Sinonasal cysts causing dyspnoea in two cattle – case report

Two cattle were referred to the University Clinic for Ruminants of the University of Veterinary Medicine in Vienna. The main clinical sign in both cattle was dyspnoea with nasal stridor. Clinical examination of the upper respiratory tract was conducted, supplemented by ultrasonography, endoscopy and radiography. In addition, histological, bacteriological, and cytological examinations of different specimen materials were performed. The cow of Case 1 suffered from cystic nasal conchae, which was treated successfully by a laser technique. The cow of Case 2 also suffered from cystic nasal conchae. No surgery was performed in this case because the cyst opened spontaneously the day after diagnostic endoscopic procedures had been performed and the animal did not show any respiratory signs anymore. Pathological changes in the upper respiratory tract, such as nasal obstructions, should be included in the list of differential diagnoses in cattle showing respiratory distress

Potential of hybrid powertrains in a variable compression ratio downsized turbocharged VVA Spark Ignition engine

[EN] After the diesel emissions scandal, also known as Dieselgate, Direct Injection Spark-Ignited (DISI) internal combustion engines (ICE) appears as the most promising alternative to mitigate the harmful tailpipe emissions from passenger cars. In spite of that, the current ICE technologies are not enough to achieve the fuel consumption/CO2 emissions targets set by the new transportation legislation (4.1 L-gasoline/100 km, 95 gCO(2)/km for 2021). In this complex scenario, the electrification of the powertrain using high efficiency electric motors and battery package together with sophisticated DISI engines appears as potential solution to meet these requirements. The aim of this work is to study the fuel consumption and pollutant emissions in transient conditions from a passenger car equipped with a variable compression ratio (VCR) DISI engine and electrified powertrain technologies. The vehicle behavior was simulated by means of a 0D GT-Suite model fed by experimental results obtained in an engine test bench. Mild hybrid electric vehicle (MHEV) and full hybrid electric vehicle (FHEV) architectures using a VCR DISI engine were studied. Moreover, an optimization methodology is presented to select the best vehicle configuration in terms of hardware and control strategies by means of a design of experiments (DoE). The results show that VCR allows a fuel improvement of 3% with respect to the conventional DISI fixed CR along the worldwide harmonized light vehicles test cycles (WLTC). The benefits found when combining the VCR technology with hybrid powertrains are even higher. In this sense, the fuel improvements were higher as the electrification levels increased, with 8% for MHEV-VCR and around 20% for FHEV-VCR. In terms of emissions, the two clear benefits with FHEV-VCR were the reduction of particle number (PN) and unburned hydrocarbons (HC) of around 60% and 15%, respectively, as compared to the conventional DISI.The authors acknowledge FEDER and Spanish Ministerio de Economia y Competitividad for partially supporting this research through TRANCO project (TRA2017-87694-R). The authors also acknowledge the Universitat Politecnica de Valencia for partially supporting this research through Convocatoria de ayudas a Primeros Proyectos de Investigacion (SP20180148).García Martínez, A.; Monsalve-Serrano, J.; Martínez-Boggio, SD.; Wittek, K. (2020). Potential of hybrid powertrains in a variable compression ratio downsized turbocharged VVA Spark Ignition engine. Energy. 195:1-19. https://doi.org/10.1016/j.energy.2020.117039S119195González, R. M., Marrero, G. A., Rodríguez-López, J., & Marrero, Á. S. (2019). Analyzing CO2 emissions from passenger cars in Europe: A dynamic panel data approach. 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Multi-objective optimization design and performance evaluation for plug-in hybrid electric vehicle powertrains. Applied Energy, 208, 1608-1625. doi:10.1016/j.apenergy.2017.08.201Benajes, J., García, A., Monsalve-Serrano, J., & Martínez-Boggio, S. (2020). Emissions reduction from passenger cars with RCCI plug-in hybrid electric vehicle technology. Applied Thermal Engineering, 164, 114430. doi:10.1016/j.applthermaleng.2019.114430Asghar, M., Bhatti, A. I., Ahmed, Q., & Murtaza, G. (2018). Energy Management Strategy for Atkinson Cycle Engine Based Parallel Hybrid Electric Vehicle. IEEE Access, 6, 28008-28018. doi:10.1109/access.2018.2835395Solouk, A., Shakiba-herfeh, M., & Shahbakhti, M. (2017). Analysis and Control of a Torque Blended Hybrid Electric Powertrain with a Multi-Mode LTC-SI Engine. SAE International Journal of Alternative Powertrains, 6(1), 54-67. doi:10.4271/2017-01-1153Wang, C., Zhang, F., Wang, E., Yu, C., Gao, H., Liu, B., … Zhao, C. (2019). Experimental study on knock suppression of spark-ignition engine fuelled with kerosene via water injection. Applied Energy, 242, 248-259. doi:10.1016/j.apenergy.2019.03.123Wolfgang, S., Sorger, H., Loesch, S., Unzeitig, W., Huettner, T., & Fuerhapter, A. (2017). The 2-Step VCR Conrod System - Modular System for High Efficiency and Reduced CO2. SAE Technical Paper Series. doi:10.4271/2017-01-0634Wittek, K., Geiger, F., Andert, J., Martins, M., Cogo, V., & Lanzanova, T. (2019). Experimental investigation of a variable compression ratio system applied to a gasoline passenger car engine. Energy Conversion and Management, 183, 753-763. doi:10.1016/j.enconman.2019.01.037Kleeberg, H., Tomazic, D., Dohmen, J., Wittek, K., & Balazs, A. (2013). Increasing Efficiency in Gasoline Powertrains with a Two-Stage Variable Compression Ratio (VCR) System. SAE Technical Paper Series. doi:10.4271/2013-01-0288Teodosio, L., De Bellis, V., Bozza, F., & Tufano, D. (2017). Numerical Study of the Potential of a Variable Compression Ratio Concept Applied to a Downsized Turbocharged VVA Spark Ignition Engine. SAE Technical Paper Series. doi:10.4271/2017-24-0015Luján, J. M., García, A., Monsalve-Serrano, J., & Martínez-Boggio, S. (2019). Effectiveness of hybrid powertrains to reduce the fuel consumption and NOx emissions of a Euro 6d-temp diesel engine under real-life driving conditions. Energy Conversion and Management, 199, 111987. doi:10.1016/j.enconman.2019.111987Benajes, J., García, A., Monsalve-Serrano, J., & Martínez-Boggio, S. (2019). Optimization of the parallel and mild hybrid vehicle platforms operating under conventional and advanced combustion modes. Energy Conversion and Management, 190, 73-90. doi:10.1016/j.enconman.2019.04.010Morra, E., Spessa, E., Ciaravino, C., & Vassallo, A. (2012). Analysis of Various Operating Strategies for a Parallel-Hybrid Diesel Powertrain with a Belt Alternator Starter. 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Potential of a Two-Stage Variable Compression Ratio Downsized Spark Ignition Engine for Passenger Cars under different driving conditions

[EN] With the aim of reducing pollutant emissions from internal combustion engines (ICE), the application of stoichiometrically operated spark ignition (SI) engines, for light-duty vehicles, has been overcoming the compression ignition (CI) engines market share throughout the past years. The ability of a substantial reduction of the primary harmful emissions (HC, CO, and NOx) through the use of the simple three-way catalyst (TWC) is the main reason for that. Nonetheless, with increasing attention to CO2 emissions, the development of highly efficient downsized SI engines turn to be of enormous interest. The synergies of multiple systems such as direct injection, turbocharger, and variable valve actuation are able to lead the SI efficiencies closer to those of CI engines. However, to enable high load operation on such downsized engines, the compression ratio (CR) must be reduced due to knock limitations, reducing the partial-load operations efficiency. The implementation of two-stage variable compression ratio (VCR) systems enables the extraction of high thermal efficiency with high CR at lower loads and extended knock-free high load operation with low CR. In this study, the evaluation of a two-stage VCR system applied to a state-of-the-art downsized SI engine was made through standard driving cycle simulations. The VCR mechanism is composed of an eccentric element in the small end of the connecting rod, which is rotated to increase/decrease the effective connecting rod length, achieving the CRs of 12.11:1 and 9.56:1. The engine was run in an eddy-current dynamometer test bench throughout the essential operating range to obtain the brake specific fuel consumption (BSFC) map. The VCR mechanism CR switching delay was also experimentally characterized to derive a function of the operating conditions. The measured map was entered into the map-based driving cycle simulation with a sub-model to account for the isolated effects of the transient period encompassing the compression ratio switching. The results show that slow CR transitions lead to fuel consumption penalties, which suggests the need for optimizing the control strategies of the VCR system. Even though this penalty, once the gear up-shift speed is optimized for each driving cycle, the VCR system still enables fuel consumption reductions up to 3% on the WLTC driving cycle, up to 4% on the proposed urban driving cycles and up to 3% on highway driving cycles with respect to the fixed CR.This research has been partially funded by FEDER and the Spanish Government through project RTI2018-102025-B-I00. The authors also acknowledge the Universitat Politecnica de Valencia for partially supporting this research through Convocatoria de ayudas a Primeros Proyectos de Lnvestigacion (PAID-06-18).López, JJ.; García Martínez, A.; Monsalve-Serrano, J.; Vielmo-Cogo, V.; Wittek, K. (2020). Potential of a Two-Stage Variable Compression Ratio Downsized Spark Ignition Engine for Passenger Cars under different driving conditions. Energy Conversion and Management. 203:1-15. https://doi.org/10.1016/j.enconman.2019.112251S115203Amelang S, Wehrmann B. Dieselgate – a timeline of Germany’s car emissions fraud scandal | Clean Energy Wire n.d. https://www.cleanenergywire.org/factsheets/dieselgate-timeline-germanys-car-emissions-fraud-scandal (accessed September 2, 2019).Luján, J. M., Bermúdez, V., Dolz, V., & Monsalve-Serrano, J. (2018). An assessment of the real-world driving gaseous emissions from a Euro 6 light-duty diesel vehicle using a portable emissions measurement system (PEMS). 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