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Abstract More than a decade ago, we proposed combined use of direct injection (DI) and jet ignition (JI) to produce high efficiency, high power-density, positive-ignition (PI), lean burn stratified, internal combustion engines (ICEs). Adopting this concept, the latest FIA F1 engines, which are electrically assisted, turbocharged, directly injected, jet ignited, gasoline engines and work lean stratified in a highly boosted environment, have delivered peak power fuel conversion efficiencies well above 46%, with specific power densities more than 340 kW/liter. The concept, further evolved, is here presented for unmanned aerial vehicle (UAV) applications. Results of simulations for a new DI JI ICE with rotary valve, being super-turbocharged and having gasoline or methanol as working fuel, show the opportunity to achieve even larger power densities, up to 430 kW/liter, while delivering a near-constant torque and, consequently, a nearly linear power curve over a wide range of speeds.

The 12 papers in this technical paper collection are devoted to experimental and numerical investigations in the area of fuel injection systems and sprays in both spark ignition and compression ignition engines. Topics include spray geometry characterization, fuel atomization, optical diagnostic techniques, and fuel effects.

This technical paper collection will cover conceptual, modeling and experimental studies relating to advanced turbochargers/superchargers and advanced boosting systems to achieve increased power density, better fuel economy, and reduced emissions.

This technical paper collection covers powertrain control processes related to achieving stringent market fuel economy, emissions, performance, reliability, and quality demands of hybrid and electric powertrains. Topics include the control, calibration, and diagnostics of the engine, powertrain, and supporting electromechanical subsystems related to energy management.

The 26 papers in this technical paper collection focuses on kinetically controlled combustion including, HCCI, PCCI, CAR, RCCI, etc.

Over the past several years the FZG A/8.3/90 test method has been used to evaluate current qualified aviation lubricants. The results of the effort have been summarized in this document as a historical reference to document the findings made from the committee.

The E-36 committee is requested to develop a standard or recommended practice for Control System Fault Accommodation to provide guidance on the fault detection and accommodation strategies and robust validation toward certification to FAA Control System regulation 33.28. FAA has written an issue paper on this outlining the risks and vulnerabilities in fault detection/ accommodation based on industry/agency experience over many years; and suggested means of compliance in terms of tests, analyses, simulations. The E-36 is requested to factor in the issue paper and build on the guidance content into an SAE document for reference by the industry. In this endeavor, it is recommended that the SAE standard/ARP consider conventional gas turbine controls as well as emerging architectures such Hybrid and Electric Propulsion Systems.

This test method describes a standardized process to evaluate the an aviation lubricant’s resistance to oxidation and corrosion-based degradation and to evaluate the fluid’s tendency to corrode various metals. Fluids are evaluated under a low-moisture atmosphere at a variety of times and temperatures.

The objective of this study was to examine the operating characteristics of a light duty multi cylinder compression ignition engine with regular gasoline fuel at low engine speed and load. The effects of fuel stratification by means of multiple injections as well as the sensitivity of auto-ignition and burn rate to intake pressure and temperature are presented. The measurements used in this study included gaseous emissions, filter smoke opacity and in-cylinder indicated information. It was found that stable, low emission operation was possible with raised intake manifold pressure and temperature, and that fuel stratification can lead to an increase in stability and a reduced reliance on increased temperature and pressure. It was also found that the auto-ignition delay sensitivity of gasoline to intake temperature and pressure was low within the operating window considered in this study.

An infrared laser absorption technique has been developed to measure in-cylinder concentrations of CO in an optical, automotive HCCI engine. The diagnostic employs a distributed-feedback, tunable diode laser selected to emit light at the R15 line of the first overtone of CO near 2.3 μm. The collimated laser beam makes multiple passes through the cylinder to increase its path length and its sampling volume. High-frequency modulation of the laser output (wavelength modulation spectroscopy) further enhances the signal-to-noise ratio and detection limits of CO. The diagnostic has been tested in the motored and fired engine, exhibiting better than 200-ppm sensitivity for 50-cycle ensemble-average values of CO concentration with 1-ms time resolution. Fired results demonstrate the ability of the diagnostic to quantify CO production during negative valve overlap (NVO) for a range of fueling conditions.

Amount and size distribution of wear particles in engine lubricating oil are indicators of the current machine condition. A change in size distribution, especially a rise in the amount of larger particles, often indicates a starting wear of some machine parts. Monitoring wear particles contained in lubricating oil during normal machine operation can help to identify the need for maintenance and more important to prevent sudden failure of the machine. An optical method is used to image a thin layer of oil to count and classify contained particles. Therefore, a continuous flow of undiluted oil from the oil circuit of the machine is pumped through the measurement instrument. Inside the instrument, the oil flow is directed through a thin transparent flow cell. Images are taken using a bright LED flashlight source, a magnification lens, and a digital camera. Algorithms have been developed to process and analyze the images.

Multiple-ribbed V belts have been widely used in automotive accessory drive systems to transmit power from crankshaft to power steering pump, alternator, and air conditioning (A/C) compressor. Overload under severe environmental conditions can lead to excessive slippage in the belt pulley interface in poorly designed accessory drive systems. This can lead to undesirable noise that increases warranty cost substantially. The mechanisms of this tribology phenomenon, noise features and system response are of utmost interest to the accessory drive system engineers. As accessory belt systems are usually used in ambient condition, the presence of water or moisture on belt is unavoidable under rainy or highly humid conditions. It has been found that the wet friction with negative coefficient of friction (cof)-velocity slope can lead to self-excited vibrations and squeal noise.

The European Union has defined legally binding CO2-fleet targets for new cars until 2030. Therefore, improvement of fuel economy and carbon dioxide emission reduction is becoming one of the most important issues for the car manufacturers. Today’s conventional car powertrain systems are reaching their technical limits and will not be able to meet future CO2 targets without further improvement in combustion efficiency, using low carbon fuels (LCF), and at least mild electrification. This paper demonstrates a highly efficient and performant combustion engine concept with a passive pre-chamber spark plug, operating at stoichiometric conditions and powered with liquefied petroleum gas (LPG). Even from fossil origin, LPG features many advantages such as low carbon/hydrogen ratio, low price and broad availability. In future, it can be produced from renewables and it is in liquid state under relatively low pressures, allowing the use of conventional injection and fuel supply components.

The present work investigates a means of controlling engine hydrocarbon startup and shutdown emissions in a Wankel engine which uses a novel rotor cooling method. Mechanically the engine employs a self-pressurizing air-cooled rotor system (SPARCS) configured to provide improved cooling versus a simple air-cooled rotor arrangement. The novelty of the SPARCS system is that it uses the fact that blowby past the sealing grid is inevitable in a Wankel engine as a means of increasing the density of the medium used for cooling the rotor. Unfortunately, the design also means that when the engine is shutdown, due to the overpressure within the engine core and the fact that fuel vapour and lubricating oil are to be found within it, unburned hydrocarbons can leak into the combustion chambers, and thence to the atmosphere via either or both of the intake and exhaust ports.

Air conditioning systems are one of the significant auxiliary loads on the vehicle powertrain. In an Electric Vehicle (EV) where the available energy is limited, it becomes crucial to optimize the overall energy consumption of the auxiliary loads. The major power consuming components in an automotive HVAC system (Heating, Ventilation and Air Conditioning) are: Compressor, Cabin blower, Condenser cooling fan and the Control devices. Significant progress is already made in enhancing the energy efficiency of the above-mentioned power consuming components part of vehicle HVAC system. Alternate energy sources are being explored recently, to reduce the energy demand from vehicle. One such proposal is to harness the abundant solar energy available, through solar panels and consume this energy to supplement the power required for HVAC system components. Solar panels convert solar energy to electrical energy by the principle of the photovoltaic effect.

During hot ambient, the cabin temperature of vehicle undergoing soaking may rise up to 70oC. Warm temperature and seats often turn uncomfortable to the passenger. The high temperature may result in thermal degradation of various plastic components, which in turn may release hazardous gases [2]. Usual practice to improve air quality inside the cabin includes switching on the air conditioning while keeping the window panes open. Such a practice minimizes the stabilization time to achieve comfortable cabin temperature. However, significant power requirement by the air-conditioning system during cool down cycle results in excess fuel consumption [7]. To eliminate these problems, the SOLAR POWERED INCABIN EVAPORATIVE COOLING SYSTEM can be installed in the car. This system uses a solar panel which converts the Solar energy into the Electrical energy. This energy can be used to recharge small battery or can be directly used to give necessary power for the cooling system.

The motivation of this work is to respond to high cabin temperatures within a parked/stationary vehicle which may cause discomfort and lead to vehicular heatstroke. The system also intends to ensure sufficient limits of oxygen within the vehicle cabin to prevent asphyxiation to the cabin occupants. The rise in global temperature is affecting the quality of air and comfort of occupants inside a parked car. There have been several cases reported of pets and children being left unattended or unsupervised in a parked car for a long period of time which have led to their deaths due to asphyxiation. The use of cost-effective materials like high density plastics for interior cabin trim have also been proven to contribute to cancer because of the emission of benzene a carcinogen by these plastics when exposed to extreme temperatures for long periods of time.

The present work discusses the developed simulation model aimed to predict the heat rejection (HR) performance and external pressure drop characteristics of automotive charge air cooler (CAC). Heat rejection and airside pressure drop characteristics of CAC were predicted for the conditions of different charge air mass flow rates and different cooling air velocities. The lack of detailed research on CAC performance prediction has motivated the development of the proposed simulation model. The present 1-D simulation has been developed based on the signal library of AMESIM application tool. Input parameters for this simulation such as core size, tube pitch, tube height, number of tubes, fin density, louver angle, louver pitch, charge air mass flow rate, cooling air velocity, charge air inlet temperature, and ambient temperature. Heat rejection curve and airside pressure drop of CAC were the output of the present simulation.

Radiators are types of heat exchangers, which are used to transfer the heat from one fluid to another fluid. It is mainly used in automobile engine cooling systems and the radiators are the major source of heat rejection from the system by cooling the working fluid (generally water or glycol mixture). The application of radiators in the two-wheeler vehicle segment plays a vital role in increasing engine efficiency by maintaining the optimum temperature inside the engine assembly. As the technology advances with higher power requirements for the two-wheeler vehicle segment, thermal management of combustion engine becomes a critical part of it, resulting in the advancement of radiator technology in terms of compactness and thermal performance. In order to cater to the increasing demand for high-powered engines, performance optimization of two-wheeler radiators becomes an important aspect of design.

This paper discusses the methodology setup for grill opening area prediction at the early development phase of the product development lifecycle, using a commercially available 1D simulation tool- AMESIM. Representative under hood has been modeled using Grill, Condenser, Radiator, intercooler, fan, and engine components. Vehicle velocity is used as an input to derive the airflow passing through the grill and other under-hood components based on ram air coefficient, pressure drop through different components (Grill, Heat exchanger, Fan & Engine). This airflow is used to predict the top tank temperature of the radiator. Derived airflow is correlated with airflow obtained from CFD simulation. A balance has been achieved between cooling drag & fan power consumption at different grill opening areas for target top tank temperature. Top tank temperature has been predicted at two different extreme engine heat rejection operating points.