Download or read book Performance Effects and Causal Mechanisms of Mid channel Congestion in Diesel Particulate Filters written by Ian Patrick Tracy and published by . This book was released on 2021 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt: The diesel particulate filter (DPF) is a ~$5,000-$50,000 USD critical component of aftertreatment systems installed in diesel engine-powered vehicles. The device is designed to trap particles emitted by the diesel combustion process in order to prevent their release into the surrounding environment, thereby reducing pollution levels and mitigating greenhouse gas emissions. Increasing stringency of emissions regulations has progressively necessitated the installation of DPFs on diesel-powered vehicles over the past few years, with the DPF market expected to remain significant in size at least through 2025. While DPFs nominally operate by trapping and accumulating incoming PM continuously in the far downstream plug region of the filter channels so that no gaps form between trapped particulate matter (PM) agglomerates, both real-world field and laboratory bench tests have demonstrated that channel-spanning ash agglomerates form well upstream of the end plug region, prematurely clogging the mid-channel region. This effectively renders useless the remaining open space in the channel downstream of the blockage location. In addition to mid-channel congestion, this adverse phenomenon is referred to in the literature interchangeably as mid-channel collapse (MCC), mid-channel clogging, and mid-channel deposits (MCD). MCC, due to accelerated filling of the filter channels, often results in significantly reduced DPF lifetime and performance (i.e. increased backpressure yielding depressed fuel economy), both of which prove costly for diesel vehicle operators. Existing hypotheses regarding causality of MCC are largely based on inconclusive empirical observations, and not substantiated by fundamental quantitative analysis. The primary contributions of this dissertation include: 1) summarizing hypothesized causal mechanisms of MCC with an emphasis on sintering as a primary driver thereof, 2) introducing a method by which to analyze X-Ray CT scans that show MCC in DPF channels, 3) assessing the performance penalty associated with MCC by correspondingly extending the industry standard model for pressure drop across a DPF, and 4) suggesting modifications to the DPF regeneration process in order to prevent sintering of ash agglomerates to the DPF side walls, based on an efficient reformulation of the prevalent temperature history model of the DPF that solves for both flow and temperature conditions inside filter channels over time during active regeneration.

Download or read book Diesel Particulate Filter Technology written by Timothy V Johnson and published by SAE International. This book was released on 2007-03-28 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt: Until recently, the complexity of the Diesel Particulate Filter (DPF) system has hindered its commercial success. Stringent regulations of diesel emissions has lead to advancements in this technology, therefore mainstreaming the use of DPFs in light- and heavy-duty diesel filtration applications. This book covers the latest and most important research in DPF systems, focusing mainly on the advancements of the years 2002-2006. Editor Timothy V. Johnson selected the top 29 SAE papers covering the most significant research in this technology.

Download or read book Filtration and Regeneration Mechanisms in Diesel Particulate Filters Influence on Filter Performance written by Niklas M. Schmidt and published by . This book was released on 2006 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Investigations of Ash Layer Characteristics and Ash Distribution in a Diesel Particulate Filter Using Novel Lubricant Additive Tracers written by Ryan Michael Morrow and published by . This book was released on 2010 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt: Diesel particulate filters (DPF) are currently widely used in various applications as a means of collecting particulate matter in order to meet increasingly stringent particle emissions regulations. Over time, the DPF slowly accumulates incombustible material or ash, mostly from the metallic additives present in the engine lubricant. This build up of accumulated ash leads to an increase in flow restriction and therefore an increase in pressure drop along the DPF. The increased pressure drop negatively impacts engine performance and fuel economy, and it also requires eventual filter removal for ash cleaning. While the major effects of ash accumulation on DPF performance are known, the fundamental underlying mechanisms are not. This work is focused on understanding key mechanisms, such as the soot deposition and the ash formation, accumulation, and distribution processes, which play a major role in determining the magnitude of the ash effect on DPF pressure drop. More specifically, it explores the location of ash deposit accumulation inside the DPF channels, whether in a layer along the filter walls or packed in a plug at the rear of the channels, which is one of the key factors controlling DPF pressure drop. A specialized experiment was set up by running three different lubricants, each with its own unique additive tracer, sequentially through a diesel burner system. Scanning electron microscopy (SEM) was used to analyze the evolution of the ash deposits in the DPF samples in order to explain the specific mechanisms and processes controlling ash properties and their effect on DPF pressure drop. The experimental results were compared and correlated with previous DPF test data and theoretical models, providing additional insight to optimize diesel particulate filter performance. The results are useful in optimizing the design of the engine, aftertreatment, and lubricant systems for future diesel engines, balancing the requirements of additives for adequate engine protection with the requirements for robust after treatment systems.

Download or read book Modeling and Interpreting the Observed Effects of Ash on Diesel Particulate Filter Performance and Regeneration written by Yujun Wang (Ph. D.) and published by . This book was released on 2014 with total page 137 pages. Available in PDF, EPUB and Kindle. Book excerpt: Diesel particulate filters (DPF) are devices that physically capture diesel particulates to prevent their release to the atmosphere. Diesel particulate filters have seen widespread use in on- and off-road applications as an effective means for meeting increasingly stringent particle emissions regulations. Although the soot deposit can be removed by regeneration, the incombustible material - ash, primarily derived from metallic additives in the engine lubricant, accumulates in the DPF channels with the increasing vehicle mileage or equivalent running hours. Ash accumulation inside filter increases the flow restriction and reduces the filter soot storage capacity, which results in higher filter regeneration frequencies and larger engine fuel penalty. Combined with experimental observations, DPF models are built to investigate the fundamental mechanisms of DPF aging process. The DPF soot and ash loading model, based on porous media filtration theory, is applied to understand the soot deposition across the substrate wall with soot and ash cake layer formation. DPF models are also used to investigate the process of ash transport and catalyst deactivation with increasing ash load level. DPF ash aging is found to have negative effect on passive regeneration due to the catalyst deactivation and diffusion resistance of ash cake layer. Besides, at given amount of ash load, the effects of ash spatial distribution on DPF performance are studied via simulation. It is found that the ash end plug has significant influences on DPF pressure drop while ash radial and axial distributions have minor effects. At known ash and substrate property, DPF performance can be optimized according the sensitivity map developed from this study. DPF model is beneficial to interpret the experimental observations and it is applied to predict the effects of certain factors, like flow rate and deposit level, on DPF performance. At the same time, modeling results are useful in optimizing the design of the combined engine-aftertreatment-lubricant system for future diesel engines and in understanding the requirements for robust aftertreatment systems.

Download or read book Non exhaust Particulate Emissions from Road Transport An Ignored Environmental Policy Challenge written by OECD and published by OECD Publishing. This book was released on 2020-12-07 with total page 149 pages. Available in PDF, EPUB and Kindle. Book excerpt: Non-exhaust emissions of particulate matter constitute a little-known but rising share of emissions from road traffic and have significant negative impacts on public health. This report synthesizes the current state of knowledge about the nature, causes, and consequences of non-exhaust particulate emissions. It also projects how particulate matter emissions from non-exhaust sources may evolve in future years and reflects on policy instrument mixes that can address this largely ignored environmental issue.

Download or read book Toxicological Profile for Toluene written by and published by . This book was released on 2000 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Automotive Air Pollution written by and published by World Bank Publications. This book was released on 1990 with total page 131 pages. Available in PDF, EPUB and Kindle. Book excerpt: Automotive air pollution will intensify with increasing urbanization and the rapid pace of motorization in developing countries. Without effective measures to curb air pollution, some 300-400 million city dwellers in developing countries will become exposed to unhealthy and dangerous levels of air pollution by the end of the century. Administratively simple policies that encourage clean fuels and better traffic management are the most promising approach to controlling vehicle pollutant emissions in developing countries.

Download or read book Negative Emissions Technologies and Reliable Sequestration written by National Academies of Sciences, Engineering, and Medicine and published by National Academies Press. This book was released on 2019-04-08 with total page 511 pages. Available in PDF, EPUB and Kindle. Book excerpt: To achieve goals for climate and economic growth, "negative emissions technologies" (NETs) that remove and sequester carbon dioxide from the air will need to play a significant role in mitigating climate change. Unlike carbon capture and storage technologies that remove carbon dioxide emissions directly from large point sources such as coal power plants, NETs remove carbon dioxide directly from the atmosphere or enhance natural carbon sinks. Storing the carbon dioxide from NETs has the same impact on the atmosphere and climate as simultaneously preventing an equal amount of carbon dioxide from being emitted. Recent analyses found that deploying NETs may be less expensive and less disruptive than reducing some emissions, such as a substantial portion of agricultural and land-use emissions and some transportation emissions. In 2015, the National Academies published Climate Intervention: Carbon Dioxide Removal and Reliable Sequestration, which described and initially assessed NETs and sequestration technologies. This report acknowledged the relative paucity of research on NETs and recommended development of a research agenda that covers all aspects of NETs from fundamental science to full-scale deployment. To address this need, Negative Emissions Technologies and Reliable Sequestration: A Research Agenda assesses the benefits, risks, and "sustainable scale potential" for NETs and sequestration. This report also defines the essential components of a research and development program, including its estimated costs and potential impact.

Download or read book Non Exhaust Emissions written by Fulvio Amato and published by Academic Press. This book was released on 2018-01-02 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt: Non-Exhaust Emissions: An Urban Air Quality Problem for Public Health comprehensively summarizes the most recent research in the field, also giving guidance on research gaps and future needs to evaluate the health impact and possible remediation of non-exhaust particle emissions. With contributions from some of the major experts and stakeholders in air quality, this book comprehensively defines the state-of-the-art of current knowledge, gaps and future needs for a better understanding of particulate matter (PM) emissions, from non-exhaust sources of road traffic to improve public health. PM is a heterogeneous mix of chemical elements and sources, with road traffic being the major source in large cities. A significant part of these emissions come from non-exhaust processes, such as brake, tire, road wear, and road dust resuspension. While motor exhaust emissions have been successfully reduced by means of regulation, non-exhaust emissions are currently uncontrolled and their importance is destined to increase and become the dominant urban source of particle matter by 2020. Nevertheless, current knowledge on the non-exhaust emissions is still limited. This is an essential book to researchers and advanced students from a broad range of disciplines, such as public health, toxicology, atmospheric sciences, environmental sciences, atmospheric chemistry and physics, geochemistry, epidemiology, built environment, road and vehicle engineering, and city planning. In addition, European and local authorities responsible for air quality and those in the industrial sectors related to vehicle and brake manufacturing and technological remediation measures will also find the book valuable. Acts as the first book to explore the health impacts of non-exhaust emissions Authored by experts from several sectors, including academia, industry and policy Gathers the relevant body of literature and information, defining the current knowledge, gaps and future needs

Download or read book Good Economics for Hard Times written by Abhijit V. Banerjee and published by PublicAffairs. This book was released on 2019-11-12 with total page 398 pages. Available in PDF, EPUB and Kindle. Book excerpt: The winners of the Nobel Prize show how economics, when done right, can help us solve the thorniest social and political problems of our day. Figuring out how to deal with today's critical economic problems is perhaps the great challenge of our time. Much greater than space travel or perhaps even the next revolutionary medical breakthrough, what is at stake is the whole idea of the good life as we have known it. Immigration and inequality, globalization and technological disruption, slowing growth and accelerating climate change--these are sources of great anxiety across the world, from New Delhi and Dakar to Paris and Washington, DC. The resources to address these challenges are there--what we lack are ideas that will help us jump the wall of disagreement and distrust that divides us. If we succeed, history will remember our era with gratitude; if we fail, the potential losses are incalculable. In this revolutionary book, renowned MIT economists Abhijit V. Banerjee and Esther Duflo take on this challenge, building on cutting-edge research in economics explained with lucidity and grace. Original, provocative, and urgent, Good Economics for Hard Times makes a persuasive case for an intelligent interventionism and a society built on compassion and respect. It is an extraordinary achievement, one that shines a light to help us appreciate and understand our precariously balanced world.

Download or read book Research Priorities for Airborne Particulate Matter written by National Research Council and published by National Academies Press. This book was released on 1998-05-30 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt: New National Ambient Air Quality Standards for airborne particles smaller than 2.5 micrometers, called PM2.5, were issued by the U.S. Environmental Protection Agency (EPA) amidst scientific uncertainty and controversy. In response to a request from Congress, Research Priorities for Airborne Particulate Matter, the first of four books in a series, offers a conceptual framework for an integrated national program of particulate-matter research, identifies the 10 most critical research needs linked to key policy-related scientific uncertainties, and describes the recommended timing and estimated costs of such research. The committee concludes that EPA should devote more resources to investigating the relationships between fixed-site outdoor monitoring data and actual human breathing-zone exposures to ambient particulate matter and to identifying the most biologically important constituents and characteristics of particulate matter through toxicological studies. The recommended research activities are critical to determining actual exposures of human subpopulations most susceptible to harm from the most hazardous constituents of particulate matter. Future research will be an investment in public health and a means to ensure that resources spent on control technology and regulatory compliance will have a reasonable probability of success.

Download or read book Toxicological Profile for Tetrachloroethylene written by and published by . This book was released on 1997 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Toxicological Profile for Copper written by and published by . This book was released on 2004 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Toxicological Profile for Pentachlorophenol written by and published by . This book was released on 2001 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Growing Cooler written by Reid H. Ewing and published by Urban Land Institute. This book was released on 2008 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt: Based on a comprehensive study review by leading urban planning researchers, this investigative document demonstrates how urban development is both a key contributor to climate change and an essential factor in combating it -- by reducing vehicle greenhouse gas emissions.

Download or read book Maritime Traffic Effects on Biodiversity in the Mediterranean Sea written by Ameer Abdulla and published by IUCN. This book was released on 2008 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt: