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Abstract The stringent emission regulations for Internal Combustion Engines (ICEs) spawned a great amount of research in the field of innovative combustion approaches characterized by high efficiency and low emissions. Previous research demonstrate that such promising techniques, named Low-Temperature Combustion (LTC), combine the benefits of Compression Ignition (CI) engines, such as high compression ratio and unthrottled lean mixture, with low engine-out emissions using a properly premixed air-fuel mixture. Due to longer ignition delay and high volatility compared to diesel, gasoline-like fuels show good potential for the generation of a highly premixed charge, which is needed to reach LTC characteristics. In this scenario, gasoline Partially Premixed Combustion (PPC), characterized by the high-pressure direct injection of gasoline, showed good potential for the simultaneous reduction of pollutants and emissions in CI engines.

This document deals with ground and flight test of airplane installed Environmental Control Systems (ECS), Figure 1. The ECS provide an environment, controlled within specified operational limits of comfort and safety, for humans, animals, and equipment. These limits include the following: pressure, temperature, humidity, ventilation air velocity, ventilation rate, wall temperature, audible noise, vibration, and environment composition (ozone, contaminants, etc.). The ECS are composed of equipment, controls, and indicators that supply, distribute, recycle and exhaust air to maintain the desired environment.

Mack Trucks begins production of LR Electric

The sounds produced by noise sources, such as engine, tire-road interaction, wind noise, and engine auxiliaries, and transmitted through the air to the cabin are called airborne noise. The acoustic package of the vehicle is designed to provide the desired sound comfort in the passenger cabin following the vehicle target. Here, the acoustic pack of the vehicle act as a barrier in front of the sound wave, reducing its energy by reflecting it toward the source (insulation) or by transforming the sound energy to heat energy (absorption). The pressure on reducing CO2 emission in Internal Combustion Engines (ICEs) and the requirements to increase range in electric vehicles (EV) always tend to the reduction of vehicle weight.

With the need for a compact system of transportation, the auto-rickshaw has evolved over the years, and since then auto-rickshaws have proven to be an important means of public transport. Lately, auto-rickshaws have been contributing enormously to air pollution. Due to this, people are preferring alternative means of transportation, and electrification is one of them. Electrification of auto-rickshaws results in a low-cost and environment-friendly source of transportation in urban cities where pollution rates are alarmingly high. The efficiency of electric auto-rickshaws plays a significant role because it has to compete with the present internal combustion (IC) engine auto-rickshaws and should have a higher priority to be chosen as the public’s option of transport. The primary aim of this project is to optimize the electric powertrain for auto-rickshaws by minimizing the consumption of energy.

Driver drowsiness is a major cause of vehicle accidents, and facial images are highly valuable to detect drowsiness. In this paper, we perform our research via a thermal camera to record the driver’s facial images on a driving simulator. A robust real-time algorithm extracts the features using horizontal and vertical integration projection, contours, contour orientations, and cropping tools. The features are included four target areas on the cheeks and forehead. Qt compiler and OpenCV are used with two cameras with different resolutions. A high-resolution thermal camera is used for fifteen subjects, and a low-resolution one is used for a person. The results are investigated by four temperature plots and evaluated by Observer Rating of Drowsiness.

This paper introduces a novel personal rapid transit (PRT) system and further describes the process of designing and optimizing the suspension system for the prototype vehicle. The objective of the prototype development is to build a small, low-cost, lightweight, and comfortable vehicle. The current build of the vehicle lacks enough roll stiffness or a smooth ride. As such, a complete redesign of the suspension system for the next generation of prototypes is desired. The Short-Long Arm (SLA) double wishbone suspension with an outboard coil is the design of choice for the new prototype. To evaluate the ride and safety, a quarter-car model is evaluated for suspension travel, body acceleration, and dynamic wheel load over a pseudo-random road profile. The results from these models show a comparison between the two prototype vehicles in relation to their ride comfort and safety.

Abstract Emission Control has always been a major concern in each and every field. An increase in emissions leads to climate change, global warming, and even various diseases. The transportation system is responsible for around 30% of emission production, of which 70% of the total atmospheric burden comes from automobiles. Recently developed emission-free electric vehicles have positively affected the levels of impurity in the environment, yet the remaining Internal Combustion Engine (ICE) vehicles on the road have been left with unchecked emissions. Traditional Catalytic Converters are widely used to reduce the emissions of vehicles. It works on the principle of converting hazardous gases emitted from the engine to less harmful carbon dioxide (CO2), nitrogen (N2), and water (H2O). It is integrated with the exhaust of the engine. High efficiency and better emission control catalytic converters are still major milestones to achieve for automotive industries.

This SAE Recommended Practice provides test protocols with performance requirements for camera monitor systems (CMSs) to replace existing statutorily required inside and outside rear-view mirrors for U.S. market road vehicles. This practice expands specific technical content while retaining harmonization with the FMVSS 111 rear visibility standard and other international standards. This is accomplished by defining required roadway fields of view as specific fields of view (FOV) displayed inside the vehicle. Specific testing protocols and/or specifications are added to enhance ease of use using straightforward language, and any specifications are intended to be independent of different camera and display technologies unless otherwise explicitly stated.

Abstract This research develops a hierarchical control strategy to improve the stability of multi-axle electric vehicles with in-wheel motors while driving at high speed or on low adhesion-coefficient roads. The yaw rate and sideslip angle are chosen as the control parameters, and the direct yaw-moment control (DYC) method is employed to ensure the yaw stability of the vehicle. On the basis of this methodology, a hierarchical yaw stability control architecture that consists of a state reference layer, a desired moment calculation layer, a longitudinal force calculation layer, and a torque distribution layer is proposed. The ideal vehicle steering state is deduced by the state reference layer according to a linear two-degree-of-freedom (2-DOF) vehicle dynamics model.

Abstract Fretting failure mode is commonly observed at the contact interface of mating parts, held together under normal load and subjected to vibratory and/or imbalanced system forces. This article presents the fretting fatigue life estimation of a complete flat-flat contact pair using a relatively new approach, i.e., deviatoric strain amplitude-based (SI) parameter, further combined with Ding’s empirical parameter D fret2, which considers the effect of resultant frictional work on fretting fatigue life. The results are compared with traditional critical plane-based methods like Smith-Watson-Topper (SWT) and Fatemi-Socie (FS). Observing high load-factor values corresponding to material yielding, non-linear material models are considered to account for possible plastic shakedown/ratcheting phenomenon. Overall good experimental correlation is observed for all three fatigue initiation methods, within a ±3N scatter band.

Abstract Considering the biodiesel composition, blend percentage, and temperature as input variables in the models to predict biodiesel-diesel blends’ properties is imperative. However, there are no models available in the literature to predict the properties of biodiesel-diesel blends that consider all these variables. The accuracy of spray and combustion models for diesel engines depends on the accuracy at which the fuel properties are estimated. Thus, straightforward approaches to accurately predict the properties of biodiesel-diesel blends are required. A novel reference property-based approach is proposed in the present work to predict the biodiesel-diesel blends’ properties to address this research gap. Models available in the literature correlating the properties of interest to fuel temperature were modified by including a reference property measured at 293 K.

Abstract Compressed natural gas (CNG) is a promising alternative fuel for compression ignition (CI) engines under dual-fuel (DF) mode operation. Its application on commercial heavy-duty multicylinder diesel engines is scarcely reported, and its potential usage is investigated through a research study. The focus of this research was to study the in-cylinder combustion and its effect on emissions with an increasing energy fraction of CNG at different speeds (1000 rpm-2500 rpm) and load conditions (Speed-Torque mode), inducted through the intake manifold at different mass flow rates ranging from 0.67 kg/h to 4.0 kg/h corresponding to an energy substitution rate (ESR) of 1.9%-60.2% while using diesel as pilot fuel. In-cylinder pressure, heat release rate (HRR), and pressure rise rate (PRR) increased with the increase in CNG mass flow rate (CMFR). Combustion duration is prolonged under diesel-CNG DF (DDF) mode while ignition delay (ID) is reduced with an increase in CNG flow rate.

Abstract Numerical simulation represents a fundamental tool to support the development process of new propulsion systems. In the field of large-bore dual-fuel (DF) engines, the engine simulation by means of fast running numerical models is nowadays essential to reduce the huge effort for testing activities and speed up the development of more efficient and low-emissions propulsion systems. However, the simulation of the DF combustion by means of a zero-dimensional/one-dimensional (0D/1D) approach is particularly challenging due to the combustion process evolution from spray autoignition to turbulent flame propagation and the complex interaction between the two fuels. In this regard, in this activity a 0D/1D multi-zone DF combustion model was developed for the simulation of the combustion process in large-bore DF engines.

Abstract High-speed flame imaging has been widely used to investigate flame propagation in optically accessible direct-injection spark-ignition (DISI) engines. Previous studies utilized a high-speed movie to measure the overall growth rate of the flame and to analyze the flame shape and its correspondence with engine performance and efficiency. This study proposes the flame image velocimetry (FIV), a new diagnostic method enabling time-resolved, two-dimensional flame front vector extraction and turbulence intensity calculation. The high-speed camera is used to record the propagating petrol flame, and contrast variations are tracked to derive flow vectors. The PIVlab, a Matlab-based open-source code, is used for this flame front FIV analysis, and the systematic optimization of processing parameters is performed. The raw flame images are preprocessed using the contrast-limited adaptive histogram equalization (CLAHE) filter before a four-step fast Fourier transform (FFT) is applied.

With over thirty years of experience in the design, development, and patenting of some products in the field of wheel alignment, the author shares his knowledge on the importance of wheel maintenance to the overall performance of a vehicle. From the ancient bullock carts to chariots to automobiles, wheels have undergone many changes to serve the purpose of mankind's mobility. Mobility is inevitable in today's life. A world without wheels is unimaginable. Every vehicle owner expects his tires to last longer and perform better. But improper wheel alignment and wheel balancing can drastically impact the wear and tear on a tire. This book walks the readers through the basics to techniques for wheel alignment on light vehicles, commercial vehicles, and trailers. In addition, illustrations present various types of tire wear and the cause of each. Finally, the author delves into tire safety from understanding how air pressure effects a tire to the importance of tire rotation.

This specification covers the requirements for thin, hard, dense electrodeposited chromium plating on surfaces of ferrous and nonferrous alloys.