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The purpose of the Air Generation System is to provide a constant supply of conditioned fresh air to meet the necessary oxygen availability and to prevent carbon dioxide (CO2) concentrations for the occupants in an aircraft. The engine bleed energy or electrical load energy consumed towards this circumstance accounts to be approx. 5% of total fuel burn and in turn, contributes to the global emissions of greenhouse gases. This paper studies the improvement areas of the present conventional system such as fuel burn consumption associated with an aircraft environmental control system (ECS) depending on, the amount of bleed and ram air usage, electric power consumption. Improved systems for propulsion, power generation, sustainability, hybridization, and environmental control can be desirable for an aircraft.

Cabin Air quality is the measure of quality of air within the vehicle. Cabin air quality is not just important for comfort but for safety as well [1]. For decades, scientists have studied the air quality outside of automobiles. The in-cabin microenvironment has become a significant source of exposure to numerous air pollutants, such as particulate matter (PM), volatile organic compounds (VOCs), semi-volatile organic compounds (SVOCs), carbon monoxide, and nitrogen oxides, etc. [4]. There are various physical parameters such as filters, cabin temperature, air exchange rate, A/C ON or OFF condition and direction of flow of air inside the vehicle cabin, which can affect the cabin air quality and purification time. The air exchange and its rate being of highest importance [2]. The paper consists of various experimental results to check the effect of these parameters in improving the cabin air quality.

A parametric tool is developed to design general purpose and medium duty digging buckets for excavator. This is an excel based tool linked with CREO using VB API Toolkit feature of CREO. Critical parameters in determining lift ratio (such as vehicle tonnage, OEM bucket details, OEM maximum lift at full reach etc.) are defined as input parameters in the excel. Formulae set in this excel are used to calculate lift ratio which is used to determine if this newly developed bucket can be used with specified vehicle tonnage. It will auto generate 3D CAD model and 2D print in PDF format. This tool will also help to standardize the design process. Further, the developed 3D model is analyzed in ANSYS to check if stresses induced in bucket due to its working conditions are less than the material limit thereby assessing the robustness of design. Thus, it will help to reduce turnaround time for design iterations.

The useful life of an engine can be extended by reconditioning some of the components which are subjected to maximum wear and tear, lube pump is one such component. For a new gear pump, the clearance between the gear and casing is maintained at very low value to prevent leakage flows. As the engine comes to the end of its life the clearance increases due to wear and consequently a deterioration in pump performance is observed. A scientific methodology is required to find out the maximum clearance value up to which the pump can provide the target flow rate and head. This is done to assess whether a pump can be continued to be used or be replaced. Current method of qualifying the performance of the reconditioned pumps is through product testing, where pumps of different axial and radial clearances are tested to come up with acceptable clearance values. In this study, an attempt is made to replace testing with the CFD simulation to reduce the cost and time involved.

Automotive industries have been a significant contributor to global warming over the last 30 years. Due to the excessive increase in environmental degradation, research has been conducted extensively in various fields to explore sustainable alternatives to IC engines. Therefore, heavy emphasis is being laid on Battery-run Electric Vehicles (BEVs) and Fuel Cell Electric Vehicles (FCEVs). BEVs are facing their own set of challenges when it comes to production, recharge time, battery capacity and net carbon footprint, among other issues. However, FCEVs offer certain new opportunities for the automobile sector to foray into a sustainable space. This study aims to review the performance of fuel cell vehicles against the parameters of economic feasibility, technological feasibility, energy efficiency. Recent developments in fuel cell research have been discussed.

A spread sheet based parametric tool is developed to design the base frame for a marine generator-set. Factors such as engine details, generator details, anti-vibration mount (AVM) etc., that determine the design of the base frame, are set as parameters in the spreadsheet. The spreadsheet has formulae to calculate channel specifications, and AVM deflections. It is linked to channel standards database and selects the optimal channel based on calculations. Similarly, the tool provides guidance in selection of AVM from supplier catalogues, helps to predict number of anti-vibration mounts required and their location on base frame. This spread sheet is integrated with a generic base frame 3D model and 2D print in “Creo 3d modelling software” (Creo), which is auto-updated based on calculated parameters in the spreadsheet. Using this tool, the user can generate a 3D-model and 2D print. This tool helps to standardize the design process and reduces design turnaround time considerably.

The crankshaft translates the reciprocatory motion of the piston into rotary motion. A flywheel is generally connected to the crankshaft to reduce the vibrating characteristic of four stroke cycle. Counterweights are added for each reciprocating piston to provide engine balance while operating. Gasoline engines have curtailed compression ratio therefore shorter stoke length as a deduction have higher RPM in comparison to diesel counterpart. A crankshaft is subjected to enormous stresses, potentially equivalent of several tones of force. Failure of the crankshaft is predominantly due to violent vibrations, insufficient lubrication, excessively pressurized cylinder. This research aims to examine the stress subjected to acute points on a crankshaft. Three dimension model of 4 stroke single cylinder engine crankshaft is modeled using SolidWorks v18. End conditions were applied taking into consideration the engine mountings of the crankshaft.

This paper describes the methodology used to select an application-based fan that has optimum operating characteristics in terms of cooling air flow rate, fan power, and noise. The selected fan is then evaluated for structural strength. To evaluate different fans, complete rail coach under-hood simulations were carried out using steady-state 3D computational fluid dynamics (CFD) approach. These simulations considered an actual, highly non-uniform flow field. For each fan option, fan power, air flow rate, and surface acoustic power was evaluated. Pressure profiles on the fan blades were studied to assess the effect of non-uniform downstream air passage designs. Surface acoustic power was calculated using broadband noise source (BNS) model in ANSYS Fluent®. Surface pressure profiles over fan blades imported from 3D CFD were used in finite element analysis (FEA) in ANSYS. Analyses were carried out for blade linear and non-linear properties.

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.

Diesel engine widely uses in India in farming, transportation, and industrial sectors due to higher thermal efficiency, robust construction and heavy load carrying capacity. However, diesel engine emits a large number of gaseous emissions and particulate matter which caused serious detrimental environmental consequences and health hazards. The use of biofuel has shown a positive impact in resolving these issues of environmental degradation. India is also a net importer of petroleum-derived fuels and a substantial amount in precious foreign exchange is spent for this. In the last three decades in India, a lot of research work on renewable diesel-like fuels have been carried out, and the most promising of them is biodiesel. However,Biodiesel suffers from the drawback of relatively higher kinematic viscosity. But higher alcohols such as n-butanol and n-octanol could be blended with the biodiesel to bring its properties similar to diesel fuel.

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.

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.

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.

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.

Enhancement of combustion behavior of conventional liquid fuel using nanoscale materials of different properties is an imaginative and futuristic topic. This experiment is aimed to evaluate the performance and emission characteristics of a diesel engine when lade with nanoparticles of Cu-Zn alloy. The previous work reported the effect of metal/metal oxide or heterogeneous mixture of two or more particles; less work had been taken to analyze the homogeneous mixture of metals. This paper includes fuel properties such as density, kinematic viscosity, calorific value and performance measures like brake thermal efficiency (BTE), brake specific fuel consumption (BSFC) and emission analysis of NOX, CO, CO2, HC. For the same solid concentration, nano-fuel is compared with base fuel at different engine loads; and its effect when lade at different concentrations.

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.