach in automotive applications with varying levels of success in the past. As the heat transfer capability in organic working fluids is greater than the conventionally used inorganic fluids, the former is used to capture maximum waste heat from low grade heat sources such as the automobile engine. A dual-loop Organic Rankine Cycle (ORC) is proposed for a heavy duty IC Engine with working fluids R245fa and R236fa for the High Temperature (HT) and Low Temperature (LT) loops respectively.