Dissertations / Theses on the topic 'Diesel trucks'

Thesis (M.S.)--West Virginia University, 2001.
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Thesis (Ph. D.)--West Virginia University, 2006.
Title from document title page. Document formatted into pages; contains ix, 142 p. : ill. (some col.), col. maps. Includes abstract. Includes bibliographical references (p. 95-104).

Thesis (M.S.)--West Virginia University, 2003.
Title from document title page. Document formatted into pages; contains xii, 100, [15] p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 95-100).

Thesis (M.S.)--West Virginia University, 2005.
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Thesis (M.S.)--West Virginia University, 2006.
Title from document title page. Document formatted into pages; contains xiii, 85 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 82-84).

Thesis (M.S.)--West Virginia University, 2001.
Title from document title page. Document formatted into pages; contains xviii, 100 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 98-100).

Thesis (M.S.)--West Virginia University, 2003.
Title from document title page. Document formatted into pages; contains xii, 130 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 128-130).

Pour répondre à la fois aux nouvelles normes législatives et aux exigences du client, la complexité des camions s’est vue fortement augmentée au cours de ces dernières décennies. En plus de réduire les émissions de polluants, ces nouvelles normes imposent la mise en place d’un système de diagnostic des systèmes anti-pollution. Cela implique donc un contrôle plus fin ainsi qu’une surveillance accrue de ces dits systèmes. Le client quant à lui désire augmenter sa productivité et donc la disponibilité des camions. Afin de remplir ces exigences, le développement d’observateurs (ou capteur logiciel) représente une solution attractive. Ils permettent en effet d’obtenir plus d’informations à partir d’un nombre de capteurs donné, sans coûts supplémentaires pour le constructeur. Au cours de cette thèse, plusieurs observateurs ont été développés pour différents sous-systèmes du camion, dont des observateurs non-linéaires, LPV (Linéaire à Paramètres Variants), et avec retard. Dans un premier temps, dans le cadre de la surveillance et de la maintenance préventive, des observateurs ont été conçus dans le but d’estimer différents coefficients caractéristiques de la dégradation d’équipements tels que : un tendeur de courroie, le refroidisseur d'air de suralimentation et le refroidisseur des gaz d'échappement recirculés (EGR). Un observateur de la pression du collecteur d’échappement a également été développé dans le but de diagnostiquer un défaut du capteur mesurant cette pression. Dans un second temps, l’estimation du débit d’air massique EGR a été utilisée pour tester différentes méthodes d'observation sur banc d’essai, cette variable étant importante dans le contrôle des émissions de polluants. Enfin, dans une optique de réduction de coût, une estimation des débits d’air massiques entrant dans le moteur et celui de l’EGR a été réalisée sur la base d’un capteur soumis à un retard
To meet both new legislative standards and customer requirements, the complexity of trucks has increased significantly in the recent decades. In addition to reducing pollutant emissions, these new standards require on board diagnosis solutions for anti-pollution systems. Therefore it implies a thiner control and increased monitoring of these systems. Besides, the customer wants to increase productivity and therefore the availability of the truck. In order to fulfil these requirements, the development of observers (or virtual sensors) is an attractive solution. Indeed, more information can be obtained from a given number of sensors, without additional cost for the manufacturer. During this thesis, several observers were developed for different truck subsystems, including non-linear, LPV (Variable Parameter Linear) or delay observers. As a first step, from a monitoring and preventive maintenance point of view, observers have been designed to estimate different equipment degradation ratio such as: a belt tensioner, a charge air cooler and an exhaust gas recirculation (EGR) cooler. An observer of the exhaust manifold pressure has also been developed to diagnose a fault of the sensor measuring this pressure. In a second step, the EGR mass flow rate estimation was used to test different observation approaches on a test bench, this variable being important for the pollutant emissions control. Finally, in order to reduce cost, the observation of the inlet air and EGR mass flow rates has been studied with a sensor submitted to a delay

Thesis (M.S.)--West Virginia University, 2001.
Title from document title page. Document formatted into pages; contains xi, 88 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 84-85).

Diesel vehicles contribute substantially to statewide emissions of NOx, an ozone precursor, and to particulate matter. North Carolina Department of Transportation (NCDOT) is conducting a pilot study to demonstrate the use of B20 biodiesel fuel on approximately 1,000 vehicles in selected areas of the state; there are plans to extend the use of B20 fuel to a much larger number of vehicles in all 100 counties in North Carolina. Real-world in-use onroad and nonroad emissions of selected heavy-duty diesel vehicles, including those fueled with B20 biodiesel and petroleum diesel, were measured during normal duty cycles using a portable emissions measurement system (PEMS). Each vehicle was tested for one day on B20 biodiesel and for one day on petroleum diesel, for a total of 68 days of field measurements. The vehicles were operated by drivers assigned by NCDOT. Each test was conducted over the course of an entire workshift, and there were approximately 2 to 10 duty cycles per shift. Each duty cycle is comprised of a uniquely weighted combination of operating modes based on vehicle speed, acceleration, and typical modes of activities. Average emission rates on a mass per time basis varied substantially among the operating modes. Average fuel use and emissions rates increased 26 to 35 percent when vehicles were loaded versus unloaded. The use of B20 instead of petroleum diesel lead to a slight decrease (approximately 2 to 10 percent depending on the vehicle) in NO emission rate and significant decreases (approximately 10 to 30 percent depending on the vehicle) for opacity, HC, and CO, respectively. These trends are similar to nonroad vehicles. Factors that were responsible for the observed variability in fuel use and emissions include: operating mode, vehicle size, engine tier and size, vehicle weight, and fuel. In particular, emission rates were also found to decrease significantly when comparing newer, higher tier vehicles to older ones. Recommendations were made regarding operating strategies to reduce emissions, choice of fuel, and the need for future work to collect real-world duty cycle data for other vehicle types.

The controls for a parallel hybrid electric truck are optimized using numerical optimal control. Trade-offs between catalyst light-off times, NOx emission and fuel consumption have been investigated for cold starts at two operating points, as well as temperature differences between conventional and hybrid powertrains during WHTC (World Harmonized Transient Cycle). A model describing the temperature dynamics of the aftertreatment system is implemented as well as temperature-based deNOx performance for both Cu-Zeolite and Fe-Zeolite catalysts. Control is performed in a piecewise linear fashion, resulting in a total of 23 states including control signals. It is shown that high temperatures can be a larger threat to catalyst performance when running the WHTC than low temperatures, for both conventional and hybrid powertrains. Furthermore, decreasing the light-off time of the catalyst does not always lead to decreased NOx emission, instead there is a trade-off between light-off time and NOx emission. It is found that there are controls that will realize decreased NOx emission for a hybrid truck during cold starts at the expense of increased fuel consumption.

Air pollution is a threat to the environment and human health. Freight trucking in particular is the main source of freight transportation emissions. Heavy-duty trucks emit large amounts of toxic air pollutants that cause serious diseases and harm public health. In addition, heavy-duty trucks emit great amounts of greenhouse gas (GHG), which is the leading cause of global warming. Despite increased environmental restrictions on air pollution and rising trucking greenhouse gas emissions in the past decades, no economic study has examined the potential GHG and air pollution reductions in the trucking sector and the associated private abatement costs to the industry. This study accounts for GHG emissions and toxic air pollutants in measuring and evaluating efficiency and productivity for the trucking industry in the 48 contiguous states. Moreover, the private costs of abatement to the industry were also estimated. When only GHG was incorporated in the production model, the results showed that each state could expand desirable output and reduce GHG by an average of 11 percent per year between 2000 and 2007. The Malmquist-Luenberger productivity indexes showed that omitting or ignoring GHG in trucking service production yielded biased estimates. On the other hand, due to increased environmental regulations, most of the toxic air pollutants decreased dramatically between 2002 and 2005. The analytical results showed that inefficiency decreased during this period. The private costs of abatement averaged $73 million per state in 2005. When GHG and six toxic air pollutants were incorporated in the production model, the estimated private abatement cost was $76 million per state, which was equivalent to 0.7 percent of the industry output in 2005.

The transportation sector has a significant impact on the environment both nationally and globally since it is a major vehicle fuel consumption and emissions contributor. These emissions are considered a major environmental threat. Consequently, decision makers desperately need tools that can estimate vehicle emissions accurately to quantify the impact of transportation operational projects on the environment. Microscopic fuel consumption and emission models should be capable of computing vehicle emissions reliably to assist decision makers in developing emission mitigation strategies. However, the majority of current state-of-the-art models suffer from two major shortcomings, namely; they either produce a bang-bang control system because they use a linear fuel consumption versus power model or they cannot be calibrated using publicly available data and thus require expensive laboratory or field data collection. Consequently, this dissertation attempts to fill this gap in state-of-the-art emission modeling through a framework based on the Virginia Tech Comprehensive Power-Based Fuel consumption Model (VT-CPFM), which overcomes the above mentioned drawbacks. Specifically, VT-CPFM does not result in a bang-bang control and can be calibrated using publicly available vehicle and road pavement parameters. The main emphasis of this dissertation is to develop a simple and reliable emission model that is able to compute instantaneous emission rates of carbon monoxide (CO), hydrocarbons (HC) and nitrogen oxides (NOx) for the light-duty vehicles (LDVs) and heavy-duty diesel trucks (HDDTs). The proposed extension is entitled Virginia Tech Comprehensive Power-Based Fuel consumption and Emission Model (VT-CPFEM). The study proposes two square root models where the first model structure is a cubic polynomial function that depends on fuel estimates derived solely from VT-CPFM fuel estimates, which enhances the simplicity of the model. The second modeling framework combines the cubic function of the VT-CPFM fuel estimates with a linear speed term. The additional speed term improves the accuracy of the model and can be used as a reference for the driving condition of the vehicle. Moreover, the model is tested and compared with existing models to demonstrate the robustness of the model. Furthermore, the performance of the model was further investigated by applying the model on driving cycles based on real-world driving conditions. The results demonstrate the efficacy of the model in replicating empirical observations reliably and simply with only two parameters.
Ph. D.

Ballast som byggnadsmaterial är viktigt för att utveckla vårt samhälle då det bland annat används som beståndsdel i asfalt och betong. Det är därför viktigt att bergkross som bryts i bergtäkter har en fungerande produktion för att möta efterfrågan men också för att Sverige ska kunna nå målet att vara klimatneutralt 2045. Syftet med arbetet är att minska miljöpåverkan i en bergtäkt från de interna transporterna och målet är att ta fram åtgärder för att uppnå detta. De metoder som har använts är litteraturstudier, beräkningar, simuleringar och intervjuer. Genom beräkningarna kunde ett resultat i detta arbete visa att en reducering med 88 % av koldioxidutsläpp kan göras genom att använda biodrivmedlet HVO Diesel 100. Det har med hjälp av intervjuer och litteraturstudier dessutom dragits en slutsats att framtidens bergtäkter antas producera bergkross med elektriska autonoma maskiner.
Ballast as a building material is important for developing our society as it’s used as a component in asphalt and concrete. Hence it is important that crushed rock extracted from a quarry have a functioning production to meet the demand that exists, but also because Sweden should be able to reach the goal of being climate neutral 2045. The purpose of this study is to reduce the environmental impact in a quarry from the internal transports and the aim is to bring out suggestions to achieve this. The methods that have been used are literature studies, calculations, simulations and interviews. Through the calculations, a result in this work showed that a reduction of 88 % of carbon dioxide emissions can be made by using the biofuel HVO Diesel 100. In addition, with the help of interviews and literature studies, conclusions have been drawn that the future quarries are believed to produce crushed rock with electric autonomous machines.

L'augmentation du prix du pétrole ainsi qu'une possible future réglementation des émissions de CO2 encourage les fabricants de véhicules industriels à trouver de nouvelles solutions pour améliorer encore la performance de la chaine cinématique. Dans ce cadre, deux solutions de récupérations d'énergie prometteuses sont très souvent rapportées dans la littérature: le système de récupération d'énergie par cycle de Rankine et le générateur thermoélectrique. Après un rappel des conditions limites du fonctionnement d'un camion long routier, cette thèse démontre tout d’abord la modélisation 0-D et 1-D (logiciels commerciaux utilisés) de ces deux systèmes de récupération d’énergie. Pour le générateur thermoélectrique, des études paramétriques (hauteur de jambe thermoélectrique, prix, puissance électrique produite) sont effectuées se basant principalement sur l'utilisation de deux matériaux prometteurs. Une conception du système Rankine est présentée et modélisée avec le solveur 1-D. Des validations partielles sont réalisées sur les composants (turbine). Ce modèle a ensuite permis d'étudier les transitoires du système ainsi que la charge en réfrigérant et un système de contrôle possible. Cette étude montre que le générateur thermoélectrique n’est pas encore mature pour son utilisation dans un camion long routier. Le système Rankine doit quant à lui être testé sur un camion prototype pour pouvoir véritablement estimer son potentiel final
Fuel price increase as well as future fuel consumption regulations lead truck manufacturers to further enhance the current powertrain. In such a context, two waste heat recovery technologies appear as promising: the Rankine system as well as the thermoelectric generator. After a reminding of truck boundary conditions, this thesis work defines 0-D and 1-D modeling (commercial tool used) for both systems.For the thermoelectric generator , parametric 1-D studies are done on the integration/design (number of thermoelements, price, electrical power) of a thermoelecric generator upstream the existing engine exhaust gas recirculation cooler. Main studies are done with thermoelectric materials but other materials are also considered. A Rankine system design is presented and modeled under a 1-D solver. Preliminary validations are presented. Transient aspects are evaluated to better understand the behavior of the system and its bottlenecks. The amount of refrigerant in the circuit and the control schematic are also addressed.From these studies, it appears that the thermoelectric generator technology is not yet mature for a long haul truck due to the low performance of thermoelectric materials. The Rankine system technology should handle a complete truck prototype testing to estimate its potential

This master work deals with different fuels for trucks Scania and it is divided into theoretical and practical parts. The theoretical part describes the basic concepts related to the topic. The most important are associated with transport and transportation, categorization and types of vehicles, greening road transport or financing. Depending on the practical part it is also place great emphasis on selected types of fuels, their production and also their advantages and disadvantages. In the practical part is introduced Scania company and the products and services that the company offers. Furthermore, this section generally analyzes Scania offer of engines for different types of fuels, including technical recommendations. At the end of the practical part are described specific vehicles, which are compared from financial aspect, in terms of environmental impact and operational limitations. The aim of the study is to compare Scania trucks using diesel, biodiesel and CNG.

Due to increased demands on fuel economy the question of a more intelligent engine control for driving a truck-mounted crane has been raised. The aim of this thesis is to develop a new engine control for crane driving. The primary concern for the new engine control is fuel economy, but other factors, such as driver environment and drivability, have been taken into consideration as well. A literature study investigating engine control in construction machines has also been carried out and the results are presented in this report. Due to the fact that the hydraulic control system as well as the diesel engine control system is designed by the same construction machine manufacturer, more complex control strategies are utilized in these applications. In order to test the new control strategy a full-scale test has been carried out on a Scania truck with a crane from Hiab. The results point towards lower fuel consumption, better driver experience and lower noise levels. Some of the control features of the new control are suggested to be placed in the crane, and some in the truck. Only a small expansion of the communication between truck and crane would be necessary in order for the new control strategy to work. The experiences from the literature study point on several features utilized in construction machines that could be implemented in the crane control of the future.
På grund av ökade krav på minskad bränsleförbrukning har frågan om en förbättrad motorstyrning vid krankörning av lastbilsmonterade kranar blivit aktuell. Målet för detta examensarbete är att utveckla en ny motorstyrning anpassad för krankörning. I första hand syftar den nya motorstyrningen till att minska bränsleförbrukningen, men även andra faktorer såsom förarmiljö och körbarhet har tagits hänsyn till. En litteraturstudie om motorstyrning i hydrauliska grävmaskiner och andra hydrauliska maskiner har också utförts och resultatet finns presenterat i denna rapport. Eftersom det hydrauliska styrsystemet såväl som dieselmotorstyrsystemet är sammansatt hos en och samma tillverkare används mer komplicerade styralgoritmer i dessa tillämpningar. För att testa den nyutvecklade motorstyrningen har fullskaletest utförts på en Scanialastbil utrustad med en kran från Hiab. Resultaten pekar på lägre bränsleförbrukning, bättre förarupplevelse och lägre ljudnivå. Somliga av funktionerna i den nya styrningen föreslås placeras i lastbilen och andra i kranen. Bara en mycket liten utvidgning av kommunikationen mellan kran och lastbil skulle behövas för att denna styralgoritm skulle fungera. Lärdomarna ifrån litteraturstudien visar på att flera av de styrfunktioner som används ibland annat grävskopor skulle kunna komma till nytta i motor- och kran styrningen i en lastbilsmonterad kran i framtiden.

Heavy-duty trucks accounts for 25% CO2 emissions in Sweden and there is approximately 12.6 million heavy-duty vehicles in the EU with different types of fuel and utilization areas. EU is implementing increased legislations to reduce emissions and increase the use of biofuel and members of the EU is starting to ban the use of diesel trucks in local areas, which drives the need to find other suitable fuel. Therefore, to study and compare the emissions and energy demand in the heavy-duty truck industry a case study is created. Which focuses on production and processing, transportation, distribution and fuel consumption. Cultivation of maize and anaerobic digestion of maize, waste and manure is included as well. Data gathered from the collaboration between the European Commission’s Joint Research Centre, eucar and Concawe (JEC) is used to create scenarios and these are validated with previous studies. The case study includes seven LNG cases, three LBG cases and two diesel cases together with several other cases collected for verification. Furthermore, potential boil-off and leakage during maintenance is included to further estimate the possible emissions correlated with LNG and LBG vehicles. The Well-to-Wheels analysis resulted in most LNG and LBG cases having higher energy input compared to diesel. LBG has the lowest emissions of greenhouse gases. The transportation method and distance are the most important aspects for the Well-to-Tank analysis. The fuel consumption is the main source of emissions and energy input in the Tankto-Wheels analysis. In conclusion, the transportation and fuel consumption are the greatest contributors of emissions and energy demand in the complete Well-to-Wheels analysis.

The construction industry is facing a reality where the dependency on fossil fuels needs to cease and be replaced by options that are more climate friendly. One such option is the electrification that has not made a breakthrough in the construction industry yet and therefore needs to be examined. In this thesis an investigation is made by two different systems of wheel loaders and trucks. One system that conducts machines run by electricity and another one where the system is powered by diesel. The investigation is based on goal formulation which serves as the basis for answering these questions. The machines were examined in such as to obtain results that illustrate which system of machines that are profitable with regards to time, energy consumption, carbon dioxide emissions and total costs. This thesis has also as an intent to identify any advantages and disadvantages of each transport method. This is done in order to lend structure to any further research conducted in the future. To be able to compare and examine the properties of the machines, these machines were applied to a tunneling project. The project that was received was the metro station Hagalunds industriområde. The planned expansion of the subway will lead to a new metro line between Arenastaden and Odenplan, where Hagalunds industriområde will become an intermediate station. In order to truly optimize our efforts and carry out the calculations, the focus was placed on a partial stretch of 1 000 meters with respect to the main tunnel and working tunnel. The result obtained shows that the electric wheel loader leads to less time, carbon dioxide emissions and better energy efficiency than the diesel-powered wheel loader. On the other hand, the disadvantage is that the purchase cost of the electric wheel loader leads to greater total costs. These investments may be necessary to break the dependence on fossil fuels. When comparing the trucks, the result showed that the electric truck is a better alternative from an environmental perspective and total costs. While the diesel-powered truck saves on both time and energy. The reason why the total cost of the diesel-powered truck differs greatly from the electricpowered truck is the rental costs. If the diesel-powered truck was instead purchased, the total cost difference could be reduced.
Bygg- och anläggningssektorn står inför en verklighet där beroendet av fossila bränslen behöver brytas och ersättas med miljövänligare alternativ. Ett sådant alternativ är elektrifieringen som inte riktigt har slagit igenom för anläggningssektorn och därför behöver undersökas. I detta examensarbete undersöks två olika system av hjullastare och lastbilar. Ett system där maskinerna drivs med el och ett annat system med maskiner som drivs på diesel. Undersökningen hade målformuleringen som utgångspunkt för att besvara frågeställningarna. Maskinerna granskades för att erhålla ett resultat som visar vilket system av maskiner som är lönsammare att använda med avseende på tidsåtgång, energiförbrukning, koldioxidutsläpp samt totala kostnader. Examensarbetet har även som syfte att redogöra eventuella för-och nackdelar för respektive transportmetod. Detta för att ge ytterligare underlag till vidare forskning. För att kunna jämföra och undersöka maskinernas egenskaper applicerades dessa maskiner på ett tunneldrivningsprojekt. Projektet som erhölls var tunnelbanestationen Hagalunds industriområde. Den planerade utbyggnaden av tunnelbanan kommer att leda till en ny tunnelbanelinje mellan Arenastaden och Odenplan, där Hagalunds industriområde kommer bli en mellanliggande station. För att avgränsa arbetet och genomföra beräkningarna lades fokus på en delsträcka om 1 000 meter med avseende på huvudtunnel och arbetstunnel. Resultatet som erhölls visar att den eldrivna hjullastaren leder till mindre tidsåtgång, koldioxidutsläpp och bättre energieffektivitet än den dieseldrivna hjullastaren. Däremot är nackdelen att inköpskostnaden för den eldrivna hjullastaren leder till större totala kostnader. Dessa investeringar kan vara nödvändiga att vidta för att beroendet av fossila bränslen ska brytas. Vid jämförelse av lastbilarna visade resultatet att den eldrivna lastbilen är ett bättre alternativ ur miljöperspektiv och totala kostnader. Medan den dieseldrivna lastbilen sparar på både tid och energi. Anledningen till att totala kostnaden för dieseldrivna lastbilen skiljer sig mycket från den eldrivna lastbilen är hyreskostnaderna. Om den dieseldrivna lastbilen istället köptes in, kunde den totala kostnadsskillnaden reduceras.

This thesis deals with braking effect of the truck’s engine. The theoretical part introduces the reader to the basic construction of trucks, describes most using engine and defines the factors having a significant effect on engine braking. In the practical part the reader is familiar with the technique used in making the measurement and description of the vehicle chosen for the implementation of measurement. The result of the practical part is the values obtained by measurement including their interpretation contained in the conclusion.

Syftet med examensarbetet var att översiktligt undersöka vilka hälsofarliga luftföroreningarsom medarbetarna vid hamnmagasinen eventuellt exponeras föroch huruvida något hygieniskt gränsvärde riskerade att överskridas samt att seom de skyddsåtgärder som vidtagits kan förbättras. Resultatet från studien visaratt det finns vissa exponeringsrisker för de som arbetar vid hamnen både frångods, dieselavgaser samt rester av gasbehandlingsmedel i containrar.Arbetsmomenten där truckföraren befinner sig inne i trucken bedöms somrelativt skyddat både från partiklar och gaser, men det finns andra arbetsuppgifterdär arbetaren inte är lika skyddad. Mätningarna av kvävedioxid visadeatt exponeringen av dieselavgaser för den medarbetare som öppnadecontainrarna inte översteg några hygieniska gränsvärden, under de dagar sommätningarna genomfördes, men var något högre än för truckföraren som satt ihytten. Huruvida exponeringen av damm från gods riskerar att utvecklas tillhälsoproblem är omöjligt att avgöra utan en grundlig riskbedömning, därdammätningar kan ge en fingervisning om hur riskfylld situationen är för desom eventuellt exponeras.Organisationen bör implementera säkrare rutiner och genomföra åtgärder sommotiverar medarbetarna att använda befintlig skyddsutrustning. Det gäller intebara för exponering av dieselavgaser och damm från lossning och lastning avgods utan även vid öppnandet av containrar där rester av gasbehandlingsmedelkan finnas kvar i containern och där några ämnen misstänkts varacancerframkallande.Slutsatser: Genomföra en grundlig riskbedömning och kartlägga möjliga hälsoriskerkring luftföroreningar. Upprätta skriftliga arbetsbeskrivningar där eventuella risker föreligger. Installera ventilation i magasinen som styrs av halten kvävedioxid för attsäkerställa att höga halter av dieselavgaser inte uppstår. Behov av motivationshöjande insatser kring säkerhetskultur ochanvändningen av skyddsutrustning. Implementera fungerande rutiner som följer lagstiftningen förhanteringen av damm och gaser som gäller för cancerframkallandeämnen.
The purpose of this thesis was to examine the risk of hazardous air pollutantsthat employees at the harbor may be exposed to and assess whether anyexposure limits might be exceeded, and to review if the security measures taken,can be improved. The results of the study show that there is some risk ofexposure for those working in the harbor from both the cargo, diesel exhaustand residues from fumigants in the containers. The operations when the truckdriver is inside the forklift is considered relatively protected from both particlesand gases, but there are other tasks where the worker is not as protected.Measurements of nitrogen dioxide showed that exposure to diesel exhaust forthe employee who opened the containers during the days that the measurementswere performed did not exceed some critical values, but was slightly higherthan for the driver who was sitting in the forklift. Whether the exposure to dust,from the cargo, constitutes a risk for health effects is impossible to determinewithout a thorough risk assessment, where measurements of dust can give anindication of how risky the situation is for the exposed workers.The organization should implement safer practices and implementing measuresthat motivates employees to use existing protective equipment. This applies notonly for exposure to diesel exhaust and dust from loading and unloading ofgoods, but also at the opening the doors on the containers in which residues offumigants, in which some are suspected to be carcinogenic, can remain in thecontainer.Conclusions: Conduct a thorough risk assessment and identify potential health riskswith air pollution. Establish written work instructions where potential hazards exist. Install ventilation in the warehouses, which is controlled by the levels ofnitrogen dioxide, to ensure that high levels of diesel exhaust does notoccur. Need to increase motivation for safety and the use of protectiveequipment. Implement procedures to comply with the legislation for the managementof dust and gases that applies to carcinogens substances.

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Funda??o de Amparo ? Pesquisa do Estado do Rio Grande do Sul (FAPERGS)
The transport sector represents a significant responsibility in the pollution emissions. Also, the consumption of fossil fuels is related with the rising of global average temperature due to the greenhouse gas emissions. Biofuels and natural gas are investigated as alternative fuels to mitigate the environmental impacts. However, due to the several source emissions within a product life-cycle, the environmental performance of an environmental friendly product must be verified. This work aims to quantify greenhouse gas emissions during household waste collection by heavy vehicles (trucks) fueled with different fuels. It was proposed the development and implementation of a methodology to compare both pollutant gas emissions and noise for the use of CNG (compressed natural gas) and diesel-B5, aiming to mitigate environmental impacts in captive fleet that travels daily in the Porto Alegre city, Rio Grande do Sul state, Brazil. The trucks were monitored using a portable gas analyzer equipment (O2, CO, CO2, NO, NO2, NOx, SO2, HC), and the fuel consumptions and autonomy were obtained from the company that provides the service. With the data collected on established routes, it was applied the Life Cycle Assessment (LCA) methodology to carry out the study comparing the environmental performance of the use of CNG and Diesel-B5. The results showed that higher global warming impact (according IPCC method) was observed to CNG, independently of the time horizon considered (20 100 or 500 years). When comparing the contribution of the process stages (from production to use of fuels), CNG presented higher impacts in the collection and venting steps, while diesel -- B5 presented in the collection step.
O setor de transportes apresenta significativos problemas ambientais relacionados ?s emiss?es de poluentes, agravados em regi?es urbanas. A queima e a explora??o de combust?veis f?sseis s?o constantemente relacionadas ao aumento da temperatura m?dia global. O uso de combust?veis, como os de origem vegetal e g?s natural, tem sido uma alternativa frequente na mitiga??o de gases de efeito estufa. No entanto, devido ?s v?rias fontes de poluentes presentes no ciclo de vida do produto, o desempenho ambiental de produtos considerados amig?veis ao meio ambiente deve ser verificado. Este trabalho teve como objetivo quantificar as emiss?es de gases de efeito estufa emitidos durante a coleta de res?duos domiciliares por ve?culos pesados (caminh?es) abastecidos com diferentes combust?veis: g?s natural e diesel-B5. Prop?e-se o desenvolvimento e a implementa??o de uma metodologia para a compara??o das emiss?es de poluentes para o uso de GNV (g?s natural veicular) e Diesel-B5, objetivando a mitiga??o de impactos ambientais em frota cativa que trafega diariamente na cidade de Porto Alegre ? RS. Os caminh?es foram monitorados com um equipamento analisador port?til de gases (O2, CO, CO2, NO, NO2, NOx, SO2, HC), e os consumos e a autonomia dos combust?veis foram obtidos junto ? empresa prestadora do servi?o. Com os dados levantados nas rotas estabelecidas, foi aplicada a metodologia de Avalia??o do Ciclo de Vida (ACV) para realizar o estudo de compara??o do desempenho ambiental entre o uso de GNV e Diesel-B5, considerando todas as etapas desde a produ??o at? o consumo final dos combust?veis. Os resultados mostraram que o maior potencial para aquecimento global (segundo o m?todo IPCC) ocorre para o GNV, considerando per?odos de 20 anos, 100 anos e 500 anos. Quando comparadas as contribui??es das diferentes etapas do processo, desde a produ??o at? o uso do combust?vel, observou-se que o GNV apresenta os maiores impactos nas etapas de transporte e coleta de res?duos, enquanto o Diesel-B5 apresenta impacto significativo apenas na etapa de coleta de res?duos.

The topic of the thesis is costs in truck transport. There is analyzed theme Progress of costs in time, using indexes. The theoretical part is focused on the methodology for calculating the cost index published by the Czech Association of Road Carriers Česmad Bohemia and compared with several foreign indexes. The practical part has two objectives. The first focuses on the design of a new methodology that will be more accurate and reflect the true situation. The second objective of this methodology is to design basic informatics support, for both users, indexes users and persons, who are responsible for publishing these statistics. The summary points to the possibilities of alteration of the current designed index methodology and the potential for cooperation of Česmad Bohemia and Czech Statistical Office.

Die Entwicklung schwerer Nutzfahrzeugmotoren unterliegt dem Zielkonflikt zwischen möglichst geringen Betriebskosten, hoher Leistung und der Einhaltung von Emissionsvorschriften. Bezüglich der Auslegung der Verdichterstufe des Abgasturboladers resultiert dies in einem Kompromiss zwischen Kennfeldbreite und den Wirkungsgraden im Nennpunkt sowie im Hauptfahrbereich. In der vorliegenden wissenschaftlichen Publikation wird untersucht, ob mit Hilfe einer geometrischen Verstellbarkeit des Verdichters eine bessere Lösung für das anspruchsvolle Anforderungsprofil gefunden werden kann. Das Ziel ist eine Reduktion des Kraftstoffverbrauchs eines 12,8l NFZ-Dieselmotors im schweren Fernverkehr, ohne dass hierbei Abstriche bezüglich weiterer Leistungsmerkmale der Verdichterstufe in Kauf genommen werden müssen. In einem ersten Schritt wird hierzu mit Hilfe der Auswertung von Lastkollektivdaten der für den Kraftstoffverbrauch relevante Betriebsbereich der Basis-Verdichterstufe identifiziert. Dieser befindet sich bei vergleichsweise geringen Massenströmen und hohen Totaldruckverhältnissen in der Nähe der Volllast-Schlucklinie im Verdichterkennfeld. Die Auswertung von ein- und dreidimensionalen Strömungssimulationen führt zur Erkenntnis, dass die hohen Tangentialgeschwindigkeiten im unbeschaufelten Diffusor ausschlagge- bend sind für die Strömungsverluste innerhalb der Verdichterstufe im Hauptfahrbereich. Eine Möglichkeit die Geschwindigkeitskomponente in Umfangsrichtung zu reduzieren, ist die Verwendung eines beschaufelten Diffusors. Zur Überprüfung des Potentials werden im Rahmen einer Parameterstudie 47 unterschiedliche Nachleitgitter im Diffusor der Basis-Verdichterstufe am Heißgasprüfstand untersucht. Es stellt sich heraus, dass durch den Einsatz einer Nachleitbeschaufelung der Verdichterwirkungsgrad um bis zu 8 Prozentpunkte verbessert werden kann, die Kennfeldbreite jedoch nicht ausreicht, um die motorischen Anforderungen bezüglich der Pumpstabilität oder der Bremsleistung zu erfüllen. Resultierend aus diesen Erkenntnissen werden drei variable Verdichter entwickelt, mit dem Ziel, den Wirkungsgradvorteil beschaufelter Diffusoren mittels einer geometrischen Verstellbarkeit für den schweren Nutzfahrzeugmotor nutzbar zu machen. Die Bewertung hinsichtlich der Ziele und Anforderungen erfolgt anhand von Versuchen am Heißgas- sowie Vollmotorenprüfstand. Die Variabilität mit der geringsten Komplexität ist die Kombination aus starrem Nachleitgitter und Schubumluftventil. Das System zeichnet sich dadurch aus, dass Strömungsabrisse im Bereich des Nachleitgitters durch Aktivieren des Schubumluftventils und somit Öffnen eines Rezirkulationskanals im Verdichtergehäuse in pumpkritischen Situationen vermieden werden können. Der Verzicht auf bewegliche Teile im Diffusor resultiert in der höchsten Reduktion des Kraftstoffverbrauchs um 0,6 − 1,4% im Hauptfahrbereich. Der Doppeldiffusor besitzt zwei separate Strömungskanäle unterschiedlicher Geometrie, die im Betrieb durch eine axiale Verschiebung mit Druckluft aktiviert werden können. Dieses völlig neuartige Konzept ermöglicht es, die Auslegungsziele auf zwei Diffusoren aufzuteilen und somit für jede Kennfeldhälfte die jeweils optimale Schaufelgeometrie auszuwählen. Mit dieser Variabilität kann die Einspritzmenge im Hauptfahrbereich um 0,5 − 0,8 Prozent gesenkt werden. Das System mit der höchsten Komplexität ist der Verdichter mit rotierbarer Nachleitbeschaufelung. Über einen elektronischen Steller können die Anstellwinkel und Halsquerschnitte in jedem Betriebspunkt den Anströmbedingungen angepasst werden, um den jeweils bestmöglichen Wirkungsgrad zu erhalten. Aufgrund der anspruchsvollen geometrischen Zwangsbedingungen bei der Auswahl der Schaufelgeometrie besitzt der Dreh- schaufler mit 0,3−0,6% das geringste Potential zur Verbesserung der Kraftstoffsparsamkeit, erzielt jedoch das beste Ergebnis bezüglich der Bremsleistung und der Pumpstabilität
Reducing the total costs of ownership, achieving the rated engine power and compliance with exhaust-emission legislation are competing goals regarding the development of heavy duty engines. This leads to demanding requirements for the aerodynamic design of the turbocharger compressor stage such as high efficiencies at various operating points and a broad map width. The aim of the present doctoral thesis is to investigate the potential of a compressor with variable geometry in order to obtain a better compromise between efficiency and compressor map width for the purpose of increasing fuel economy without sacrifices concerning the rated power, engine brake performance or surge stability. In a first step, the evaluation of load cycles yields operating points on which the fuel consumption is heavily dependent. Results of 1D- and 3D fluid flow simulations show that the high tangential velocity in the vaneless diffusor is the main cause for the reduction of compressor efficiency in the main driving range. A parameter study containing 47 different geometries is conducted at a hot gas test rig in order to examine the potential of vaned diffusers regarding the reduction of the tangential velocity component. It can be seen that by introducing diffuser vanes compressor efficiency can be increased by up to 8 percent. The narrow map width however prevents the use of a fixed geometry for heavy duty engines. Based on those results three variable geometry compressors are developed with the goal of maintaining the efficiency benefit of vaned diffusers while increasing the map width by adjustable geometric features. The evaluation of the variable compressor systems is based on hot gas and engine test bench measurements. The variable compressor system with the lowest complexity utilizes a recirculation valve in the compressor housing in combination with a fixed geometry vaned diffuser in order to improve the surge margin for a short period of time at a sudden load drop. The abandonment of functional gaps in the diffuser leads to the highest improvement of fuel economy of 0,6 − 1,4% in the main driving range. The compressor with stacked diffuser vanes has two separate flow channels in the diffuser. During engine operation only one vaned diffuser geometry is active. The axial movement is performed via pressure chambers in the compressor and bearing housing. The two diffuser geometries are either optimized for high or low mass flows. This way the fuel consumption in the main driving range can be reduced by 0,5 − 0,8%. The compressor with pivoting vanes in the diffuser has the highest complexity of all systems. With the aid of an electronic actuator the vane inlet angle and throat area can be adjusted to the impeller outlet flow conditions at each operating point. As a consequence the pivoting vanes compressor achieves the best results regarding engine brake performance and surge stability. The fuel economy in the main driving range can be improved by 0,3 − 0,6%. Higher benefits are prevented by demanding geometric constraints in order to ensure the rotatability of the vanes and to prevent vibrations of the impeller blades

Thesis (Ph. D.) -- University of Tennessee, Knoxville, 2005.
Title from title page screen (viewed on June 28, 2005). Thesis advisor: Terry L. Miller. Document formatted into pages (xii, 467 p. ; ill. (some col.), maps). Vita. Includes bibliographical references (p. 118-122).

碩士
嘉南藥理大學
環境工程與科學系
107
In this study, the active regenerative Diesel particulate filter (DPF) was installed on 50 diesel garbage trucks to discuss the effect of DPF on the reduction of air pollutants emitted by diesel vehicles. Observed from 2015 to 2018, the opacity of the test vehicle before and after the installation of the filter was measured, and based on the opacity rate, 10 measurements were taken after the regular time after the installation of the DPF. Understand the situation after using the filter for a long time and reusing it. The research results show that before the installation of the DPF, there are 28 exhaust emission opacity of more than 1.2 in 50 diesel vehicles, the failure rate is 72%, and the opacity is effectively reduced after installing the DPF. The total number of effective detections of 50 times, the total number of opacity is 0, up to 49 times, the ratio of opacity to 0 is as high as 98.3%, and the opacity is not 0, only 1 time. The ratio of opacity to non-zero is only 1.7%, and only one of the vehicles in the ninth test has an opacity exceeding the emission standard of opacity of 0.6. The cause is the filter. Damaged or not developed due to regular maintenance, and other vehicles did not have this problem, indicating that DPF installation and long-term regeneration use has the effect of reducing particulate pollutants.

Documentos apresentados no âmbito do reconhecimento de graus e diplomas estrangeiros
Climate change due to greenhouse gas emissions led to new vehicle emissions standards which in turn led to a call for vehicle technologies to meet these standards. Modeling of vehicle fuel consumption and emissions emerged as an effective tool to help developing and assessing such technologies. Although vehicle analytical models are favourable in many cases due to describing the physical phenomena associated with vehicle operation based on the principles of physics and with explainable mathematical trends and with extendable modeling to other vehicle types, no analytical model has been developed and experimentally validated as yet of diesel fuel consumption and exhaust emissions rate. The present study analytically models diesel fuel consumption rate microscopically for the accelerating, cruising and decelerating modes of driving a vehicle and models diesel regulated emissions rate for the cruising mode of driving a vehicle. In order to make these models, an analytical model of the following subsystems has been made: (i) intake manifold taking the flexibility of crankshaft and air density into account, (ii) supercharging diesel centrifugal compressor, (iii) multi-cylinder supercharged diesel engine, (iv) diesel fuel system and engine power, (vi) exhaust system and the percentage of unburned fuel. Sensitivity analysis has been conducted for simplifying the models in order to fit the INTEGRATION software and traffic simulator. The models have been validated experimentally against field data. For the rate of diesel fuel mass flow, the average percentage of deviation was 1.8% for all standard cycles outperforming widely recognized models such as the CMEM and VT-Micro. The simulated results have been analyzed statistically for the rate of diesel fuel mass flow with coefficient of determination and relative error of 96% and 1.2%, respectively. The average percentage of deviation of 7% 1.7%, 1.9%, 2%, and 10.6% for the diesel engine power, CO emission, NOx emission, HC emission, and percentage of unburned fuel respectively, for all Freeway cycles outperforming widely recognized models such as the CMEM and VTMicro. The simulated results have been analyzed statistically as well with coefficient of determination of 73%, 99%, 99%, 83%, and 70% respectively. The corresponding relative error has been 7%, 3%, 1.7%, 2%, and 10.6% respectively. Moreover, the developed analytical models of the intake manifold gas speed dynamics, in-cylinder gas speed dynamics, supercharging compressor power, supercharging compressor mechanical efficiency, and supercharged air density have been experimentally validated using case studies with an average of deviation from field data of 12.6%, 11%, 3%, 8%, and 3.7%, respectively. The simulated results have been analyzed statistically as well with relative error of 12.6%, 11%, 3%, 8%, and 3.7%, respectively. In addition to devising two new classifications, which are the formulation approach-based modelling and main input variable-based modelling, the models developed in this study are (a) widely valid models which are not restricted to a specific dataset, (b) an effective tool to quickly judge whether the related experimental measurements make sense or not, (c) show which chemical reaction within the powertrain kinetically influences significantly emissions rate.

碩士
輔英科技大學
環境工程與科學系碩士班
106
The International Agency for Research on Cancer (IARC) of the World Health Organization (World Health Organization, WHO) issued an amendment to the emission of particulate matter pollution (black smoke) from diesel vehicles from suspected carcinogens to affirmative carcinogens in June 2012. It has been identified as Category 1 carcinogens so it is necessary to regulate the emissions of diesel vehicles. Kaohsiung is a smart city with a booming economy in Taiwan. Kaohsiung Port is also an important port area for import and export. According to the research data of the 2010 China Technical Journal - Kaohsiung Port Container Terminals, the total number of vehicles entering and leaving the port area was about 122,000 vehicles, and about 77,000 vehicles on holidays. Among them, the estimated number of diesel vehicles such as large trucks and connected vehicles accounted for approximately 28.1%. The air pollution discharge of Kaohsiung Port is the highest of the five major commercial ports in Taiwan. The annual emissions of NOX (nitrogen oxides) and SOX (sulfur oxides) exceed 10,000 tons. According to the statistics of the Ministry of Communications, there are about 30,000 large-scale diesel vehicles in Kaohsiung City, which is the largest in this country. About 25,000 diesel vehicles enter and exit the Kaohsiung Port area from other cities and counties every day, resulting in PM2.5 accounting for approximately 10% in Kaohsiung City. This study is mainly based on the diesel vehicles carrying cargoes in the Kaohsiung Port area. The purpose of the study is to examine the effectiveness of diesel vehicle inspections in Kaohsiung Port Area, and to understand the average degree of pollution, vehicle type distribution of diesel vehicles operated in Kaohsiung Port Area and the effectiveness of the inspection and control of diesel vehicles in Kaohsiung Port Area. This study combines the independent management of diesel vehicles, the license plate identification system, the visual inspection of motor vehicles and the roadside interception operations to collect data for further analysis. The diesel engine exhaust smoke detection results serve as evidence for the improvement of pollution control. In addition, the distribution of large-scale diesel vehicles got in and out the Kaohsiung Harbor District before and after the announcement to designate the “Low-contamination Carrier Demonstration Operating Area” was also discussed. As a result, it was found that the number of self-management of diesel vehicles had increased by at least 2 times compared with previous years; the compliance ratio of self-management A1-A3 raised from 6.2% before the announcement of the “Low-Contaminated Vehicle Demonstration Operation Zone” to 16.6%. The average emission level of diesel vehicle emissions dropped from 34.9% in 2011 to 26.7% in 2014. The average light absorption coefficient decreased from 1.32 m-1 in 2015 to 1.15 m-1 in 2017. The ratio of unqualified diesel vehicles was 27.9% in 2011, it had dropped to 12.4% in 2017. In addition, the pollution control of each container center was explored. The average emission level decreased from 39.3% to 27.5% in the third container center, and the average light absorption coefficient decreased from 1.60 m-1 to 0.99 m-1 in the sixth container center. According to the roadside interception data of diesel vehicles, the ratio of vehicles belonged to Phase 1 ~ Phase 3 had dropped from 86.5% in 2016 to 82.5% in 2017. The ratio of vehicles belonged to Phase 4 and Phase 5 had increased from 13.5% in 2016 to 17.5% in 2017. According to the information obtained from license plate identification system, the proportion of vehicles belonged to Phase 1 ~ Phase 3 dropped from 60.2% in 2016 to 55.0% in 2017. The proportion of vehicles belonged to Phase 4 and Phase 5 increased from 39.8% in 2016 to 45.0% in 2017. The proportion of old vehicles declined. In contrast, the ratio of new vehicles increased slightly. It is suggested that government should step up propaganda and promotion of "low-pollution vehicle demonstration operation areas" and extend the control experience of Kaohsiung Port Area to other ports. And making high-pollution diesel vehicles gradually disappear.

Die Entwicklung schwerer Nutzfahrzeugmotoren unterliegt dem Zielkonflikt zwischen möglichst geringen Betriebskosten, hoher Leistung und der Einhaltung von Emissionsvorschriften. Bezüglich der Auslegung der Verdichterstufe des Abgasturboladers resultiert dies in einem Kompromiss zwischen Kennfeldbreite und den Wirkungsgraden im Nennpunkt sowie im Hauptfahrbereich. In der vorliegenden wissenschaftlichen Publikation wird untersucht, ob mit Hilfe einer geometrischen Verstellbarkeit des Verdichters eine bessere Lösung für das anspruchsvolle Anforderungsprofil gefunden werden kann. Das Ziel ist eine Reduktion des Kraftstoffverbrauchs eines 12,8l NFZ-Dieselmotors im schweren Fernverkehr, ohne dass hierbei Abstriche bezüglich weiterer Leistungsmerkmale der Verdichterstufe in Kauf genommen werden müssen. In einem ersten Schritt wird hierzu mit Hilfe der Auswertung von Lastkollektivdaten der für den Kraftstoffverbrauch relevante Betriebsbereich der Basis-Verdichterstufe identifiziert. Dieser befindet sich bei vergleichsweise geringen Massenströmen und hohen Totaldruckverhältnissen in der Nähe der Volllast-Schlucklinie im Verdichterkennfeld. Die Auswertung von ein- und dreidimensionalen Strömungssimulationen führt zur Erkenntnis, dass die hohen Tangentialgeschwindigkeiten im unbeschaufelten Diffusor ausschlagge- bend sind für die Strömungsverluste innerhalb der Verdichterstufe im Hauptfahrbereich. Eine Möglichkeit die Geschwindigkeitskomponente in Umfangsrichtung zu reduzieren, ist die Verwendung eines beschaufelten Diffusors. Zur Überprüfung des Potentials werden im Rahmen einer Parameterstudie 47 unterschiedliche Nachleitgitter im Diffusor der Basis-Verdichterstufe am Heißgasprüfstand untersucht. Es stellt sich heraus, dass durch den Einsatz einer Nachleitbeschaufelung der Verdichterwirkungsgrad um bis zu 8 Prozentpunkte verbessert werden kann, die Kennfeldbreite jedoch nicht ausreicht, um die motorischen Anforderungen bezüglich der Pumpstabilität oder der Bremsleistung zu erfüllen. Resultierend aus diesen Erkenntnissen werden drei variable Verdichter entwickelt, mit dem Ziel, den Wirkungsgradvorteil beschaufelter Diffusoren mittels einer geometrischen Verstellbarkeit für den schweren Nutzfahrzeugmotor nutzbar zu machen. Die Bewertung hinsichtlich der Ziele und Anforderungen erfolgt anhand von Versuchen am Heißgas- sowie Vollmotorenprüfstand. Die Variabilität mit der geringsten Komplexität ist die Kombination aus starrem Nachleitgitter und Schubumluftventil. Das System zeichnet sich dadurch aus, dass Strömungsabrisse im Bereich des Nachleitgitters durch Aktivieren des Schubumluftventils und somit Öffnen eines Rezirkulationskanals im Verdichtergehäuse in pumpkritischen Situationen vermieden werden können. Der Verzicht auf bewegliche Teile im Diffusor resultiert in der höchsten Reduktion des Kraftstoffverbrauchs um 0,6 − 1,4% im Hauptfahrbereich. Der Doppeldiffusor besitzt zwei separate Strömungskanäle unterschiedlicher Geometrie, die im Betrieb durch eine axiale Verschiebung mit Druckluft aktiviert werden können. Dieses völlig neuartige Konzept ermöglicht es, die Auslegungsziele auf zwei Diffusoren aufzuteilen und somit für jede Kennfeldhälfte die jeweils optimale Schaufelgeometrie auszuwählen. Mit dieser Variabilität kann die Einspritzmenge im Hauptfahrbereich um 0,5 − 0,8 Prozent gesenkt werden. Das System mit der höchsten Komplexität ist der Verdichter mit rotierbarer Nachleitbeschaufelung. Über einen elektronischen Steller können die Anstellwinkel und Halsquerschnitte in jedem Betriebspunkt den Anströmbedingungen angepasst werden, um den jeweils bestmöglichen Wirkungsgrad zu erhalten. Aufgrund der anspruchsvollen geometrischen Zwangsbedingungen bei der Auswahl der Schaufelgeometrie besitzt der Dreh- schaufler mit 0,3−0,6% das geringste Potential zur Verbesserung der Kraftstoffsparsamkeit, erzielt jedoch das beste Ergebnis bezüglich der Bremsleistung und der Pumpstabilität.:1 Einleitung 1.1 Einführung 1.2 Stand der Technik 1.3 Zielsetzung 2 Grundlagen 2.1 Der schwere Nutzfahrzeugmotor 2.1.1 Aufbau 2.1.2 Kenngrößen 2.1.3 Motorbremse 2.2 Der Turbolader-Radialverdichter 2.2.1 Systembeschreibung 2.2.2 Definition von Kenngrößen 2.2.3 ThermodynamischeBeschreibung 2.3 Thermodynamik des Aufladesystems 2.3.1 Stationäre Lastkurven im Verdichterkennfeld 2.3.2 Grenzwerte im Stationärbetrieb 2.3.3 Transientverhalten 3 Methodik 3.1 Lösungsweg 3.2 Lastkollektivauswertung 3.3 Parametrisiertes Diffusormodell 3.3.1 Geometrischer Aufbau 3.3.2 Auslegungsgrößen 3.3.3 Parameterstudie 3.4 Simulation 3.4.1 1D-Strömungssimulation in Diffusor und Volute 3.4.2 3D-Strömungssimulation der Verdichterstufe 3.4.3 Motorprozesssimulation 3.5 Heißgasprüfstand 3.5.1 Kennfeldvermessung 3.5.2 Aerodynamikmessung 3.5.3 Verkokungsanfälligkeit 3.6 Motorprüfstand 3.6.1 Aufbau 3.6.2 Randbedingungen 3.6.3 Akustikmessung 4 Ergebnisse 4.1 Validierung 4.1.1 Strömungszustand am Verdichterradaustritt 4.1.2 Simulation der Verdichterstufe mit unbeschaufeltem Diffusor 4.1.3 Simulation der Verdichterstufe mit beschaufeltem Diffusor 4.2 Verlustanalyse Basisverdichter 4.2.1 Auswertung der Lastkollektive 4.2.2 Aerodynamische Verlustanalyse 4.2.3 Strömungsmechanik im Diffusor 4.3 Parameterstudie beschaufelter Diffusoren 4.3.1 Einfluss von Nachleitgittern auf das Verdichterkennfeld 4.3.2 Anforderungen des schweren Nutzfahrzeugmotors 4.4 Aerodynamik beschaufelter Diffusoren 4.4.1 Auslegungskriterien 4.5 Verkokung beschaufelter Diffusoren 5 Variable Verdichter 5.1 VRVC - Starres Nachleitgitter mit Schubumluftventil 5.1.1 Auslegung und Konstruktion 5.1.2 Heißgasprüfstand 5.2 VSVC-Doppeldiffusor 5.2.1 Auslegung und Konstruktion 5.2.2 Heißgasprüfstand 5.3 VPVC-RotierbareSchaufeln 5.3.1 Auslegung und Konstruktion 5.3.2 Heißgasprüfstand 5.4 Verhalten variabler Verdichter am schweren NFZ-Motor 5.4.1 Volllast 5.4.2 Lastvariation 5.4.3 DynamischesAnsprechverhalten 5.4.4 Low-End Torque 5.4.5 Dynamische Pumpstabilität 5.4.6 Bremsbetrieb 5.4.7 Ansteuerung 5.4.8 Akustik 5.5 Übersicht 6 Zusammenfassung und Ausblick 7 Anhang Literaturverzeichnis
Reducing the total costs of ownership, achieving the rated engine power and compliance with exhaust-emission legislation are competing goals regarding the development of heavy duty engines. This leads to demanding requirements for the aerodynamic design of the turbocharger compressor stage such as high efficiencies at various operating points and a broad map width. The aim of the present doctoral thesis is to investigate the potential of a compressor with variable geometry in order to obtain a better compromise between efficiency and compressor map width for the purpose of increasing fuel economy without sacrifices concerning the rated power, engine brake performance or surge stability. In a first step, the evaluation of load cycles yields operating points on which the fuel consumption is heavily dependent. Results of 1D- and 3D fluid flow simulations show that the high tangential velocity in the vaneless diffusor is the main cause for the reduction of compressor efficiency in the main driving range. A parameter study containing 47 different geometries is conducted at a hot gas test rig in order to examine the potential of vaned diffusers regarding the reduction of the tangential velocity component. It can be seen that by introducing diffuser vanes compressor efficiency can be increased by up to 8 percent. The narrow map width however prevents the use of a fixed geometry for heavy duty engines. Based on those results three variable geometry compressors are developed with the goal of maintaining the efficiency benefit of vaned diffusers while increasing the map width by adjustable geometric features. The evaluation of the variable compressor systems is based on hot gas and engine test bench measurements. The variable compressor system with the lowest complexity utilizes a recirculation valve in the compressor housing in combination with a fixed geometry vaned diffuser in order to improve the surge margin for a short period of time at a sudden load drop. The abandonment of functional gaps in the diffuser leads to the highest improvement of fuel economy of 0,6 − 1,4% in the main driving range. The compressor with stacked diffuser vanes has two separate flow channels in the diffuser. During engine operation only one vaned diffuser geometry is active. The axial movement is performed via pressure chambers in the compressor and bearing housing. The two diffuser geometries are either optimized for high or low mass flows. This way the fuel consumption in the main driving range can be reduced by 0,5 − 0,8%. The compressor with pivoting vanes in the diffuser has the highest complexity of all systems. With the aid of an electronic actuator the vane inlet angle and throat area can be adjusted to the impeller outlet flow conditions at each operating point. As a consequence the pivoting vanes compressor achieves the best results regarding engine brake performance and surge stability. The fuel economy in the main driving range can be improved by 0,3 − 0,6%. Higher benefits are prevented by demanding geometric constraints in order to ensure the rotatability of the vanes and to prevent vibrations of the impeller blades.:1 Einleitung 1.1 Einführung 1.2 Stand der Technik 1.3 Zielsetzung 2 Grundlagen 2.1 Der schwere Nutzfahrzeugmotor 2.1.1 Aufbau 2.1.2 Kenngrößen 2.1.3 Motorbremse 2.2 Der Turbolader-Radialverdichter 2.2.1 Systembeschreibung 2.2.2 Definition von Kenngrößen 2.2.3 ThermodynamischeBeschreibung 2.3 Thermodynamik des Aufladesystems 2.3.1 Stationäre Lastkurven im Verdichterkennfeld 2.3.2 Grenzwerte im Stationärbetrieb 2.3.3 Transientverhalten 3 Methodik 3.1 Lösungsweg 3.2 Lastkollektivauswertung 3.3 Parametrisiertes Diffusormodell 3.3.1 Geometrischer Aufbau 3.3.2 Auslegungsgrößen 3.3.3 Parameterstudie 3.4 Simulation 3.4.1 1D-Strömungssimulation in Diffusor und Volute 3.4.2 3D-Strömungssimulation der Verdichterstufe 3.4.3 Motorprozesssimulation 3.5 Heißgasprüfstand 3.5.1 Kennfeldvermessung 3.5.2 Aerodynamikmessung 3.5.3 Verkokungsanfälligkeit 3.6 Motorprüfstand 3.6.1 Aufbau 3.6.2 Randbedingungen 3.6.3 Akustikmessung 4 Ergebnisse 4.1 Validierung 4.1.1 Strömungszustand am Verdichterradaustritt 4.1.2 Simulation der Verdichterstufe mit unbeschaufeltem Diffusor 4.1.3 Simulation der Verdichterstufe mit beschaufeltem Diffusor 4.2 Verlustanalyse Basisverdichter 4.2.1 Auswertung der Lastkollektive 4.2.2 Aerodynamische Verlustanalyse 4.2.3 Strömungsmechanik im Diffusor 4.3 Parameterstudie beschaufelter Diffusoren 4.3.1 Einfluss von Nachleitgittern auf das Verdichterkennfeld 4.3.2 Anforderungen des schweren Nutzfahrzeugmotors 4.4 Aerodynamik beschaufelter Diffusoren 4.4.1 Auslegungskriterien 4.5 Verkokung beschaufelter Diffusoren 5 Variable Verdichter 5.1 VRVC - Starres Nachleitgitter mit Schubumluftventil 5.1.1 Auslegung und Konstruktion 5.1.2 Heißgasprüfstand 5.2 VSVC-Doppeldiffusor 5.2.1 Auslegung und Konstruktion 5.2.2 Heißgasprüfstand 5.3 VPVC-RotierbareSchaufeln 5.3.1 Auslegung und Konstruktion 5.3.2 Heißgasprüfstand 5.4 Verhalten variabler Verdichter am schweren NFZ-Motor 5.4.1 Volllast 5.4.2 Lastvariation 5.4.3 DynamischesAnsprechverhalten 5.4.4 Low-End Torque 5.4.5 Dynamische Pumpstabilität 5.4.6 Bremsbetrieb 5.4.7 Ansteuerung 5.4.8 Akustik 5.5 Übersicht 6 Zusammenfassung und Ausblick 7 Anhang Literaturverzeichnis