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    Abstract State Machines 1988-1998: Commented ASM Bibliography

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    An annotated bibliography of papers which deal with or use Abstract State Machines (ASMs), as of January 1998.Comment: Also maintained as a BibTeX file at http://www.eecs.umich.edu/gasm

    Design and Numerical Analysis of Flow Characteristics in a Scaled Volute and Vaned Nozzle of Radial Turbocharger Turbines

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    [EN] Over the past few decades, the aerodynamic improvements of turbocharger turbines contributed significantly to the overall efficiency augmentation and the advancements in downsizing of internal combustion engines. Due to the compact size of automotive turbochargers, the experimental measurement of the complex internal aerodynamics has been insufficiently studied. Hence, turbine designs mostly rely on the results of numerical simulations and the validation of zero-dimensional parameters as efficiency and reduced mass flow. To push the aerodynamic development even further, a precise validation of three-dimensional flow patterns predicted by applied computational fluid dynamics (CFD) methods is in need. This paper presents the design of an up-scaled volute-stator model, which allows optical experimental measurement techniques. In a preliminary step, numerical results indicate that the enlarged geometry will be representative of the flow patterns and characteristic non-dimensional numbers at defined flow sections of the real size turbine. Limitations due to rotor-stator interactions are highlighted. Measurement sections of interest for available measurement techniques are predefined.The authors disclose receipt of the following financial support for the research, authorship, and/or publication of this article: This work was partly sponsored by the program "Ayuda a Primeros Proyectos de Investigacion (PAID-06-18), Vicerrectorado de Investigacion, Innovacion y Transferencia de la Universitat Politecnica de Valencia (UPV), Spain". The support given to Ms. N.H.G. by Universitat Politecnica de Valencia through the "FPI-Subprograma 2" (No.FPI-2018-S2-1368) grant within the "Programa de Apoyo para la Investigacion y Desarrollo (PAID-01-18)" is gratefully acknowledgedTiseira, A.; Navarro, R.; Inhestern, LB.; Hervás-Gómez, N. (2020). Design and Numerical Analysis of Flow Characteristics in a Scaled Volute and Vaned Nozzle of Radial Turbocharger Turbines. Energies. 13(11):1-19. https://doi.org/10.3390/en13112930S1191311Praveena, V., & Martin, M. L. J. (2018). A review on various after treatment techniques to reduce NOx emissions in a CI engine. Journal of the Energy Institute, 91(5), 704-720. doi:10.1016/j.joei.2017.05.010Sindhu, R., Amba Prasad Rao, G., & Madhu Murthy, K. (2018). Effective reduction of NOx emissions from diesel engine using split injections. Alexandria Engineering Journal, 57(3), 1379-1392. doi:10.1016/j.aej.2017.06.009Gil, A., Tiseira, A. O., García-Cuevas, L. M., Usaquén, T. R., & Mijotte, G. (2018). Fast three-dimensional heat transfer model for computing internal temperatures in the bearing housing of automotive turbochargers. International Journal of Engine Research, 21(8), 1286-1297. doi:10.1177/1468087418804949Suhrmann, J. F., Peitsch, D., Gugau, M., & Heuer, T. (2012). On the Effect of Volute Tongue Design on Radial Turbine Performance. Volume 8: Turbomachinery, Parts A, B, and C. doi:10.1115/gt2012-69525Roumeas, M., & Cros, S. (2012). Aerodynamic Investigation of a Nozzle Clearance Effect on Radial Turbine Performance. Volume 8: Turbomachinery, Parts A, B, and C. doi:10.1115/gt2012-68835Liu, Y., Yang, C., Qi, M., Zhang, H., & Zhao, B. (2014). Shock, Leakage Flow and Wake Interactions in a Radial Turbine With Variable Guide Vanes. Volume 2D: Turbomachinery. doi:10.1115/gt2014-25888Cornolti, L., Onorati, A., Cerri, T., Montenegro, G., & Piscaglia, F. (2013). 1D simulation of a turbocharged Diesel engine with comparison of short and long EGR route solutions. Applied Energy, 111, 1-15. doi:10.1016/j.apenergy.2013.04.016Bohbot, J., Chryssakis, C., & Miche, M. (2006). Simulation of a 4-Cylinder Turbocharged Gasoline Direct Injection Engine Using a Direct Temporal Coupling Between a 1D Simulation Software and a 3D Combustion Code. SAE Technical Paper Series. doi:10.4271/2006-01-3263Inhestern, L. B. (s. f.). Measurement, Simulation, and 1D-Modeling of Turbocharger Radial Turbines at Design and Extreme Off-Design Conditions. doi:10.4995/thesis/10251/119989Tamaki, H., & Unno, M. (2008). Study on Flow Fields in Variable Area Nozzles for Radial Turbines. International Journal of Fluid Machinery and Systems, 1(1), 47-56. doi:10.5293/ijfms.2008.1.1.047Eroglu, H., & Tabakoff, W. (1991). LDV Measurements and Investigation of Flow Field Through Radial Turbine Guide Vanes. Journal of Fluids Engineering, 113(4), 660-667. doi:10.1115/1.2926531Karamanis, N., Martinez-Botas, R. F., & Su, C. C. (2000). Mixed Flow Turbines: Inlet and Exit Flow Under Steady and Pulsating Conditions. Volume 1: Aircraft Engine; Marine; Turbomachinery; Microturbines and Small Turbomachinery. doi:10.1115/2000-gt-0470Galindo, J., Tiseira Izaguirre, A. O., García-Cuevas, L. M., & Hervás Gómez, N. (2020). Experimental approach for the analysis of the flow behaviour in the stator of a real centripetal turbine. International Journal of Engine Research, 22(6), 2010-2020. doi:10.1177/1468087420916281Dufour, G., Carbonneau, X., Cazalbou, J.-B., & Chassaing, P. (2006). Practical Use of Similarity and Scaling Laws for Centrifugal Compressor Design. Volume 6: Turbomachinery, Parts A and B. doi:10.1115/gt2006-91227Tancrez, M., Galindo, J., Guardiola, C., Fajardo, P., & Varnier, O. (2011). Turbine adapted maps for turbocharger engine matching. Experimental Thermal and Fluid Science, 35(1), 146-153. doi:10.1016/j.expthermflusci.2010.07.018Menter, F. R. (1994). Two-equation eddy-viscosity turbulence models for engineering applications. AIAA Journal, 32(8), 1598-1605. doi:10.2514/3.12149Broatch, A., Galindo, J., Navarro, R., & García-Tíscar, J. (2014). Methodology for experimental validation of a CFD model for predicting noise generation in centrifugal compressors. International Journal of Heat and Fluid Flow, 50, 134-144. doi:10.1016/j.ijheatfluidflow.2014.06.006Smirnov, P. E., Hansen, T., & Menter, F. R. (2007). Numerical Simulation of Turbulent Flows in Centrifugal Compressor Stages With Different Radial Gaps. Volume 6: Turbo Expo 2007, Parts A and B. doi:10.1115/gt2007-27376Serrano, J. R., Olmeda, P., Arnau, F. J., Dombrovsky, A., & Smith, L. (2014). Analysis and Methodology to Characterize Heat Transfer Phenomena in Automotive Turbochargers. Journal of Engineering for Gas Turbines and Power, 137(2). doi:10.1115/1.4028261Serrano, J. R., Olmeda, P., Arnau, F. J., Dombrovsky, A., & Smith, L. (2015). Turbocharger heat transfer and mechanical losses influence in predicting engines performance by using one-dimensional simulation codes. Energy, 86, 204-218. doi:10.1016/j.energy.2015.03.130Serrano, J. R., Tiseira, A., García-Cuevas, L. M., Inhestern, L. B., & Tartoussi, H. (2017). Radial turbine performance measurement under extreme off-design conditions. Energy, 125, 72-84. doi:10.1016/j.energy.2017.02.118Serrano, J. R., Gil, A., Navarro, R., & Inhestern, L. B. (2017). Extremely Low Mass Flow at High Blade to Jet Speed Ratio in Variable Geometry Radial Turbines and its Influence on the Flow Pattern: A CFD Analysis. Volume 8: Microturbines, Turbochargers and Small Turbomachines; Steam Turbines. doi:10.1115/gt2017-63368Serrano, J. R., Navarro, R., García-Cuevas, L. M., & Inhestern, L. B. (2019). Contribution to tip leakage loss modeling in radial turbines based on 3D flow analysis and 1D characterization. International Journal of Heat and Fluid Flow, 78, 108423. doi:10.1016/j.ijheatfluidflow.2019.108423Choi, M., Baek, J. H., Chung, H. T., Oh, S. H., & Ko, H. Y. (2008). Effects of the low Reynolds number on the loss characteristics in an axial compressor. Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy, 222(2), 209-218. doi:10.1243/09576509jpe520Klausner, E., & Gampe, U. (2014). Evaluation and Enhancement of a One-Dimensional Performance Analysis Method for Centrifugal Compressors. Volume 2D: Turbomachinery. doi:10.1115/gt2014-25141Tiainen, J., Jaatinen-Värri, A., Grönman, A., Turunen-Saaresti, T., & Backman, J. (2018). Effect of FreeStream Velocity Definition on Boundary Layer Thickness and Losses in Centrifugal Compressors. Journal of Turbomachinery, 140(5). doi:10.1115/1.4038872Vinuesa, R., Hosseini, S. M., Hanifi, A., Henningson, D. S., & Schlatter, P. (2017). Pressure-Gradient Turbulent Boundary Layers Developing Around a Wing Section. Flow, Turbulence and Combustion, 99(3-4), 613-641. doi:10.1007/s10494-017-9840-

    Accuracy and precision of an intraoral scanner in complex prosthetic rehabilitations: an in vitro study

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    The main purpose of this study is to measure the accuracy and the precision of the intraoral optical scanner CS3500® (Carestream Dental LLC, Atlanta, USA) in complex clinical situations as full arch rehabilitations on impl ants. 50 scans of the acrylic resin model were performed by using CS3500® (Carestream Dental LLC, Atlanta, USA) scanner. Each scan was compared with the virtual model derived from scanning with the laboratory scanner Dscan3® (Enhanced Geometry Soluti on, Bologna, Italy) to measure a possible misalignment. The alignment error was found to be 79,6 ( ± 12,87)  m. The measurement was taken at the level of 2 distal scan - abutments. The scanner's precision ranges from 24 to 52  m , depending on the dist ance between scan - abutment. CS3500® (Carestream Dental LLC, Atlanta, USA) intraoral scanner has detected a valid device in the execution of complex rehabilitations on implants. His accuracy and precision values fall within the range established in li terature to define acceptable the prosthetic fitting on full arch implant rehabilitation
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