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534 542 17 5 ; S ; [EN] Cylinder resonance phenomenon in reciprocating engines consists of high-frequency pressure oscillations excited by the combustion. The frequency of these oscillations is proportional to the speed of sound on pent-roof combustion chambers and henceforth the resonance frequency can be used to estimate the trapped mass, but in bowl-in-piston chambers a geometrical factor must be added in order to deal with the bowl disturbance. This paper applies the finite element method (FEM) to provide a resonance calibration for new design combustion chambers, which are commonly dominated by the bowl geometry near the top dead centre. The resonance calibration does not need any sensor information when it is solved by a FEM procedure, and consequently, is free from measurement errors. The calibration is proven to be independent of the chamber conditions and the results obtained are compared with experimental data by using spectral techniques and measuring precisely the trapped mass.[EN] This research has been partially supported by the European Union in framework of the POWERFUL project, seventh framework program FP7/2007-2013, theme 7, sustainable surface transport (grant agreement number SCP8-GA-2009-234032). Broatch Jacobi, JA.; Guardiola, C.; Bares-Moreno, P.; Denia Guzmán, FD. (2016). Determination of the resonance response in an engine cylinder with a bowl-in-piston geometry by the finite element method for inferring the trapped mass. International Journal of Engine Research. 17(5):534-542. https://doi.org/10.1177/1468087415589701 Powell, J. D. (1993). Engine Control Using Cylinder Pressure: Past, Present, and Future. Journal of Dynamic Systems, Measurement, and Control, 115(2B), 343-350. doi:10.1115/1.2899074 Desantes, J. M., Galindo, J., Guardiola, C., & Dolz, V. (2010). Air mass flow estimation in turbocharged diesel engines from in-cylinder pressure measurement. Experimental Thermal and Fluid Science, 34(1), 37-47. doi:10.1016/j.expthermflusci.2009.08.009 Finol, C. A., & Robinson, K. ...

The unprecedented cultural consciousness after decades of black cultural suppression in the South African public life since the 1990s summons us to the need to harness African ecclesiopolitical symbols in public life. This task is executed at a time when the notions of inter alia, spirituality and Imvuselelo are at the heart of the combustion chambers of our public and political life. Imvuselelo is a thermometer of decolonialist rebellion – the militant spirituality linked with Tiyo Soga – and is a self-combustion escape route in instances of black African epistemicide and violence. The heuristic device of iziko (fireplace) is employed to illuminate and locate the reestablishment and anamnestic praxis of protological life-giving foundations of spirituality in the African universe in our interpretation of Imvuselelo. The notion of imvuselelo is illuminated through iziko to debunk the incompatibilities, disharmonies, incongruences and conflagrations of virtual spirituality in its capture and domestication of the resources of the downtrodden. ; http://www.hts.org.za ; am2017 ; Dogmatics and Christian Ethics

The study of non-circular jet flows has become important due to their various applications such as aircraft exhaust, combustion chambers and injectors. The goal of present paper is to examine the impact of elliptical, square, and triangular shaped orifices on the mixing characteristics of a free jet with Mach number 0.8. Numerical simulations using an SST K-ω two-equation turbulence model were conducted with a Reynolds number of 3.46×105 for all cases. The mean velocity, decay rate, half-velocity width, spread rate, and turbulence intensity of the jet were analysed. The results showed that the triangular orifice provided the best mixing efficiency, with a shorter jet core length. The decay rate was found to be lowest for the square jet and highest for the triangular jet, which matches with the previous research. The asymmetric jets experienced two axis-switching points, while the square jet experienced a 450 rotation of its axes but no axis-switching. The core region had lower turbulence levels, while the highest turbulence levels were in the shear layer.

This article is about the rise and fall of ocean incineration, a method for the disposal of hazardous chemical waste that was initiated in the late 1960s, developed, tested, and perfected throughout the 1970s, commercialized in the 1980s, and eventually phased out from the 1990s onwards. Ocean incineration consisted in the offshore destruction of toxic liquid substances in specially designed ships outfitted with high-temperature combustion chambers and high stacks. When this technology broke through, it seemed like a panacea. It heralded the safe disposal of noxious compounds such as organochlorines and polychlorinated biphenyls (PCBs), which were ubiquitous by-products of petrochemical industrial processes. It promised to minimize private companies' externalities and ease environmental concerns. But it ultimately failed to provide an alternative to safely disposing of toxic waste. What does explain such a decline? This article answers this question by arguing that the demise of ocean incineration was due to the combination of locally oriented and transnationally driven protests, which emerged across the (North) Atlantic and exposed the dangerous and highly exploitative nature of such a practice.

The U.S. government, military, and industry once saw ocean incineration as the safest and most efficient way to dispose of hazardous chemical waste. Beginning in the late 1960s, toxic chemicals such as PCBs and other harmful industrial byproducts were taken out to sea to be destroyed in specially designed ships equipped with high-temperature combustion chambers and smokestacks. But public outcry arose after the environmental and health risks of ocean incineration were exposed, and the practice was banned in the early 1990s.Smoke on the Water traces the rise and fall of ocean incineration, showing how a transnational environmental movement tested the limits of U.S. political and economic power. Dario Fazzi examines the anti-ocean-incineration movement that emerged on both sides of the Atlantic, arguing that it succeeded by merging local advocacy with international mobilization. He emphasizes the role played at the grassroots level by women, migrant workers, and other underrepresented groups who were at greatest risk. Environmental groups, for their part, gathered and shared evidence about the harms of at-sea incineration, building scientific consensus and influencing international debates.Smoke on the Water tells the compelling story of a campaign against environmental degradation in which people from marginalized communities took on the might of the U.S. military-industrial complex. It offers new insights into the transnational dimensions of environmental regulation, the significance of nonstate actors in international history, and the making of environmental justice movements

El presente trabajo muestra la construcción y evaluación del empuje de un motor pulsorreactor, presentando una modificación respecto del diseño original hecha en el difusor la cual dio como resultado una mejor combustión y desempeño del motor. El prototipo del motor pulsorreactor construido tiene una longitud de 0,85 m con una masa de 2,87 kg y desarrolló en condiciones estables una fuerza de empuje promedio de 21 ,9 N con una frecuencia de pulsos de combustión comprendido entre 12,0 y 14,0 Hz todos estos resultados determinados con los equipos, software y maquinas herramientas disponibles en los talleres de Ingeniería Mecánica y laboratorio de Física de la Universidad Nacional del Callao. El motor pulsorreactor construido representa un equipo potencial para futuras investigaciones y aplicaciones en cámaras de combustión, aeromodelismo e industria militar. ; The present work shows the construction and evaluation of the thrust force of a pulse-jet engine, presenting a modification 1 concern of the original design done in the diffuser which gave like proved a better combustion and performance of the·engine. The prototype of the constructed pulse-jet engine has a length of 0,85 m with a mass of 2,87 kg and developed in stable conditions a force of average thrust of 21 ,9 N with a frequency of pulses of combustion understood between 12,0 and 14,0 Hz all these results determined with the equipments software and you scheme available tools in the workshops of Mechanical Engineering and laboratory of Physics of the National University of the Callao. The constructed pulse-jet engine represents a potential equipment for future investigations and applications in chambers of combustion, model aircraft flying and military industry.

The article explores the relationship between the state and organised business interests in Germany during the Covid-19 crisis of 2020. Two questions are addressed: Whether and how do employers' associations, business interest associations and economic chambers articulate themselves in the context of the Covid-19 crisis? Does their interaction with the state follow the pattern of a dedicated 'crisis corporatism'? The starting point is the concept of path-dependence and the revitalisation of established patterns of state-business-interaction in the crisis. The study focuses on the period between March 2020 and February 2021. Based on an investigation of the forms and frequencies of state-business-interactions, three phases are identified and then analysed in detailed case studies. For the early phase of the Covid-19 pandemic (March–June 2020) a) information offers and political demands of employers' associations, business interest associations and economic chambers are examined quantitatively and b) the congruence between the groups' demands and the political measures introduced with the economic stimulus package is investigated. For the second phase (July–September 2020) a case study of the branch-specific 'automotive corporatism' during the crisis is presented. Finally, the analysis focuses on the growing distance between business' demands and government in the third phase (October 2020–February 2021). As a result, the article observes a 'corporatism without combustion engine', which is characterised and maintained by resource dependencies, network ties and a crisis-corporatist exchange between government and organised business interests.

Many industrial combustion processes produce carbon dioxide (CO2) at high temperature, which may be electrically recycled into valuable chemicals using microorganisms as catalysts. However, little attention has been paid to handle the remaining heat of these processes as an alternative to increase CO2 fixation and production rates. Thus, this study was aimed at steering electro bio-CO2 recycling into organic compounds under thermophilic conditions. A mesophilic anaerobic sludge was adapted in lab-scale reactors at 50 °C, developing a resilient biocathode. High amounts of acetate (5250 mg L−1) were accumulated during a long-term operation period (150 days). The maximum production rate was 28 g acetate per m2 per d, with columbic efficiencies over 80%. In terms of carbon (C) conversion, 0.31 kg of C as acetate were obtained per 1 kg of C as CO2 inlet, with an energy demand of 24 kW h per 1 kg of acetate. Thermoanaerobacterales appeared to dominate the cathodic chambers, though they were compartmentalized by distinct bacterial communities in the electrode biofilm compared to the bulk liquid. This research delves into the sustained ability of a mixed microbial culture to electrochemically produce organic compounds at 50 °C and considers the possibility of using CO2-saturated effluents from industrial heated point sources to bring the technology closer to its scale-up. ; This study has received funding from the European Union's Horizon 2020 research and innovation program under the grant agreement no. 760431. L. R.-A. acknowledges the support from the Catalan Government (2018 FI-B 00347) in the European FSE program (CCI 2014ES05SFOP007). E. P.-V. is grateful for the Research Training grant from the University of Girona (IFUdG2018/52). S. P. is a Serra Húnter Fellow (UdG-AG-575) and acknowledges the funding from the ICREA Acadèmia award. LEQUIA and IEA have been both recognized as consolidated research groups by the Catalan Government (2017-SGR-1552 and 2017-SGR-548)

Machine generated contents note: Chapter 1. Air pollution control 101 It is separation technology Wet collection of particulate Dry collection Gas absorption The concept of number of transfer units in absorption The transfer unit concept in gas absorption Hybrid systems Chapter 2. Adsorption devices Device type Typical applications and uses Operating principles Primary mechanisms used Design basics Operating suggestions Chapter 3. Biofilters Device type Typical applications and uses Operating principles Primary mechanisms used Design basics Operating suggestions Chapter 4. Dry cyclone collectors Device type Typical applications and uses Operating principles Primary mechanisms used Design basics Operating/application suggestions Chapter 5. Electrostatic precipitators Device type Typical applications and uses Operating principles Primary mechanisms used Creation of charge Field charging Diffusion charging Design basics Resistivity of dust Operating suggestions Air load/gas load testing Alignment Thermal expansion Air in-leakage Rapping Insulator cleaning Purge heater and ring heater systems Process temperature Fuel changes Chapter 6. Evaporative coolers Device type Typical applications and uses Primary mechanisms used Design basics Types of gas cooling Gas conditioning Basic sizing The all important atomization A case history example Cost considerations Operating suggestions Chapter 7. Fabric filter collectors Device type Typical applications and uses Operating principles Primary mechanisms used Design basics Operating suggestions Chapter 8. Fiberbed filters Device type Typical applications and uses Acid mist Asphalt processing Plasticizer/vinyl/PVC processing Coating/laminating Electronics Textile processing Metalworking Lube oil vents and reservoirs Incinerator emissions Internal combustion engine crankcase vents Precious metal recovery Vacuum pumps Operating principles Primary mechanisms used Design basics Operating/application suggestions Filter cleaning Fiberbed filter life Fire protection if the contaminant is combustible Chapter 9. Filament (mesh pad) scrubbers Device type Typical applications Operating principles Primary mechanisms used Design basics Operating suggestions Chapter 10. Fluidized bed scrubbers Device type Typical applications and uses Operating principles Primary mechanisms used Design basics Operating suggestions Chapter 11. Mechanically aided scrubbers Device type Typical applications and uses Operating principles Primary mechanisms used Design basics Operating suggestions Chapter 12. Packed towers Device type Typical applications and uses Operating principles Primary mechanisms used Design basics Counter flow Cross flow Operating suggestions Chapter 13. Settling chambers Device type Typical applications and uses Operating principles Primary mechanisms used Design basics Operating/application suggestions Chapter 14. Spray towers/scrubbers Device type Typical applications and uses Operating principles Primary mechanisms used Design basics Operating suggestions Chapter 15. Nitrogen oxide (NOx) control Device type Typical applications and uses Combustion sources Operating principles Primary mechanisms used Design basics Different forms of NOx NOx measurement units Thermal NOx Fuel-bound NOx Thermal-NOx control strategies Dilution strategies Staging strategies Postcombustion strategies Operating/application suggestions Chapter 16. Thermal oxidizers Device type Typical applications Operating principles Primary mechanisms used Design basics Operating suggestions Chapter 17. Tray scrubbers Device type Typical applications and uses Operating principles Primary mechanism used Design basics Operating suggestions Chapter 18. Vane type scrubbers Device type Typical applications Operating principles Primary mechanisms used Design basics Operating suggestions Chapter 19. Venturi scrubbers Device type Typical applications Operating principles Primary mechanisms used Design basics Operating/application suggestions Chapter 20. Wet electrostatic precipitators Device type Typical applications and uses Primary mechanisms used Design basics Types of wet precipitators Configuration Arrangement Irrigation method Selecting a wet electrostatic precipitator Operating suggestions Appendix A: Additional selected reading General topics Industrial ventilation Air pollution engineering manual Fan engineering McIllvaine scrubber manual Psychrometric tables and charts Cameron hydraulic book Mass transfer operations Various corrosion guides Publication details

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

Land reclamation of oil sands disturbed boreal forests in Alberta is a challenging task facing companies with surface mine leases. The government requires reclamation to equivalent land capability, which is a vague statement at best. Agronomic theories and methodologies have been applied in the past with mixed success. We believe that ecological theory and new methods, designed to tease apart ecosystem function, should be applied to reclaiming ecosystems similar to native forests. This new reclamation ecology should start with disturbance theory and in boreal Alberta that means recovery from wildfire. All organisms in boreal forests, from the biggest trees to the smallest bacterium, are adapted to regular pulses of fire. Fire causes plant mortality and therefore changes in competition and resource availability. It also results in the partial combustion of organic matter, which creates pyrogenic carbon (PyC) and changes the soil chemical environment. Pyrogenic C is the substrate legacy of fire. It is resistant to decomposition and remains in the soil for hundreds of years. It has high surface area and adsorbs organic and inorganic compounds readily, which affects the availability of nutrients. It can be manufactured by an industrial process called pyrolysis, where is referred to as biochar. We believe that rebuilding native forest soils in the reclamation environment will require the use of biochar to stimulate functional similarity to native ecosystems, in terms of nutrient availability and microbial community succession. This is because peat is being used as a reclamation surface soil, but does not follow the typical first-order decomposition kinetics of native forest soils, due to distinct differences in organic matter quality. We believe that PyC will help to align peat decomposition kinetics and retain nutrients in surface soils. We also believe that it will create microbial community diversity and structure to be similar to the NFS. A 90 day laboratory incubation was conducted to examine the effect of PyC additions on carbon (C) and nitrogen (N) mineralization in two common oil sands reclamation surface soils, peat mineral mix (PMM) and forest floor mineral mix (FFM), and one native forest soil (NFS) recovering from wildfire. Three different kinds of PyC were used in the incubation, including charcoal collected from a local wildfire event, biochar pyrolyzed from willow chips, and petroleum coke, a by-product of oil sands upgrading. Micro-lysimeter chambers were used to build small soil columns of each soil type, to which PyC was added in replicate. These micro-lysimeters allowed for gas sampling from a soil head space for analysis of microbial respiration and therefore activity, and soil solution sampling for analysis of inorganic N. Samples were collected and analyzed on days 0, 1, 3, 7, 10, 14 and then every week after that for the duration of the incubation. After incubation, soil samples were extracted for microbial sequencing by paired end Illumina sequencing of the 16S rRNA gene for bacteria and ITS 1-2 gene for fungi to examine microbial community diversity and structure. Results indicated that the different PyC types increased C mineralization compared to the control, which suggests that it stimulates microbial activity and therefore respiration similar to the NFS. Literature also suggests that it undergoes some surface modifications at the molecular level upon addition to soils, which we also feel is reflected in the increased respiration. In contrast, PyC caused a decrease in N mineralization, which we believe is the result of N retention on PyC. This stems mostly from the fact that it is counter-intuitive that microbial activity would be increased (respiration), but the product of that activity (inorganic N) decreased. In reality, it is incredibly difficult to measure nutrient retention on PyC, but some literature provides evidence for this theory. PyC did not align decomposition kinetics for PMM as we believed it would, except in the case of N mineralization with biochar perhaps making it a soil amendment worth more attention. Pet-coke consistently performed the same or worse than the control in terms of C and N mineralization. Molecular sequencing of bacterial DNA showed that PyC, except for pet-coke, increased diversity in both the FFM and NFS, but not PMM which was higher to begin with. In ordination space, there is clear microbial succession from the control to the biochar, which indicates that biochar has a strong effect on the community structure. Fungal sequencing indicated that FFM had the highest diversity which was lowered by biochar to the level of NFS. However, no clear effect of PyC could be established for fungal community structure. These results clearly indicate that the addition of PyC has an effect on C and N mineralization, and microbial community diversity and structure in oil sands reclamation surface soils. The direction and magnitude of the effects has some similarity to the effect of PyC in NFS, and therefore should be considered as a soil amendment. However, the full interpretation of these results requires more work in terms of prescribing surface soil mixtures that will lead to a high degree of similarity between reclaimed ecosystems and native ecosystems. This work provides some preliminary evidence to support a paradigm shift towards reclamation ecology.

Land reclamation of oil sands disturbed boreal forests in Alberta is a challenging task facing companies with surface mine leases. The government requires reclamation to equivalent land capability, which is a vague statement at best. Agronomic theories and methodologies have been applied in the past with mixed success. We believe that ecological theory and new methods, designed to tease apart ecosystem function, should be applied to reclaiming ecosystems similar to native forests. This new reclamation ecology should start with disturbance theory and in boreal Alberta that means recovery from wildfire. All organisms in boreal forests, from the biggest trees to the smallest bacterium, are adapted to regular pulses of fire. Fire causes plant mortality and therefore changes in competition and resource availability. It also results in the partial combustion of organic matter, which creates pyrogenic carbon (PyC) and changes the soil chemical environment. Pyrogenic C is the substrate legacy of fire. It is resistant to decomposition and remains in the soil for hundreds of years. It has high surface area and adsorbs organic and inorganic compounds readily, which affects the availability of nutrients. It can be manufactured by an industrial process called pyrolysis, where is referred to as biochar. We believe that rebuilding native forest soils in the reclamation environment will require the use of biochar to stimulate functional similarity to native ecosystems, in terms of nutrient availability and microbial community succession. This is because peat is being used as a reclamation surface soil, but does not follow the typical first-order decomposition kinetics of native forest soils, due to distinct differences in organic matter quality. We believe that PyC will help to align peat decomposition kinetics and retain nutrients in surface soils. We also believe that it will create microbial community diversity and structure to be similar to the NFS. A 90 day laboratory incubation was conducted to examine the effect of PyC additions on carbon (C) and nitrogen (N) mineralization in two common oil sands reclamation surface soils, peat mineral mix (PMM) and forest floor mineral mix (FFM), and one native forest soil (NFS) recovering from wildfire. Three different kinds of PyC were used in the incubation, including charcoal collected from a local wildfire event, biochar pyrolyzed from willow chips, and petroleum coke, a by-product of oil sands upgrading. Micro-lysimeter chambers were used to build small soil columns of each soil type, to which PyC was added in replicate. These micro-lysimeters allowed for gas sampling from a soil head space for analysis of microbial respiration and therefore activity, and soil solution sampling for analysis of inorganic N. Samples were collected and analyzed on days 0, 1, 3, 7, 10, 14 and then every week after that for the duration of the incubation. After incubation, soil samples were extracted for microbial sequencing by paired end Illumina sequencing of the 16S rRNA gene for bacteria and ITS 1-2 gene for fungi to examine microbial community diversity and structure. Results indicated that the different PyC types increased C mineralization compared to the control, which suggests that it stimulates microbial activity and therefore respiration similar to the NFS. Literature also suggests that it undergoes some surface modifications at the molecular level upon addition to soils, which we also feel is reflected in the increased respiration. In contrast, PyC caused a decrease in N mineralization, which we believe is the result of N retention on PyC. This stems mostly from the fact that it is counter-intuitive that microbial activity would be increased (respiration), but the product of that activity (inorganic N) decreased. In reality, it is incredibly difficult to measure nutrient retention on PyC, but some literature provides evidence for this theory. PyC did not align decomposition kinetics for PMM as we believed it would, except in the case of N mineralization with biochar perhaps making it a soil amendment worth more attention. Pet-coke consistently performed the same or worse than the control in terms of C and N mineralization. Molecular sequencing of bacterial DNA showed that PyC, except for pet-coke, increased diversity in both the FFM and NFS, but not PMM which was higher to begin with. In ordination space, there is clear microbial succession from the control to the biochar, which indicates that biochar has a strong effect on the community structure. Fungal sequencing indicated that FFM had the highest diversity which was lowered by biochar to the level of NFS. However, no clear effect of PyC could be established for fungal community structure. These results clearly indicate that the addition of PyC has an effect on C and N mineralization, and microbial community diversity and structure in oil sands reclamation surface soils. The direction and magnitude of the effects has some similarity to the effect of PyC in NFS, and therefore should be considered as a soil amendment. However, the full interpretation of these results requires more work in terms of prescribing surface soil mixtures that will lead to a high degree of similarity between reclaimed ecosystems and native ecosystems. This work provides some preliminary evidence to support a paradigm shift towards reclamation ecology.