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Many research centers and companies in general aviation have been devoting efforts to the electrification of propulsive plants to reduce environmental impact and/or increase safety. Even if the final goal is the elimination of fossil fuels, the limitations of today's battery in terms of energy and power densities suggest the adoption of hybrid-electric solutions that combine the advantages of conventional and electric propulsive systems, namely reduced fuel consumption, high peak power, and increased safety deriving from redundancy. Today, lithium batteries are the best commercial option for the electrification of all means of transportation. However, lithium batteries are a family of technologies that presents a variety of specifications in terms of gravimetric and volumetric energy density, discharge and charge currents, safety, and cost.

Effective contrail management while ensuring operational and economic efficiencies for flight services is essential for providing services with minimal adverse environmental impact. The paper explores various aspects of contrail management applicable to different platforms such as Unmanned vehicles, Commercial airliners and Business & regional jets. The aspects unique to each platform such as flight levels of operation, fuel types, flight endurance and radius of operation have been analyzed. Expanse of 5G network is resulting in increased flight activity at flight levels not envisaged hitherto. The paper also dwells on the ramifications of the increased proliferation of different platforms at newer flight levels from the perspective of contrail management.

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.

Battery electric vehicles are quickly gaining momentum to improve vehicle fuel efficiency and emission reduction. However, they must be designed to provide adequate range on a single charge combined with good acceleration performance, top speed, gradeability, and fast charging times. The paper presents a model for sizing the power train of an electric vehicle, including the power electronic converter, electric motor, and battery pack. A major assumption is that an optimal wheel slip rate can be achieved by modern vehicles using slip control systems. MATLAB/Simulink was used to model the vehicle powertrain. Simulations were conducted based on different speed and acceleration profiles. The purpose of the study focused on the motor and power electronics sizing requirements to achieve optimal range and performance.

The focus on driver and occupant safety as well as comfort is increasing rapidly while designing commercial vehicles in India. Improvements in the road network have enhanced road transport for commercial vehicles. Apart from the cost of operation and fuel economy, the commercial vehicles must deliver goods within stipulated time. These factors resulted in higher speed of operation for commercial vehicles. The design should not compromise the safety of the vehicle at these higher speeds of operation. The vehicle should obey the driver’s intended direction at all speeds and the response of the vehicle to driver input must be predictable without much larger surprises which can lead to accidents. The commercial vehicles are designed with rigid axle and RCB type steering system. This suspension and steering design combination introduce steering errors when vehicle travel over bump, braked and while cornering.

Electrification is getting more important in the aviation industry with the increasing need for reducing emissions of carbon dioxide and fuel consumption. It is crucial to assess the behavior of Li-Ion batteries at high-altitude conditions to design safe and reliable battery packs. This paper aims at benchmarking the performance of different formats of battery cells (pouch cells and cylindrical cells) in low-pressure environments. A test setup was designed and fabricated to replicate the standard procedure defined by the RTCA DO-311 standard, such as the altitude test and rapid decompression test. During the test voltage, current, temperature, and pressure were monitored, and the evaluation criteria is based on the capacity retention, along with the structural integrity of the cell. From preliminary tests, it was observed that cylindrical cells do not show a significant change in performance at low-pressure conditions thanks to their steel casing.

The aviation industry (passenger and freight), which currently accounts for 2.5% of the global CO2 emissions (1.9% of global greenhouse gas (GHG) emissions), is continuously under pressure to reduce its environmental footprint, given its historical and forecasted environmental track, strongly affected by the remarkable air traffic volume increase rates, albeit with a slower growth in emissions, due to the massive aviation's efficiency improvements, driven by the in the design and technology(more efficient and larger) aircrafts; improved operational practices and increased load factors (more passengers and freight per flight). Nevertheless, it has not been enough to tackle the rapidly increasing CO2 emissions (26% in the 2013-2018 timeframe and expected to continue increasing), which ultimately could grow between 2.4 and 3.6 times by 2050.

Fuel consumption of heavy-duty vehicles (HDV) is one of the major challenges in the automotive industry. In recent days, gasoline prices have been raised high, so the HDVs need to be designed to be more fuel-efficient. Many studies reported that aerodynamic optimization is one of the most important advancements in terms of fuel-efficient HDVs. The computational fluid dynamics (CFD) tool or approach is widely accepted for aerodynamic analysis. This study identifies the flow zones with the large pressure drag and design parameters, incorporating appropriate geometric changes into the design. The computational results show that the drag reduction of individual devices in cab and trailer is 15.9%. The cab deflector and boat tails are the most effective individual geometry and successfully reduce the drag up to 20%.

Aircraft traffic causes a significant amount of greenhouse gas emissions. Since modern aircrafts are highly electrified, the total weight is affected by cables within the components. Piezoelectric energy harvesting appears to be a reasonable option for reducing cables in certain parts of the aircraft and hence reducing fuel consumption. The proposed work covers energy harvesting in lightweight design with transmission mechanisms using so-called ferroelectrets. The energy harvester (EH) design is motivated by a strain-excitation in an aircraft wing caused by a quasi-stationary dynamic pressure. Ferroelectrets are piezoelectric polymers that show a higher ecological compatibility and a much higher structural flexibility than piezoceramics. Furthermore they provide charge constants in the same order of magnitude as piezoceramics.

The Range Rover Evoque is a compact luxury SUV, first introduced by Land Rover in 2012. Almost 800,000 units of the first-generation vehicle were sold. This paper explores some of the challenges entailed in developing the next generation of this successful product, maintaining key design cues while at the same time improving its aerodynamic efficiency. A development approach is outlined that made use of both numerical simulation and full-scale moving ground wind tunnel testing. A drag coefficient of 0.32 was obtained for the best derivative by paying particular attention to: the integration of active grille shutters; the front bumper and tyre package; brake cooling; underfloor design; wake control strategy; and detail optimization. This approach delivered the most aerodynamic Range Rover at the time of its introduction. The impact of these design changes on the aerodynamic flow field and consequently drag is highlighted.

In last few years there has been great research to increase safety of on-road vehicles by providing information of various vehicle parameters to the user/driver while driving on road. Many algorithms have been developed to assess the vehicle run time situations and enable vehicle ECU to take decisions for autonomous driving. These algorithms are derived using data captured from sensors predominantly make use of vehicle dynamic information. The design proposed in this paper discusses capturing of two important and critical vehicle run time parameters i.) Vehicle tire pressure and the ii.) Road gradient. These parameters then help us in determining the effective fuel efficiency of the vehicle and approximate distance that user can drive with the amount of fuel remaining in the tank.

Nowadays, E- commerce and logistics business model is booming in India with road transport as a major mode of delivery system using containers. As competition in such business are on rise, different ways of improving profit margins are being continuously evolved. One such scenario is to look at reducing transportation cost while reducing fuel consumption. Traditionally, aero dynamics of commercial vehicles have never been in focus during their product development although literature shows major part of total fuel energy is consumed in overcoming aerodynamic drag at and above 60 kmph in case of large commercial vehicle. Hence improving vehicle exterior aerodynamic performance gives opportunity to reduce fuel consumption and thereby business profitability. Also byproduct of this improvement is reduced emissions and meeting regulatory requirements.

In the present scenario, wherein the cost of transportation is continuously increasing, achieving optimum fuel efficiency is key area of focus for many Automotive OEMs. Aerodynamic drag is prominent form of resistance any vehicle encounters while it is in motion, and this particularly increases at higher speeds and exceeds all other forms of resistive forces acting on vehicle. Hence, predicting and improving aerodynamic performance of a car forms a very important aspect in overall product design cycle. Engineers and designers around the world try different methods for predicting and improving the aerodynamics of a car, including rigorous wind tunnel & test track testing. In current paper, we will be discussing a novel approach to predict and improve the aerodynamic drag for a test vehicle (Ford-Ka) model.

The trend of powertrain electrification is quickly spreading from the automotive field into many other sectors. For ultra-light aircraft, needing a total installed propulsion power up to 150 kW, the combination of a specifically developed internal combustion engine (ICE) integrated with a state-of-the-art electric system (electric motor, inverter and battery) appears particularly promising. The dimensions and weight of ICE can be strongly reduced (downsizing), so that it can operate at higher efficiency at typical cruise conditions; a large power reserve is available for emergency maneuvers; in comparison to a full electric airplane, the hybrid powertrain makes possible to fly at zero emissions for a much longer time, or with a much heavier payload. On the other hand, the packaging of a hybrid powertrain into existing aircraft requires a specific design of the thermal engine, that must be light, compact, highly reliable and fuel efficient.

Despite the continuous efficiency increase, traditional vehicles still dissipate large amounts of energy. While actual hybrid powertrains allow to recover kinetic energy during the braking phases, exhaust gas energy can be recovered through the electric turbo compound (ETC). A turbocharger (TC) match with an electric machine (EM) appears to be the best solution for passenger cars since it also permits turbo lag reduction with restricted system complexity increase. The goal of this paper is to investigate the TC electrification impact on fuel consumption, considering transient behavior during a whole drive cycle simulation. This is obtained coupling a detailed one-dimensional (1-D) engine model with vehicle dynamics and signal processing by means of sole GT-Suite software. A baseline engine refers to a 1.3 L, SI, 3-cylinder turbocharged engine while a class C vehicle is modelled.

Due to new CO2 regulations and increasing demand for improved fuel economy, reducing aerodynamic drag has become more critical. Aerodynamic drag at the rear of the vehicle accounts for approximately 40% of overall aerodynamic drag due to low base pressure in the wake region. Many studies have focused on the wake region structure and shown that drag reduction modifications such as boattailing the rear end and sharpening the rear edges of the vehicle are effective. Despite optimization using such modifications, recent improvements in the aerodynamic drag coefficient (Cd) seem to have plateaued. One reason for this is the fact that vehicle design is oriented toward style and practicality. Hence, maintaining flexibility of design is crucial to the development of further drag reduction modifications. The purpose of this study was to devise a modification to reduce rear drag without imposing additional design restrictions on the upper body.

Lane changing manoeuvers is an essential rudiment in vehicle driving and has a significant impact on the characteristics of traffic flow. In the case of traditional cars, the driver operates the vehicle to complete the lane change whilst for autonomous vehicles, completing the lane change requires planning the lane change trajectory and controlling the vehicle speed during the lane change. Unreasonable lane change trajectory and vehicle speed may cause the vehicle to lose stability, threaten driving safety, increase energy consumption and waste energy. This paper considers the safety and economy of the lane changing process, and proposes a new lane changing method for vehicles.

Having connectivity among ground vehicles brings about benefits in fuel economy improvement, traffic mobility enhancement and undesired emission reductions. On the other hand, Unmanned Aerial Vehicles (UAV) have proven to help in getting aerial data to end users in an affordable manner. When UAVs are equipped with cameras, they can get information about the terrain they are flying over. Moreover, using Vehicle-to-Everything (V2X) communication technologies, it is possible to form a communication link between UAVs and the connected ground vehicle networks comprising of Connected and Autonomous vehicles (CAVs). To investigate and exploit the potential benefits and use cases of a broad vehicle network, a microscopic traffic simulator modified previously by our group with the addition of nearby UAVs is used to integrate simulated Connected UAVs flying above a realistic simulation of heterogeneous traffic flow containing both CAVs and non-CAVs.

In order to achieve the purpose of saving energy and reducing emission, the improvement of aerodynamic performance plays an increasingly crucial role for car manufacturers. Previous studies have confirmed the validity of gradient-based adjoint algorithm for its high efficiency in shape optimization. In this paper, two important aspects of adjoint approach were explored. One is vehicle aerodynamic optimization with multiple objectives, and the other is using time-averaged flow results as the primal solution, both are issues of high interest in recent applications. First, adjoint shape optimization with steady-state and time-averaged flow simulations were respectively calculated and comparatively discussed based on a production SUV. The shape modifications of the two cases indicated that the impact of primal solution on design change could not be neglected, due to the different intrinsic codes of steady and transient turbulence models.

With the increasing adoption of electric vehicles in India, autos are also getting in the electrification race with lighter lithium-ion batteries and motor replacing the bulkier engine and transmission. This trend has led to a lighter vehicle which in-turn gives better mileage figures but at the loss of dynamic stability of the vehicle making them very unsafe. The current auto-rickshaws are using delta configuration that is more prone to the rollover while cornering. The three-wheeled configuration vehicle is less dynamically stable than the normal four-wheeled configurations. While working on prototype vehicle for Shell Eco-Marathon Asia [7] pro and cons for both configurations for a three-wheeled vehicle were considered and tadpole configuration was found to be more stable and better than current delta configuration.