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Acoustic Impact of Electric Vehicles
Abstract
Electric vehicles (EV) diffusion depends on many
factors among which policies, people options, and economic
factors. Their noise-related performance could appear
favourable. This notwithstanding, despite partisan opinions, the
analyses carried out suggest that research and industry will have
to minimise the collateral issues posed by a quite probable EV
diffusion. The objective of the study presented in this paper is to
analyse the acoustic impact of electric vehicles (EV) and to set
up an overall framework for an effective management of their
diffusion. After the objectives, EV overall characteristics are
analysed. EV acoustic performance are then analysed. In the
final discussion, the main characteristics of the required holistic
approach are highlighted. This can benefit both researchers and
practitioners.
... The outcomes of the main initiatives are summarized in Table II: they range from proposals of sounds for EVs, to approaches aimed at minimising the noise pollution while preserving safety of pedestrians, to the design of a car acoustic identity looking at both interior and exterior sounds and their effects on user-vehicle interaction. Additional references to research projects dealing with EVs sound are available in [25]. ...
... Comune di Firenze, Continental, iPOOL, Université Gustave Eiffel, Università degli Studi Mediterranea di Reggio Calabria, Vie en.ro.se Ingegneria -Project Life E-VIA [25] In the framework of vehicle sounds and related issues, the E-VIA project has several aims: to tackle acoustic pollution from road traffic noise, assuming that in the future EHV's will contribute the most part of traffic flow; to support combined optimization of road and tyre design, to come up with a solution able to reduce noise in urban areas and life-cycle costs. Additionally, researchers involved in the project aim to support the effective adoption of the EU regulation, by providing rolling noise coefficients determined by using the Common Noise Assessment Method (CNOSSOS-EU) specifically tuned for EVs. ...
... The current trend to emobility further contributes to the importance of acoustic design. Noise arising from auxiliary aggregates can become unpleasant due to the absence of combustion engine noise [5][6][7][8][9]. Ideally, acoustic aspects are already considered during the design phase by means of CAA. ...
The hybrid aeroacoustic approach is an efficient way to address the issue of the disparity of scales in Computational AeroAcoustics (CAA) at low Mach numbers. In the present paper, three wave equations governing propagation of flow-induced sound of low Mach number flows, namely the Perturbed Convective Wave Equation (PCWE), Ribner’s Dilatation (RIB) equation, and Lighthill’s wave equation, are applied using the Finite Element Method (FEM). An airflow through a circular pipe with a half-moon-shaped orifice at three operating flow speeds is considered, where validation data from measurements on a dedicated test rig is available. An extensive analysis of the flow field is provided based on the results of the incompressible flow simulation. The resulting acoustic source terms are investigated, and the relevant source term contributions are determined. The results of the acoustic propagation simulations revealed that the PCWE and RIB are best suited for the present task. The overall deviation of the predicted pressure spectra from the measured mean values amounted to 2.26 and 2.13 times the standard deviation of the measurement compared to 3.55 for Lighthill’s wave equation. Besides reliably predicting the flow-induced sound, the numerical procedure of source term computation is straightforward for PCWE and RIB, where the source term contributions, shown to be relevant, solely consist of time derivatives of the incompressible pressure. In contrast, the Lighthill source term involves spatial derivatives and, thus, is strongly dependent on the spatial resolution and the numerical method actually used for approximating these terms.
... Tire-road noise for EVs is the main topic of the ongoing LIFE project "E-VIA" (2019-2023) [19][20][21][22][23][24]. In more detail, the E-VIA project aims at 1) Considering the contribution (i.e., both the noise and air pollution mitigation efficiency) of EVs and hybrid vehicles with respect to the current scenarios. ...
Electric vehicles (EVs) are progressively entering into the current noisy urban ecosystem. Even though EVs are apparently quieter than traditional Internal Combustion Engine Vehicles (ICEVs), they have an impact on noise maps and road pavement designers should take this into consideration when designing future low-noise road pavements. Consequently, the main objective of this study is to define what are the most important aspects that road pavement designers should take into account. For this reason, in this paper, the noise emitted by EVs was analysed, considering parameters ( e.g. , speed and frequency) and comparisons, in order to identify crucial characteristics. Results show that EV noise could call for the improvement of pavement acoustic design due to the Acoustic Vehicle Alerting System (AVAS), high-frequency peaks, and noise vibration harshness.
... The framework of the study carried out to optimize the low-noise asphalt concrete mixtures, which are the main outputs of the LIFE E-VIA Project, are described in the following. In particular, the study consisted of 3 main tasks (see Figure 1) that were organized as follows: TASK 1.1: A comprehensive literature analysis [9][10][11], which allowed finding 150 asphalt concrete mixtures, was carried out (Actor: University MEDITERRANEA of Reggio Calabria, UNIRC; Project Action: A2). TASK 1.2: From the 150 asphalt concrete mixtures above, nine mixtures were selected based on many characteristics, including: 1) Acoustic response. ...
The paper deals with the acoustical characterization of low-noise asphalt concretes developed for noise reduction in urban areas within the LIFE E-VIA project (LIFE18 ENV/IT/000201). With the perspective of an increasing number of electric vehicles (EVs) in urban area, the asphalt concrete mixes have been optimized considering Life Cycle Cost with respect to actual best practices. Two very thin asphalt concretes (VTAC) of 6 mm maximum aggregate size have been implemented on a reference test track in France. Both are based on the same formulation, but one mix contains 1.9% crumb rubber by weight. The noise performance of these prototype test sections has been evaluated by means of close-proximity (CPX) tests and controlled pass-by (CPB) noise measurements for two EV models. CPX results have shown a noise reduction of about 3 dB(A) by comparison with a reference dense asphalt concrete 0/10, while an average pass-by noise reduction of about 4 dB(A) has been observed for the sample of EVs tested.
... In highly populated areas, where overexposure is observed, the main source of environmental noise is vehicular traffic [6][7][8], and the relationship between environmental noise and specific health effects least 5 dBA compared to traditional pavements and 2 dBA compared to the other traditional porous asphalt pavements, using more sustainable low-noise surfaces composed by recycled asphalt pavements and crumb rubber from scrap tires mixed with binders at warm temperatures. Finally, the LIFE project E-VIA [34,35], which is based on data from the World Health Organization (WHO) and the European Environment Agency (EEA), aims at reducing the future noise pollution from road traffic noise for electric vehicles (EVs): (1) considering the contribution of EVs and hybrid vehicles with respect to the current scenarios; (2) optimizing both road pavements and tires (durability and sustainability for EVs (which, in turn, reduce the life cycle cost with respect to actual best practices); (3) contributing to EU legislation effective implementation (EU Directives 2002/49/EC, and 2015/996/EC, and CNOSSOS-EU); (4) raising people's awareness of noise pollution and health effects. Finally, it is important to mention bituminous mixtures containing expanded clay. ...
The sound absorption of a road pavement depends not only on geometric and volumetric factors but also on pore shape factors. In turn, pore shape factors mainly refer to thermal and viscous factors (i.e., thermal and viscous effects that usually occur inside porous materials). Despite the presence of a number of studies and researches, there is a lack of information about how to predict or estimate pore shape factors. This greatly affects mixture design, where a physical-based or correlation-based link between volumetrics and acoustics is vital and plays an important role also during quality assurance and quality control (QA/QC) procedures. Based on the above, the objective of this study is to link mixture volumetrics and pore shape factors. In particular, 10 samples of a porous asphalt concrete were tested in order to estimate their thickness, air voids content (vacuum-sealing method, ASTM D6857/D6857M), sound absorption coefficient (Kundt’s tube, ISO 10354-2), airflow resistivity (ISO 9053-2), and permeability (ASTM PS 129). Subsequently, two models (herein called STIN and JCAL) were used to derive both volumetrics and pore shape factors from the estimated parameters listed above, and statistical analysis was carried out to define correlations among the parameters and models performance. Results confirm the complexity of the tasks and point out that estimates of the pore shape factors can be derived based on mixture volumetrics. Results can benefit researchers (in acoustic and pavement mixtures) and practitioners involved in mix design and pavement acceptance processes.
Despite almost a century of studies dealing with traffic noise, researchers and practitioners still face old and new issues when designing a low-noise pavement. Given that, this manuscript aims at focusing on a number of unsolved questions, namely theoretical or technological. 1) Is it viable to balance diverse road-related needs (i.e., noise, expected life, texture levels, and friction)? 2) How much does the pavement material affect its acoustic performance (the remaining factors being constant)? 3) How much reliable is the relationship between road texture, and mixture aggregate gradation? Based on the analysis of these issues, it emerges that: 1) optimal pavement design involves complex mix optimization and there are theoretical and practical bases to set up a balanced approach to address the complexity of pavement design; 2) high percentages of crumb rubber could optimise road acoustic response but this latter has a relationship with the tyre/road noise (expressed, for example, in terms of close proximity index) that calls for further investigation; 3) aggregate gradation appears to be a reliable basis to predict surface texture and therefore, under given boundary conditions, tyre/road noise; and 4) further studies and investigations are needed in terms of local calibration of deterioration curves and setting up of a sound method to assess the frequency response of asphalt concretes and to govern on-site noise indicators based on mixture properties.
The CO2 legislation has become more restrictive over time, and to reach the goals imposed by this legislation the automotive industry saw in the hybrid vehicles a solution. Technologies like micro, mild, full and plug in hybrids emerged in order to achieve the imposed goals. This article will provide an overview of the status of micro and mild hybrid technology and is intended to show that this type of technologies is a necessary step until the barriers are not exceeded and purely electric vehicles become the mainstream.
Electric vehicles are considered as an important means to cope with increasing environmental problems in the transport sector. Many governments worldwide have set targets to increase the number of electric vehicles, although their environmental benignity is not ensured in the scope of the policies implemented. The core objective of this paper is to investigate the overall environmental impact of electric vehicles in different regions. The analysis is based on a life cycle assessment of electric vehicles including emissions from electricity generation, vehicle production and disposal, and vehicle use. The major conclusion is that the environmental benignity of electric vehicles is very sensitive on: electricity mix (a); number of km driven per year (b) and embedded emissions in car production (c), as well as battery recycling. Yet, as shown in this paper the highest sensitivity is with respect to the electricity mix. Hence, to make electric vehicles more environmentally friendly it is most important to increase the share of renewable energy sources in electricity generation.
Electric vehicles (EV) are the immediate solution to drastically reducing pollutant emissions from the transport sector. There is a continuing increase in the number of EVs in use, but their widespread and massive acceptance by automotive consumers is related to the performance they can deliver. The most important feature here (a hot topic at present in EV research) is related to the possibility of providing a more accurate prediction of range. Range prediction is a complex problem because it depends on a lot of influence factors (internal, external, constant, variables) and the present paper aims to investigate the effect of these factors on the range of EVs. The results and aspects of current worldwide research on this theme are presented through the analysis of the main classes of influence factors: Vehicle design, the driver and the environment. Further, the weight and effect of each potential factor which influences EV range was analyzed by presenting current issues. An exhaustive and comprehensive analysis has made it possible to identify future research and development directions in the EV research field, resulting in massive future and immediate EV penetration in the automotive market.
Sustainable transportation is an essential part of a sustainable city; however, modern transportation systems with internal-combustion engines emits unacceptably high level of air-pollutants and noise. It is recognized widely that road-traffic noise has negative health impacts (such as annoyance and sleep disturbance) on exposed population in highly-populated cities. These harmful effects should be removed or at least reduced to guarantee the sustainability of modern cities. The estimation of pollutant levels at a specific location and the extent of the damage is therefore important for policy makers. This study presents a procedure to determine the levels of road-traffic noise at both day and night, and an assessment of the adverse health effects across Gwangju Metropolitan City (GMC), Republic of Korea (ROK). Road-traffic noise maps in 2-D and 3-D were generated, in order to find spatial distribution of noise levels across the city and noise level at the façade of a building-floor, respectively. The adoption of existing assessment models for the highly-annoyed (%HA) and highly-sleep-disturbed (%HSD) leads to building-based estimation of the affected population and spatial distribution of the road networks of the city. Very high noise levels were found to exist along major roads in the day and at night, with little difference between them. As a result, approximately 10% and 5% of the total population (n = 1,471,944) were estimated to experience high-level annoyance and sleep disturbance, respectively.
Introduction of electric vehicles (EVs) signal the beginning of the end for traditional engine vehicles. The major motivators for shifting to EVs are the need for reducing polluting engine emissions and reducing dependence on costly oil fuels. By the end of 2016, the global stock of EVs crossed the two million mark. The growing acceptance of EVs is the outcome of several factors: technological advancements, rising storage capacity of traction batteries coupled with their falling cost, increased public charging facilities and Govt. incentives. The two EV technologies currently remain at the top are the battery electric vehicles (BEVs) and plug-in hybrid electric vehicles (PHEV). This paper gives an overview of various EV technologies, their features, limitations and challenges in their bulk deployment as a replacement to conventional vehicles.
Electric vehicles reduce pollution only if a high percentage of the electricity mix comes from renewable sources and if the battery manufacturing takes place at a site far from the vehicle use region. Industries developed due to increased electric vehicle adoption may also cause additional air pollution. The Indian government has committed to solving New Delhi's air pollution issues through an ambitious policy of switching 100% of the light duty consumer vehicles to electric vehicles by 2030. This policy is based on vehicle grid interaction and relies on shared mobility through the electric vehicle fleet. There are several human behavioral changes necessary to achieve 100% adoption of electric vehicles. This paper reviews different steps in the lifecycle of an electric vehicle (EV), their impact on environmental emissions, and recommends policies suitable for different socio-economic group that are relevant to the Indian market. To reduce air pollution through adoption of electric vehicles, the Indian government needs to adopt policies that increase sale of electric vehicles, increase percentage of renewable energy in the electricity mix, and prevent air pollution caused from battery manufacturing. The recommended policies can be customized for any market globally for reducing air pollution through increased adoption of electric vehicles.
An important barrier to electric vehicle (EV) sales is their high purchase price compared to internal combustion engine (ICE) vehicles. We conducted total cost of ownership (TCO) calculations to study how costs and sales of EVs relate to each other and to examine the role of fiscal incentives in reducing TCO and increasing EV sales. We composed EV-ICE vehicle pairs that allowed cross-segment and cross-country comparison in eight European countries. Actual car prices were used to calculate the incentives for each model in each country. We found a negative TCO-sales relationship that differs across car segments. Compared to their ICE vehicle pair, big EVs have lower TCO, higher sales, and seem to be less price responsive than small EVs. Three country groups can be distinguished according to the level of fiscal incentives and their impact on TCO and EV sales. In Norway, incentives led to the lowest TCO for the EVs. In the Netherlands, France, and UK the TCO of EVs is close to the TCO of the ICE pairs. In the other countries the TCO of EVs exceeds that of the ICE vehicles. We found that exemptions from flat taxes favour big EVs, while lump-sum subsidies favour small EVs.
Electric vehicles (EV), as a promising way to reduce the greenhouse effect, have been researched extensively. With improvements in the areas of power electrics, energy storage and support, the plug-in hybrid electric vehicle (PHEV) provides competitive driving range and fuel economy compared to the internal combustion engine vehicle (ICEV). Operating with optimised control strategies or utilising the concept of the energy management system (EMS), the efficiency of the PHEV could be significantly improved. In this review paper, the operating process of the various types of EVs will be explained. Battery technology and supercapacitor technology will also be discussed as a possibility to increase the energy capacity of PHEV.
Electric vehicles (EV), as a promising way to reduce the greenhouse
effect, have been researched extensively. With improvements in the areas
of power electrics, energy storage and support, the plug-in hybrid electric
vehicle (PHEV) provides competitive driving range and fuel economy
compared to the internal combustion engine vehicle (ICEV). Operating with
optimised control strategies or utilising the concept of the energy management
system (EMS), the efficiency of the PHEV could be significantly improved.
In this review paper, the operating process of the various types of EVs will be
explained. Battery technology and supercapacitor technology will also be
discussed as a possibility to increase the energy capacity of PHEV.
Particulate matter (PM) exposure has been linked to adverse health effects by numerous studies. Therefore, governments have been heavily incentivising the market to switch to electric passenger cars in order to reduce air pollution. However, this literature review suggests that electric vehicles may not reduce levels of PM as much as expected, because of their relatively high weight. By analysing the existing literature on non-exhaust emissions of different vehicle categories, this review found that there is a positive relationship between weight and non-exhaust PM emission factors. In addition, electric vehicles (EVs) were found to be 24% heavier than equivalent internal combustion engine vehicles (ICEVs). As a result, total PM10 emissions from EVs were found to be equal to those of modern ICEVs. PM2.5 emissions were only 1-3% lower for EVs compared to modern ICEVs. Therefore, it could be concluded that the increased popularity of electric vehicles will likely not have a great effect on PM levels. Non-exhaust emissions already account for over 90% of PM10 and 85% of PM2.5 emissions from traffic. These proportions will continue to increase as exhaust standards improve and average vehicle weight increases. Future policy should consequently focus on setting standards for non-exhaust emissions and encouraging weight reduction of all vehicles to significantly reduce PM emissions from traffic.
The deployment of electric vehicle (EV) as the new era of green transportation needs a continuous support on charging infrastructure. Charging mechanism could be provided in residential area or in the public area. In public area, charging infrastructure could be in the form of fixed charging station (FCS) or delivered as a mobile charging station (MCS). MCS unit should be in the form of truck-type vehicle equipped with several charging outlet to conduct charging for EVs inside or outside FCS area. When conducting off-grid charging outside FCS area, MCS power source would come from energy storage equipped inside the MCS. There are several energy storages widely used in EV application such as battery and ultracapacitor. This paper determined that Lithium–iron phosphate (LiFePO4) is the most suitable battery and electric double-layer capacitor (EDLC) is the most appropriate ultracapacitor for MCS application. The combination of battery and ultracapacitor provide current and voltage respond which is fit to conduct fast or ultrafast charging. This paper also provides an energy storage system to facilitate battery and ultracapacitor to be installed in MCS truck utilizing back compartment, side panels, and dash board.
Purpose
Introducing a geopolitical-related supply risk (GeoPolRisk) into the life cycle sustainability assessment (LCSA) framework adds a criticality aspect to the current life cycle assessment (LCA) framework to more meaningfully address direct impacts on Natural Resource AoP. The weakness of resource indicators in LCA has been the topic of discussion within the life cycle community for some time. This paper presents a case study on how to proceed towards the integration of resource criticality assessment into LCA under the LCSA. The paper aims at highlighting the significance of introducing the GeoPolRisk indicator to complement and extend the established environmental LCA impact categories.
Methods
A newly developed GeoPolRisk indicator proposed by Gemechu et al., J Ind Ecol (2015) was applied to metals used in the life cycle of an electric vehicle, and the results are compared with an attributional LCA of the same resources. The inventory data is based on the publication by Hawkins et al., J Ind Ecol 17:53–64 (2013), which provides a current, transparent, and detailed life cycle inventory data of a European representative first-generation battery small electric vehicle.
Results and discussion
From the 14 investigated metals, copper, aluminum, and steel are the most dominant elements that pose high environmental impacts. On the other hand, magnesium and neodymium show relatively higher supply risk when geopolitical elements are considered. While, the environmental indicator results all tend to point the same hotspots which arise from the substantial use of resources in the electric vehicle’s life cycle, the GeoPolRisk highlights that there are important elements present in very small amounts but crucial to the overall LCSA. It provides a complementary sustainability dimension that can be added to conventional LCA as an important extension within LCSA.
Conclusions
Resource challenges in a short-term time perspective can be better addressed by including social and geopolitical factors in addition to the conventional indicators which are based on their geological availability. This is more significant for modern technologies such as electronic devices in which critical resources contribute to important components. The case study advances the use of the GeoPolRisk assessment method but does still face certain limitations that need further elaboration; however, directions for future research are promising.
This paper presents a new method for development of electronic differentials for electric racing vehicles. Most electronic differential solutions focus on maintaining the vehicle stability as the first and dominant priority, and are designed to keep some stability-related quantity (e.g. wheel slip) in a “safe region”. With racing cars however, the main focus is on the responsiveness of the vehicle and its capability to cope with extreme steering and accelerating demands from the driver. Our focus is on designing a controller to achieve neutral-steer (avoiding over- or under-steer) in race car driving conditions. We show a direct relationship between the steering condition and the difference of the longitudinal tire-road friction forces for the driven wheels. We mathematically derive the desired difference in the tire-road frictions that would achieve neutral-steer and show that it is directly related to the difference in the driving torques provided by motors. A closed-loop-control system is proposed for direct control of the motor torques. The simulation results show a close-to-neutral steering performance of the car (while maintaining its stability) in challenging steering scenarios.
Keywords: Tire/road noise Close Proximity method (CPX) Rubberized surface Noise mitigation actions a b s t r a c t The use of road surfaces with low noise emission characteristics is one of the actions mostly applied all over the world to decrease the number of road traffic noise annoyed people. Since many Italian roads are going to be paved with such surfaces, the LEOPOLDO project (funded by the Tuscany Region and the Italian Ministry of Transportation) was planned to check the efficacy in time of this action. Among all solutions, rubberized road surface is one of the most applied in USA, Canada, Europe and Asia. This paper describes results obtained by monitoring four rubberized surfaces one year after the laying and by evaluating the time stability of LEOPOLDO one by means of the Close Proximity method (CPX). All surfaces here analyzed are laid in real scenarios, so the actual efficacy of this action is evaluated. The results on the LEOPOLDO surface show spatial homogeneity, a good time stability and a significant noise emission reduction. Instead, analysis of the four rubberized surfaces shows variability in the results, probably due to the pavement installation quality, as supported by the data. Thus, the rubberized road surface looks to be a very efficient mitigation technology, providing the installation have been carried out with care and proficiency.
Since the late 19th century until recently several electric vehicles have been designed, manufactured and used throughout the world. Some were just prototypes, others were concept cars, others were just special purpose vehicles and lately, a considerable number of general purpose cars has been produced and commercialized. Since the mid nineties the transportation sector emissions are being increasingly regulated and the dependency on oil and its price fluctuations originated an increasing interest on electric vehicles (EV). A wide research was made on existing electric/hybrid vehicle models. Some of these vehicles were just in the design phase, but most reached the prototype or full market production. They were divided into several types, such as NEVs, prototypes, concept cars, and full homologated production cars. For each type of vehicle model a technical historic analysis was made. Data related to the vehicle configuration as well as the embedded systems were collected and compared. Based on these data future prospect of evolution was subsequently made. The main focus was put on city vehicles and long range vehicles. For city vehicles the market approach normally consists in the use of full electric configuration while for the latter, the hybrid configuration is commonly used. The electrical systems and combustion engines found in these vehicles are compared in order to forecast the evolution trend in terms of specifications and performance of the whole vehicle and of each system.
Limited Traffic Zone (LTZ) is a planning strategy that is more and more adopted by municipalities in
Europe to improve their environmental conditions. It consists in the prohibition for traditional vehicles to
circulate in specific areas. Although the main aim is to tackle air pollution problems, positive effects are
registered in terms of reduction of noise annoyance and in terms of improved “quality of life” if specific
conditions are respected. On the other side under the drive of the global market, the number of circulating
electric vehicles in urban sites is also increasing. In the next years we expect to experience a new and not
well-known urban soundscape.
In this paper is presented an overview of recent urban projects and policies that deal with noise control
and how these experiences will match into the next years with the sound characteristics of new electric
vehicles for private and public transportation.
Technology innovation in electric vehicles is of significant interest to researchers, companies and policy-makers of many countries. Electric vehicles integrate various kinds of distinct technologies and decomposing the overall electric vehicle field into several key domains allows determination of more detailed, valuable information. To provide both broader and more detailed information about technology development in the EV field, unlike most previous studies on electric vehicle innovation which analyzed this field as a whole, this research decomposed the electric vehicle field into domains, which are power electronics, battery, electric motor as well as charging and discharging subdomains and then further extracted the subdomains. Furthermore, In addition, the improvement rates, technology trajectories and major patent assignees in these domains and key subdomains are determined using patents extracted for each domain from the US patent system. The main findings are: (1) The estimated rates of performance improvement per year are 18.3% for power electronics, 7.7% for electric motors, 23.8% for charging and discharging and 11.7% for batteries. The relatively lower improvement rate for electric motors and batteries suggests their potential to hinder the popularization of electric vehicles. Besides, as for the subdomains, the relatively higher technology improvement rate of lithium-ion battery or permanent magnet motor in its domain supports the current trend of battery or motor type quantitively from a patent analysis view. A possible implication for the policy makers encouraging EV development is to issue more incentive plans for innovations in the battery and electric motor domains, especially for lithium-ion battery and permanent magnet motor. (2) The technology trajectories depict the development of four critical subdomains over time, which quantitively proves the focuses and emerging topics of the subdomains and thereby provide guidance to research topic selection. For example, the silicon negative electrode is a promising topic in the subdomain of lithium-ion battery. (3) The key players in the four critical subdomains appear to be Toyota and Honda in hybrid power electronics, E-One Moli Energy Corp in lithium-ion batteries, Panasonic in Permanent Magnet motors and Toyota in discharging. The key players found by the main path method from the view of innovation are also important players in EV from the market view. Other market participants should pay more attention to the adjustment of business strategy of these companies to monitor the market, and make effort to invent important EV related technologies.
Pavement data collection is the most expensive and time consuming component of Pavement Management System (PMS). Thus, possible methods of minimizing the need of such data might be critical in reducing pavement condition monitoring costs. Also the ability to relate pavement performance prediction models (frequently roughness based) to hot mix asphalt field performance models (distress based) provides valuable conclusions and input in pavement design, performance assessment, maintenance and rehabilitation strategies. Objective of this study was to examine whether specific distresses can influence roadway profile so as to be able to relate the two. The influence of pavement distresses on road profile has been investigated over the years. However, past studies provided conflicting conclusions. Thus, in this study an alternative approach was considered due to the availability of high quality and detailed distress data collected with the Laser Crack Measurement System (LCMS) of the Automatic Road Analyzer, ARAN. As it was expected, specific distresses have higher impact in longitudinal roughness since they are present on the roadway surface at regular intervals (i.e., specific frequencies). For this reason, instead of using summary indexes (i.e., International Roughness Index (IRI), Pavement Condition Index (PCI)), the Power Spectral Density (PSD) of the roadway profile at specific frequency bandwidths was considered along with distresses. The analysis indicated that a specific subset of distresses is affecting roughness at definite wavelength frequencies. Alligator cracking and rutting standard deviation provided the best correlation. IRI was correlated better with distress (e.g. rutting standard deviation) at lower profile frequencies. At high frequency domain (i.e., below 0.8 m wavelengths) better correlation between IRI and high severity cracking was observed through the PSD. Considering multiple frequencies in the regression models between roughness and distresses, the goodness of fit has not necessarily improved. However, the role of different bandwidths was evident. In addition to the specific results, the methodology presented in this study can be used elsewhere to assess potential relations between pavement roughness and distress components.
To overcome adoption barriers and promote battery electric vehicles (BEVs) as an energy efficient consumer transportation option, a number of states offer subsidies to consumers for BEVs. We use a national data set of vehicle registrations and state-level financial incentives to assess the impact of vehicle purchase subsidies on adoption using both difference-in-differences and synthetic controls methods. We find that incentives offered as direct purchase rebates generate increased levels of new BEV registrations at a rate of approximately 8 percent per thousand dollars of incentive offered. Between 2011 and 2015, vehicle rebate incentives are associated with an increase in overall BEV registrations of approximately 11 percent. Our findings indicate incentives offered as state income tax credits do not have a statistically significant effect on BEV adoptions, though we caution this may be a result of limited temporal variation in BEV incentives across our sample. Responses to rebate incentives do not differ significantly by the make of the vehicle purchased (i.e., Tesla and non-Tesla vehicles). We combine our results with recent assessments of marginal environmental costs of electric vehicle charging and measure net welfare effects of BEV subsidy programs. Our analysis indicates these programs are not welfare-improving if only considering benefits associated with avoided emissions. Additional benefits associated with long-term market growth, production cost savings, network externalities, or accelerated innovation could substantially impact the net welfare outcomes.
Suspension shock absorber squeak noise is becoming increasingly apparent within the overall noise level of all-electric vehicles (EVs) due to the extensive reduction in power system noise. Although the early identification of shock absorber squeak noise via bench tests can save costs and time, such identification remains a challenge for the industry. In this paper, a novel method for identifying and predicting EV shock absorber squeak noise is proposed. In contrast to other studies on shock absorber noise that focus on highly complex designs and feature extraction, this study uses the original time signals and frequency spectra to predict the shock absorber squeak noise based on deep neural networks (DNNs). To implement this method, an EV road test is conducted on five different pavements, and the grade evaluation method (GEM) is applied in a subjective evaluation of the annoyance of the shock absorber squeak noise. The vibration signals of the shock absorber piston rod are collected and preprocessed via a bench test. Then, a DNN is developed to automatically extract the shock absorber squeak noise feature and intelligently identify the subjective annoyance (SA) grade of the squeak noise. This novel identification method effectively solves the problem in which the annoyance level cannot be evaluated via the GEM by relying on the rich auditory experience of the evaluation subject. In the validation analysis, the DNN outperforms two other intelligent methods, the genetic algorithm-back propagation neural network (GA-BPNN) and the genetic algorithm-support vector machine (GA-SVM), based on a confusion matrix and an error analysis.
This paper shows the results of an experimental study concerning the effect of introduction of basalt fibres in asphalt mixtures for surface course, mainly with regard to those to be used in urban areas, for dedicated bus lanes. Surface layers, where tire-pavement interactions occur, have to provide different properties such as high friction (very important for users’ safety), stability, resistance to meteorological agents, and contribution to the overall pavement performances. Considering that basalt fibres provide considerable physical and mechanical properties and above all high abrasion resistance, scope of the study is to evaluate the effects of these fibres on mixtures properties, especially in terms of friction and rutting behaviour. For this purpose, after setting up a model to estimate the impact of fibres on asphalt film thickness and richness modulus, the mixtures produced were subjected to laboratory tests for performance evaluation in terms of rutting resistance and the surface texture. The test results allow drawing some important conclusions about basalt fibre-modified asphalt mixtures: in particular, these mixtures show better performance with reference to permanent deformation resistance when compared with the traditional mixture; moreover, the introduction of basalt fibres involves a “flattening” of the profile texture and a lower macrotexture. Interestingly, fibres addition is likely to slightly increase the micro-texture. This point calls for further study.
There is no doubt that electrified vehicles are superseding internal combustion engine vehicles for road transportation. Among them, electric vehicles (EVs) have been identified as the greenest road transportation while hybrid EVs have been tagged as the super ultra-low emission vehicles. In this paper, the definition, classification, merits and demerits of electric and hybrid vehicles are first introduced. Then, after revealing their multidisciplinary technologies and development trends, the state-of-the-art electromagnetics research in electric and hybrid vehicles are discussed, with emphasis on electric motors for electric propulsion, electric machine systems for hybrid propulsion, wireless power transfer technologies for park-and-charge a well as move-and-charge, electromagnetic interference and compatibility issues in EVs, electromechanical flywheels for energy storage and magnetic sensors for EV operation. Meanwhile, the development trend of these research areas is revealed.
The increasingly stringent statutory requirements for reducing CO2 emissions and pollutants from vehicles, is increasing the necessity for hybridization and electrification of the powertrain.
This paper presents certain considerations related to noise, vibration and harshness issues on modern motor vehicles. The first, practical aspect was used toward structuring of the acquired knowledge and relationships, required for proper problem diagnosis. On the other hand, advanced signal analyses are considered. The influence on human body is processed and certain noise and vibration analyzers are presented. This synergy of scientific and applicative approach represents a basis for further research related to this important automotive branch. © Faculty of Mechanical Engineering, Belgrade. All rights reserved.
The CNOSSOS-EU method is recommended in Europe for environmental noise prediction. In regards to
road traffic, it includes vehicle noise emission models implicitly referring to internal combustion vehicles.
The development of electrically driven vehicles calls for the future consideration of these vehicles in
prediction models. On the basis of experimental data, the study reported in this paper proposes a noise
emission model for extending CNOSSOS-EU to light electric vehicles. Correction terms to be applied to the
propulsion noise component are determined. Investigations on a sample of tyres with good rolling resistance
performance, which is a main tyre selection criterion on these vehicles, indicated that no correction
is required for the rolling noise component. Differences between the noise emission from conventional
vehicles and electric vehicles are discussed for several road surfaces. Owing to the limited vehicle sample
as well as transitional statements, this new model for electric vehicles running at constant speed over
20 km/h should be considered as a first step towards the definition of this vehicle technology in
CNOSSOS-EU.
The objective of this paper is to study the variability of on-site acoustic measurements in non-normal conditions, as a function of the angle. A porous European mix was investigated. In order to reject the hypothesis that the cause of the variations in the acoustic properties is the surface inhomogeneity, texture properties were investigated according to the standard ISO 13473-1 and ISO/CD TS 13473-4. The acoustic absorption coefficient was measured according to ISO 13472-1. Results were compared and analysed in terms of averages and standard deviations. Result analyses may allow us to derive how absorption properties may vary as a function of the angle of incidence (under the hypothesis of homogeneous surface texture of the friction course). A tentative theoretical framework for explaining the dependence of acoustic absorption on incidence angle was formulated. The outcomes of this study are expected to benefit both practitioners and researchers. © 2014 © 2014 Taylor & Francis.
Acoustic-based mix design is still far from achieving a clear and accepted rationale. The three main dominions (generation, absorption, propagation) which affect pavement acoustic performance involve a number of acoustic parameters. Their relationship with pavement properties is scarcely or insufficiently known. In more detail, the parameters that define the acoustic coupling between the two phases that comprise a porous material are: porosity, resistivity, tortuosity, and viscous and thermal factors. Consequently, the spectrum of a pavement absorption coefficient depends, in particular, on tortuosity, whose relationship with HMA (hot mix asphalt) bulk properties is still an issue.
The transition to electric vehicles (EV) faces two major barriers. On one hand, EV batteries are still expensive and limited by range, owing to the lack of technology breakthrough. On the other hand, the underdeveloped supporting infrastructure, particularly the lack of fast refueling facilities, makes EVs unsuitable for medium and long distance travel. The primary purpose of this study is to better understand these hurdles and to develop strategies to overcome them. To this end, a conceptual optimization model is proposed to analyze travel by EVs along a long corridor. The objective of the model is to select the battery size and charging capacity (in terms of both the charging power at each station and the number of stations needed along the corridor) to meet a given level of service in such a way that the total social cost is minimized. Two extensions of the base model are also considered. The first relaxes the assumption that the charging power at the stations is a continuous variable. The second variant considers battery swapping as an alternative to charging. Our analysis suggests that (1) the current paradigm of charging facility development that focuses on level 2 charging delivers poor level of service for long distance travel; (2) the level 3 charging method is necessary not only to achieve a reasonable level of service, but also to minimize the social cost; (3) investing on battery technology to reduce battery cost is likely to have larger impacts on reducing the charging cost; and (4) battery swapping promises high level of service, but it may not be socially optimal for a modest level of service, especially when the costs of constructing swapping and charging stations are close.
Wear at the interface between flexible pavements and tires influences pavement life, pavement cycle costs, and tire consumption, and is a source of environmental harm. Wear-related processes evolve over time and are affected by a number of boundary conditions, such as interface fluids, water and fuels. We develop a model explaining and predicting mass losses in flexible pavements under carefully controlled conditions, and with estimation of the related environmental costs. We also employed an accelerated loading test. Under normal conditions, the environmental impact of pavement wear is not greatly influenced by mix type or volumetrics. Indeed, the presence of hazmat materials, traditional, dense mixes have an environmental impact that is appreciably lower than that of porous European mixes.
Battery Electric Vehicles vs. Internal Combustion Engine Vehicles. A United States-Based Comprehensive Assessment
- brennan
J. W. Brennan and B. Timothy E., "Battery Electric Vehicles vs.
Internal Combustion Engine Vehicles. A United States-Based
Comprehensive Assessment.," 2016.
The concept of adaptive AVAS - results from a small test program
- berge
T. Berge and F. Haukland, "The concept of adaptive AVAS -results
from a small test program," INTER-NOISE 2019 MADRID -48th Int.
Congr. Exhib. Noise Control Eng., no. 2, 2019.
Life Cycle Analysis of the Climate Impact of Electric Vehicles
- messagie
M. Messagie, "Life Cycle Analysis of the Climate Impact of Electric
Vehicles," Transp. Environ., pp. 1-14, 2017.
Noise emission of electric and hybrid electric vehicles?: deliverable FOREVER ( n ° Forever WP2 _ D2-1-V4 ) To cite this version?: HAL Id?: hal-02177735 Noise emission of electric and hybrid electric vehicles
- pallas
M. Pallas et al., "Noise emission of electric and hybrid electric
vehicles : deliverable FOREVER ( n ° Forever WP2 _ D2-1-V4 ) To
cite this version : HAL Id : hal-02177735 Noise emission of electric
and hybrid electric vehicles," 2015.
City Hush DELIVERABLE 3.4.2 Developing quiet tyre designs for quiet road surfaces Low noise DualQ tyre combined with electric vehicle
- lundberg
O. Lundberg, "City Hush DELIVERABLE 3.4.2 Developing quiet tyre
designs for quiet road surfaces Low noise DualQ tyre combined with
electric vehicle," 2011.
Le emissioni di CO2 delle auto elettriche e delle auto con motore a combustione interna. Un confronto per l’Italia tramite l’analisi del ciclo di vita
- danielis
R. Danielis, "Le emissioni di CO2 delle auto elettriche e delle auto con
motore a combustione interna. Un confronto per l'Italia tramite
l'analisi del ciclo di vita," Work. Pap. SIET, pp. 1-13, 2016.
NVH analysis techniques for design and optimization of hybrid and electric vehicles
- campillo-davo
N. Campillo-Davo and A. Rassili, "NVH analysis techniques for design
and optimization of hybrid and electric vehicles," 2016.
Qcity Project Deliverable 5.16 An analytical model for calculating the vibration response and sound radiation from an in-service tyre/road system: The analytical model and calculated results
- dowling
A. Dowling, "Qcity Project Deliverable 5.16 An analytical model for
calculating the vibration response and sound radiation from an inservice tyre/road system: The analytical model and calculated results,"
2008.
Grid Electrified Vehicles: Performance, Design and Environmental Impacts
- martins
J. Martins et al., "Grid Electrified Vehicles: Performance, Design and
Environmental Impacts," pp. 209-232, 2013.
Comparison of dynamic characteristics of electric and conventional road vehicles
- Semir Beganović
- Suada Dacić
Semir Beganović and Suada Dacić, "Comparison of dynamic
characteristics of electric and conventional road vehicles," First Int.
Green Des. Conf., pp. 149-155, 2012.
A Comparison of Electric Vehicles and Conventional Automobiles?: Costs and Quality Perspective
- palinski
M. Palinski, "A Comparison of Electric Vehicles and Conventional
Automobiles : Costs and Quality Perspective," Novia, p. 60, 2017.
Simulation-based design of a steerable acoustic warning device to increase (H) EV detectability while reducing urban noise pollution
- van genechten
B. Van Genechten and A. P. Berkhoff, "Simulation-based design
of a steerable acoustic warning device to increase (H) EV detectability
while reducing urban noise pollution," Transp. Res. Arena, 2014.
Qcity Project Deliverable 5.8 part 2 Validation Site Stockholm – Quiet Vehicles Quantification of driveline and tyre/road noise from a hybrid electric passenger car (Toyota Prius)
- stenlund
F. Stenlund and N.-Å. Nilsson, "Qcity Project Deliverable 5.8 part 2
Validation Site Stockholm -Quiet Vehicles Quantification of driveline
and tyre/road noise from a hybrid electric passenger car (Toyota
Prius)," 2008.
Measurement of noise from electrical vehicles and internal combustion engine vehicles under urban driving conditions
- iversen
L. M. Iversen, "Measurement of noise from electrical vehicles and
internal combustion engine vehicles under urban driving conditions,"
Compett, pp. 2129-2134, 2012.
Electric vehicles from life cycle and circular economy perspectives
- Agency European Environmental
European Environmental Agency, "Electric vehicles from life cycle
and circular economy perspectives TERM 2018: Transport and
Environment Reporting Mechanism (TERM) report," 2018.
Analysis of Various NHV Sources of a Combustion Engine
- singh