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The main objectives this paper is two-fold. First, the paper highlights the role of good road and traffic infrastructure for improving the on-road fuel economy of vehicle. Second, it investigate the dynamic driving parameters like positive tractive power level, modes of driving and velocity acceleration envelopes, affecting the on road energy demand and fuel economy. In this study, the gasoline passenger car was driven about 260 km each on two different intercity highways by same driver and at same load. The road and traffic condition of two highways was chosen entirely different, one highway as well organized and other as poorly organized. The fuel consumption and speed time trace were captured using on-board equipments in the field run. The average on road fuel economy was observed as 16.65 km/l (around 18% higher) for well organized highway as compared to 14.13 km/l for other highway.

Recently, several bus systems whose routes are determined by passenger demands transmitted from bus stops have proven to be failures. The paper records efforts to compare the efficiency and degree of success of the various systems. The paper describes the organization of one such system ("Cosby"). The heart of the system is a computer which continually updates bus routes according to passenger demands; these route changes are then transmitted to the bus drivers. The advantages of this system are compared to those of conventional bus systems; in general, the demand-controlled buses can respond to varying amounts of passengers more economically, while conventional buses operate most efficiently with high passenger traffic. This conclusion leads to a description of combinations of demand-controlled and conventional buses. A subsequent simulation of bus lines has demonstrated the potential advantages of such a system.

The characteristics of suspension elastic elements (i.e., spring, damper and anti-roll bar) are directly related to the handling and ride comfort performances, how to tune the characteristics of suspensions' elastic elements is always a big issue in developing the chassis of a vehicle. In this paper, a multi-body dynamics model of a passenger car within MSC.ADAMS® is integrated with iSight FD®, an optimization tool, to carry out a multi-objective optimization for improving the behavior of vehicle handling and ride comfort. The characteristics of suspension elastic elements (i.e., spring, damper and anti-roll bar) are considered as design variables. For handling, the objectives are defined by the measurements from multi-body dynamics simulation of typical double lane change according to ISO3888 standard. For ride comfort, the frequency-weighted RMS (Root Mean Square) value of vertical acceleration of the front seat rail according to ISO2631 standard is set as the objective.

The purpose of this investigation on vehicle side-impact stiffness and the comparison of the static and dynamic tests was to contribute guidelines for a final test procedure with two advantages: to be, on the one hand, simply practicable and reproducible and, on the other hand, to provide results corresponding as close as possible to real accidents. Additionally, the investigation emphasized testing of side parts significant to the objectives of the test: door only, door and sill, or door, sill and roof. New cars as well as heavily rusted vehicles were used for the test. Therefore this paper also treats the question of what degree a test of only new cars will be useful, without considering the state of corrosion of older vehicles.

The EcoCAR3 competition challenges student teams to redesign a 2016 Chevrolet Camaro to reduce environmental impacts and increase energy efficiency while maintaining performance and safety that consumers expect from a Camaro. Energy management of the new hybrid powertrain is an integral component of the overall efficiency of the car and is a prime focus of Colorado State University’s (CSU) Vehicle Innovation Team. Previous research has shown that error-less predictions about future driving characteristics can be used to more efficiently manage hybrid powertrains. In this study, a novel, real-world implementable energy management strategy is investigated for use in the EcoCAR3 Hybrid Camaro. This strategy uses a Nonlinear Autoregressive Artificial Neural Network with Exogenous inputs (NARX Artificial Neural Network) trained with real-world driving data from a selected drive cycle to predict future vehicle speeds along that drive cycle.

Vehicular Network is an emerging and developing technology to improve traffic management and safety issues, and enable a wide range of value-added services such as collision warning/avoidance. Many applications have been designed to provide safety and comfort for passengers. This technology is a prolific area for attackers who will attempt to challenge the network with their malicious or rational attacks. In this paper we elaborate what a vehicular network is, different kinds of communication in this field, main mechanism and related parts and how vehicular networks work then we introduce some of its applications. After primary familiarity with this system we investigate to different type of attacker, more important security issues, How to secure vehicular networks (security requirements and some tools and methods to achieve secure vehicular networks), difficulties and providing viable security solutions, and at the end briefly explanation of related standards.

In this paper a methodology is presented to predict the water drop trajectories at a given fan operating condition (i.e., face velocity), coil height and for a range of water drop diameters. Water drop carry over horizontal distances have been calculated as a function of evaporator coil height, water drop diameters, and face velocities for an evaporator unit. The simulated data has been compared with the experimental data. Initial results have shown that the model can predict the water drop trajectories fairly well. The developed model can be used to calculate the maximum horizontal distances the water drops will be carried over with the airstream for a range of water drop diameters. This is very important information to the design engineers for properly designing the evaporator units.

Icing related problems on aero-components have been recognized since the beginning of modern aviation. Various icing incidents occurred due to severe degradation of aerodynamic performance, and engine rollbacks. As in-flight icing can occur over a broad range of atmospheric and flight conditions, design of effective ice protection mechanisms on aero-components is essential. Computational simulations are a significant part of designing these mechanisms, therefore accurate prediction of droplet collection efficiency and accreted ice shapes are vital. In the current study, continued efforts to improve a computational in-flight icing prediction tool are introduced together with obtained results. The emphasis in this study is on the recent improvements introduced to flow-field and droplet trajectory calculation modules. The flow-field predictions were previously managed by Hess-Smith panel method and this module is fortified with inclusion of an open-source Navier-Stokes code.

This paper presents simulation and experimental results of the effects of intake water injection on the main combustion parameters of a turbo-charged, direct injection spark ignition engine. Water injection is more and more considered as a viable technology to further increase specific output power of modern spark ignition engines, enabling extreme downsizing concepts and the associated efficiency increase benefits. The paper initially presents the main results of a one-dimensional simulation analysis carried out to highlight the key parameters (injection position, water-to-fuel ratio and water temperature) and their effects on combustion (in-cylinder and exhaust temperature reduction and knock tendency suppression). The main results of such study have then been used to design and conduct preliminary experimental tests on a prototype direct-injection, turbocharged spark ignition engine, modified to incorporate a new multi-point water injection system in the intake runners.

Predicting Exterior Water Management is important for developing vehicles that meet customer expectations in adverse weather. Fluid film methods, with Lagrangian tracking, can provide spray and surface water simulations for complex vehicle geometries in on-road conditions. To cope with this complexity and provide practical engineering simulations, such methods rely on empirical sub-models to predict phenomena such as the film stripping from the surface. Experimental data to develop and validate such models is difficult to obtain therefore here a high-fidelity Coupled Level-set Volume of Fluid (CLSVOF) simulation is carried out. CLSVOF resolves the interface of the liquid in three dimensions; allowing direct simulation of film behaviour and interaction with the surrounding air. This is used to simulate a simplified wing-mirror, with air flow, on which water is introduced.

The material demands for advanced technologies have led to development of new generation, light-weight, and multi-functional materials. Aluminum matrix composites (AMCs) have captured considerable attention in aviation, space and automotive industries in recent years. Carbon nanotubes (CNT) are one of the most promising candidate of reinforcements used to improve mechanical strength and hardness of metal matrix composites (MMCs). In this study, dry sliding wear behavior of aluminum (Al) matrix (MMCs) reinforced with different amounts (0, 0.5, 1 and 2 wt%) of CNTs were prepared through ball milling, the process was followed by compaction at room temperature and pressureless sintering at 630 °C under argon atmosphere for 1hr. Wear tests were performed on a pin-on-disk tribometer against SAE 1040 steel counter body under constant load and sliding speed at room temperature.

The aim of this work was to investigate the wear mechanisms occurring in passenger car diesel engine inlet valves and seat inserts using a bench test-rig designed to simulate the loading environment and contact conditions to which the valve and seat are subjected. The investigation has shown that the valve and seat insert wear problem involves two distinct mechanisms: impact of the valve on the seat insert on valve closing and sliding of the valve on the seat insert under the action of the combustion pressure. The prevailing wear mechanisms have been shown to be related to critical operating conditions such as valve closing velocity, combustion load and valve misalignment relative to the seat insert and valve and seat insert material choice.

The wide applications of aluminum composites in the defense, automotive and aerospace industries interest researchers in developing hybrid nanocomposites with specific properties such as high strength, hardness, and wear resistance. The aluminum was reinforced by silicon carbide (SiC) nanoparticles with a constant weight composition, and the spark plasma sintering process fabricated zirconium dioxide (ZrO2) nanoparticles with a different weight composition. The hybrid composite material’s density, porosity, and hardness were assessed using the SEM images of composites and hybrid nanocomposites that were effectively created by the sintering process without particle agglomeration. A pin-on-disc device was used for the wear test, with different input parameters such as weight (20, 25, 30, and 35 N), varying sliding distance (300, 500, 700 and 900m) and diverse sliding speeds (1, 1.5, 2 and 2.5 m/sec).

This research is an attempt to investigate the possibility of enhancing wear and corrosion behaviour of aluminium alloy and composites for high-temperature applications. The 319 alloys with minor additions of Ni, Ti and Fe elements using the liquid metallurgy technique, Al-Si-Cu-Mg matrix alloy (Al alloy) was obtained and it was used as a base alloy and it is reinforced with Silicon carbide (SiC), Magnesium oxide (MgO) under the following composites, namely Al alloy/3wt % MgO (AA-SRM), Al alloy/ 3wt % SiC (AA-SRS) and Al alloy/3wt %SiC-3wt % MgO (AAHRSM) using a stir casting route. The wear test was investigated under the following factors, namely constant sliding velocity 3.21 m/s, sliding distance up to 10000 m under different loadings (4.9, 9.8, 14.7, 19.62, and 24.5 N) using wear test by a pin on the disc test rig. The wear rate was calculated using the tested samples under different loadings, sliding distance, and weight concentration conditions.

This paper is first in a series of papers designed to investigate wear processes in modern heavy duty diesel engines. The objective of the series is to discuss the effects that engine drive cycle, lubricant formulations and in-service ageing of lubricants have on wear of critical engine components. In this paper, the Radioactive Tracer Technology technique was used to study the steady state wear behavior of a number of contacting surfaces in a Caterpillar 1P engine, as a function of the drive cycle. A test protocol consisting of 7 modes or stages was used to simulate a variety of drive cycles. The results from this work provide useful insights into the wear behavior of these surfaces under a variety of speed and load conditions.

While laser-welded preforms provide significant advantages in sheet metal stamping, similar technology has not been developed for forging. In the present paper, the case for solid-state welded preforms in forging is considered and the workability and mechanical properties of selected base metal combinations are analyzed. Results demonstrate that welded preforms have adequate workability based on upsetting and side pressing tests though flow tends to be non-uniform in bi-metal preforms. Tensile tests indicate that the mechanical properties of side pressed preforms are equivalent to those of annealed base metal pieces. While work is ongoing to develop their use, results indicate that friction-welded preforms have potential for use in forging.

There are a number of numerical and experimental studies of the aerodynamic performance of wheels that have been published. They show that wheels and wheel-housing flows are responsible for a substantial part of the total aerodynamic drag on passenger vehicles. Previous investigations have also shown that aerodynamic resistance moment acting on rotating wheels, sometimes referred to as ventilation resistance or ventilation torque is a significant contributor to the total aerodynamic resistance of the vehicle; therefore it should not be neglected when designing the wheel-housing area. This work presents a numerical study of the wheel ventilation resistance moment and factors that affect it, using computational fluid dynamics (CFD). It is demonstrated how pressure and shear forces acting on different rotating parts of the wheel affect the ventilation torque. It is also shown how a simple change of rim design can lead to a significant decrease in power consumption of the vehicle.

Passenger car fuel consumption is a constant concern for automotive companies and the contribution to fuel consumption from aerodynamics is well known. Several studies have been published on the aerodynamics of wheels. One area of wheel aerodynamics discussed in some of these earlier works is the so-called ventilation resistance. This study investigates ventilation resistance on a number of 17 inch rims, in the Volvo Cars Aerodynamic Wind Tunnel. The ventilation resistance was measured using a custom-built suspension with a tractive force measurement system installed in the Wheel Drive Units (WDUs). The study aims at identifying wheel design factors that have significant effect on the ventilation resistance for the investigated wheel size. The results show that it was possible to measure similar power requirements to rotate the wheels as was found in previous works.

In this paper, an electronically controlled hydraulic semiactive system for the seat suspension of wheeled tractors is theoretically designed to improve the driver ride comfort. Using a three degrees of freedom mathematical model, the damping force controller is designed based on optimal control theory and Nelder / Mead Simplex minimization method to perform a limited state feedback information. The controller considers the damping constraint which adapts the actual damping between the prescribed limits. The model results are generated when excited by a statistically random road profile. The results are presented in time and frequency domains. The driver vertical acceleration for semi-active and conventional passive systems are compared at similar root mean square (r.m.s) value of suspension working space. The semiactive system achieved a significant improvement, 18 percent, over the passive system with no power requirement from the tractor engine.

Whiplash injuries due to automotive collisions have occupied a major portion of the insurance claims in Korea and other nations. In this study, a survey of head restraint use in the field was performed by measuring the positions of head restraints in 1,100 passenger vehicles in the downtown and outskirts areas of Seoul. Using an international protocol published by the Research Council for Automobile Repairs (RCAR), 19% of the measured head restraint positions were evaluated as “good” and 36% were evaluated as “poor”. This result differentiates a recent report of the improvement in design of head restraints geometry and reveals that motorists are not appropriately utilizing head restraints. Statistical analysis of the survey results revealed valid correlations between the measurements and subjective questions. Simulations with various parameters such as impact speed, direction and head restraint positions were also performed utilizing an FE human model.