Analysis of temperature and altitude effects on the Global Energy Balance during WLTC

This is the author¿s version of a work that was accepted for publication in International Journal of Engine Research. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published as https://doi.org/10.1177/14680874211034292[EN] In this work, the Global Energy Balance (GEB) of a 1.6 L compression ignition engine is analyzed during WLTC using a combination of experimental measurements and simulations, by means of a Virtual Engine. The energy split considers all the relevant energy terms at two starting temperatures (20 degrees C and 7 degrees C) and two altitudes (0 and 1000 m). It is shown that reducing ambient temperature from 20 degrees C to -7 degrees C decreases brake efficiency by 1% and increases fuel consumption by 4%, mainly because of the higher friction due to the higher oil viscosity, while the effect of increasing altitude 1000 m decreases brake efficiency by 0.8% and increases fuel consumption by 2.5% in the WLTC mainly due to the change in pumping. In addition, GEB shows that ambient temperature is affecting exhaust enthalpy by 4.5%, heat rejection to coolant by 2%, and heat accumulated in the block by 2.5%, while altitude does not show any remarkable variations other than pumping and break power.The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This research has been partially funded by the European Union's Horizon 2020 Framework Programme for research, technological development and demonstration under grant agreement 723976 ("DiePeR'') and by the Spanish government under the grant agreement TRA2017-89894-R ("MECOEM'') and Sushma Artham was supported by FPI grant with reference PRE2018-084411. The authors wish to thank Renault SAS, especially P. Mallet and E. Gaiffas, for supporting this research.Payri, F.; Martín, J.; Arnau Martínez, FJ.; Artham, S. (2022). Analysis of temperature and altitude effects on the Global Energy Balance during WLTC. International Journal of Engine Research. 23(11):1831-1849. https://doi.org/10.1177/1468087421103429218311849231

Lumped Approach for Flow-Through and Wall-Flow Monolithic Reactors Modelling for Real-Time Automotive Applications

[EN] The increasingly restrictive legislation on pollutant emissions is involving new homologation procedures driven to be representative of real driving emissions. This context demands an update of the modelling tools leading to an accurate assessment of the engine and aftertreatment systems performance at the same time as these complex systems are understood as a single element. In addition, virtual engine models must retain the accuracy while reducing the computational effort to get closer to real-time computation. It makes them useful for pre-design and calibration but also potentially applicable to on-board diagnostics purposes. This paper responds to these requirements presenting a lumped modelling approach for the simulation of aftertreatment systems. The basic principles of operation of flow-through and wall-flow monoliths are covered leading the focus to the modelling of gaseous emissions conversion efficiency and particulate matter abatement, i.e. filtration and regeneration processes. The model concept is completed with the solution of pressure drop and heat transfer processes. The lumped approach hypotheses and the solution of the governing equations for every sub-model are detailed. While inertial pressure drop contributions are computed from the characteristic pressure drop coefficient, the porous medium effects in wall-flow monoliths are considered separately. Heat transfer sub-model applies a nodal approach to account for heat exchange and thermal inertia of the monolith substrate and the external canning. In wall-flow monoliths, the filtration and porous media properties are computed as a function of soot load applying a spherical packed bed approach. The soot oxidation mechanism including adsorption reactant phase is presented. Concerning gaseous emissions, the general scheme to solve the chemical species transport in the bulk gas and washcoat regions is also described. In particular, it is finally applied to the modelling of CO and HC abatement in a DOC and DPF brick. The model calibration steps against a set of steady-state in-engine experiments allowing separate certain phenomena are discussed. As a final step, the model performance is assessed against a transient test during which all modelled processes are taking place simultaneously under highly dynamic driving conditions. This test is simulated imposing different integration time-steps to demonstrate the model’s potential for real-time applications.This research has been partially supported by FEDER and the Government of Spain through project TRA2016-79185-R and by the European Union’s Horizon 2020 Framework Programme for research, technological development and demonstration under grant agreement number 723976.Payri, F.; Arnau Martínez, FJ.; Piqueras, P.; Ruiz Lucas, MJ. (2018). Lumped Approach for Flow-Through and Wall-Flow Monolithic Reactors Modelling for Real-Time Automotive Applications. SAE Technical Papers. https://doi.org/10.4271/2018-01-0954

Modeling and Evaluation of Oxy-Combustion and In Situ Oxygen Production in a Two-Stroke Marine Engine

[EN] Considering the concerns for emissions reduction in the maritime sector, the present paper evaluates, through modeling and simulation, oxy-fuel combustion in a two-stroke ship engine (2SE) and the best production system configuration to obtain the required oxygen (O2). An initial model of a ship engine is calibrated with the engine manufacturer's data and then adapted to work with O2 as the oxidant to eliminate nitrogen oxide (NOx) emissions and with exhaust gas recirculation (EGR) to control the in-cylinder combustion temperature. Mixed Ionic-Electronic Conducting (MIEC) membranes produce the necessary O2 from the ambient air, which is heated up and pressurized by a heat exchanger and turbocharging coupled system to provide the air conditions required for the proper operation of the MIEC. Several layouts of this system are evaluated for the full load engine operating point to find the optimum O2 production system configuration. Results reveal that the engine operating under oxy-fuel combustion conditions avoids NOx emissions at the expense of higher brake-specific fuel consumption (BSFC) to obtain the original brake torque, and also expels a stream composed exclusively of CO2 and H2O, which facilitates the separation of CO2 from exhaust gases.This research has been partially supported by Grant CIPROM/2021/061 funded by Generalitat Valenciana. Also partially supported by Grant PID2021-123351OB-I00 funded by MCIN/AEI/10.13039/501100011033 and, as appropriate, by ERDF A way of making Europe . And also partially funded by Programa de Ayudas de Investigación y Desarrollo PAID-01-22, from Universitat Politècnica de València (UPV) which granted the Rossana s pre-doctoral contract.Serrano, J.; Arnau Martínez, FJ.; Calvo, A.; Burgos, R. (2023). Modeling and Evaluation of Oxy-Combustion and In Situ Oxygen Production in a Two-Stroke Marine Engine. Applied Sciences. 13(18). https://doi.org/10.3390/app131810350131

Analysis of the energy balance during World harmonized Light vehicles Test Cycle in warmed and cold conditions using a Virtual Engine

This is the author's version of a work that was accepted for publication in International Journal of Engine Research. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published as https://doi.org/10.1177/1468087419878593.[EN] In recent years, the interests on transient operation and real driving emissions have increased because of the global concern about environmental pollution that has led to new emissions regulation and new standard testing cycles. In this framework, it is mandatory to focus the engines research on the transient operation, where a Virtual Engine has been used to perform the global energy balance of a 1.6-L diesel engine during a World harmonized Light vehicles Test Cycle. Thus, the energy repartition of the chemical energy has been described with warmed engine and cold start conditions, analyzing in detail the mechanisms affecting the engine consumption. The first analysis focuses on the ¿delay¿ effect affecting the instantaneous energy balance due to the time lag between the in-cylinder processes and pipes: as a main conclusion, it is obtained that it leads to an apparent unbalance than can reach more than 10% of the cumulated fuel energy at the beginning of the cycle, becoming later negligible. Energy split analysis in cold starting World harmonized Light vehicles Test Cycle shows that in this condition the energy accumulation in the block is a key term at the beginning (about 50%) that diminishes its weight until about 10% at the end of the cycle. In warmed conditions, energy accumulation is negligible, but the heat transfer to coolant and oil are higher than in cold starting conditions (21% vs 28%). The lower values of the mean brake efficiency at the beginning of the World harmonized Light vehicles Test Cycle (only about 20%) is affected, especially in cold starting, by the higher mechanical losses due to the higher oil viscosity and the heat rejection from the gases. The friction plays an important role only during the first half of the cycle, with a percentage of about 65% of the total mechanical losses and 10% of the total fuel energy at the end of the World harmonized Light vehicles Test Cycle. However, at the end of the cycle, it does not affect dramatically the mean brake efficiency which is about 31% both in cold starting and warmed World harmonized Light vehicles Test Cycle.The author(s) disclosed receipt of the following financial support for the research, authorship and/or publication of this article: This research has been partially funded by the European Union's Horizon 2020 Framework Programme for research, technological development and demonstration under grant agreement 723976 ("DiePeR'') and by the Spanish government under the grant agreement TRA2017-89894-R. The authors wish to thank Renault SAS, especially P. Mallet and E. Gaiffas, for supporting this research.Olmeda, P.; Martín, J.; Arnau Martínez, FJ.; Artham, S. (2020). Analysis of the energy balance during World harmonized Light vehicles Test Cycle in warmed and cold conditions using a Virtual Engine. International Journal of Engine Research. 21(6):1037-1054. https://doi.org/10.1177/1468087419878593S10371054216Tauzia, X., Maiboom, A., Karaky, H., & Chesse, P. (2018). Experimental analysis of the influence of coolant and oil temperature on combustion and emissions in an automotive diesel engine. International Journal of Engine Research, 20(2), 247-260. doi:10.1177/1468087417749391Payri, F., Olmeda, P., Martin, J., & Carreño, R. (2014). A New Tool to Perform Global Energy Balances in DI Diesel Engines. SAE International Journal of Engines, 7(1), 43-59. doi:10.4271/2014-01-0665Tauzia, X., & Maiboom, A. (2013). Experimental study of an automotive Diesel engine efficiency when running under stoichiometric conditions. Applied Energy, 105, 116-124. doi:10.1016/j.apenergy.2012.12.034Abedin, M. J., Masjuki, H. H., Kalam, M. A., Sanjid, A., Rahman, S. M. A., & Masum, B. M. (2013). Energy balance of internal combustion engines using alternative fuels. Renewable and Sustainable Energy Reviews, 26, 20-33. doi:10.1016/j.rser.2013.05.049Ajav, E. A., Singh, B., & Bhattacharya, T. K. (2000). Thermal balance of a single cylinder diesel engine operating on alternative fuels. Energy Conversion and Management, 41(14), 1533-1541. doi:10.1016/s0196-8904(99)00175-2DIMOPOULOS, P., BACH, C., SOLTIC, P., & BOULOUCHOS, K. (2008). Hydrogen–natural gas blends fuelling passenger car engines: Combustion, emissions and well-to-wheels assessment. International Journal of Hydrogen Energy, 33(23), 7224-7236. doi:10.1016/j.ijhydene.2008.07.012TAYMAZ, I. (2006). An experimental study of energy balance in low heat rejection diesel engine. Energy, 31(2-3), 364-371. doi:10.1016/j.energy.2005.02.004Olmeda, P., Martín, J., Novella, R., & Blanco-Cavero, D. (2018). Assessing the optimum combustion under constrained conditions. International Journal of Engine Research, 21(5), 811-823. doi:10.1177/1468087418814086Durgun, O., & Şahin, Z. (2009). Theoretical investigation of heat balance in direct injection (DI) diesel engines for neat diesel fuel and gasoline fumigation. Energy Conversion and Management, 50(1), 43-51. doi:10.1016/j.enconman.2008.09.007Jia, M., Gingrich, E., Wang, H., Li, Y., Ghandhi, J. B., & Reitz, R. D. (2015). Effect of combustion regime on in-cylinder heat transfer in internal combustion engines. International Journal of Engine Research, 17(3), 331-346. doi:10.1177/1468087415575647Jung, D., Yong, J., Choi, H., Song, H., & Min, K. (2013). Analysis of engine temperature and energy flow in diesel engine using engine thermal management. Journal of Mechanical Science and Technology, 27(2), 583-592. doi:10.1007/s12206-012-1235-4Caresana, F., Bilancia, M., & Bartolini, C. M. (2011). Numerical method for assessing the potential of smart engine thermal management: Application to a medium-upper segment passenger car. Applied Thermal Engineering, 31(16), 3559-3568. doi:10.1016/j.applthermaleng.2011.07.017Payri, F., López, J. J., Martín, J., & Carreño, R. (2018). Improvement and application of a methodology to perform the Global Energy Balance in internal combustion engines. Part 1: Global Energy Balance tool development and calibration. Energy, 152, 666-681. doi:10.1016/j.energy.2018.03.118Arrègle, J., López, J. J., Garcı́a, J. M., & Fenollosa, C. (2003). Development of a zero-dimensional Diesel combustion model. Applied Thermal Engineering, 23(11), 1319-1331. doi:10.1016/s1359-4311(03)00080-2Arrègle, J., López, J. J., Garcı́a, J. M., & Fenollosa, C. (2003). Development of a zero-dimensional Diesel combustion model. Part 1: Analysis of the quasi-steady diffusion combustion phase. Applied Thermal Engineering, 23(11), 1301-1317. doi:10.1016/s1359-4311(03)00079-6Benajes, J., Olmeda, P., Martín, J., & Carreño, R. (2014). A new methodology for uncertainties characterization in combustion diagnosis and thermodynamic modelling. Applied Thermal Engineering, 71(1), 389-399. doi:10.1016/j.applthermaleng.2014.07.010Payri, F., Olmeda, P., Martín, J., & Carreño, R. (2015). Experimental analysis of the global energy balance in a DI diesel engine. Applied Thermal Engineering, 89, 545-557. doi:10.1016/j.applthermaleng.2015.06.005Olmeda, P., Dolz, V., Arnau, F. J., & Reyes-Belmonte, M. A. (2013). Determination of heat flows inside turbochargers by means of a one dimensional lumped model. Mathematical and Computer Modelling, 57(7-8), 1847-1852. doi:10.1016/j.mcm.2011.11.078Torregrosa, A., Olmeda, P., Degraeuwe, B., & Reyes, M. (2006). A concise wall temperature model for DI Diesel engines. Applied Thermal Engineering, 26(11-12), 1320-1327. doi:10.1016/j.applthermaleng.2005.10.021Payri, R., Salvador, F. J., Gimeno, J., & Bracho, G. (2008). A NEW METHODOLOGY FOR CORRECTING THE SIGNAL CUMULATIVE PHENOMENON ON INJECTION RATE MEASUREMENTS. Experimental Techniques, 32(1), 46-49. doi:10.1111/j.1747-1567.2007.00188.xTormos, B., Martín, J., Carreño, R., & Ramírez, L. (2018). A general model to evaluate mechanical losses and auxiliary energy consumption in reciprocating internal combustion engines. Tribology International, 123, 161-179. doi:10.1016/j.triboint.2018.03.00

A holistic methodology to correct heat transfer and bearing friction losses from hot turbocharger maps in order to obtain adiabatic efficiency of the turbomachinery

This is the author¿s version of a work that was accepted for publication in International Journal of Engine Research. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published as https://doi.org/10.1177/1468087419834194[EN] Turbocharger performance maps provided by manufacturers are usually far from the assumption of reproducing the isentropic performance. The reason being, those maps are usually measured using a hot gas stand. The definition of the effective turbocharger efficiency maps include the mechanical losses and heat transfer that has occurred during the gas stand test for the turbine maps and only the heat transfer for the compressor maps. Thus, a turbocharger engine model that uses these maps provides accurate results only when simulating turbocharger operative conditions similar to those at which the maps are recorded. However, for some critical situations such as Worldwide harmonized Light vehicles Test Cycles (WLTC) driving cycle or off-design conditions, it is difficult to ensure this assumption. In this article, an internal and external heat transfer model combined with mechanical losses model, both previously developed and calibrated, has been used as an original tool to ascertain a calculation procedure to obtain adiabatic maps from diabatic standard turbocharger maps. The turbocharger working operative conditions at the time of map measurements and geometrical information of the turbocharger are necessary to discount both effects precisely. However, the maps from turbocharger manufacturers do not include all required information. These create additional challenges to develop the procedure to obtain approximated adiabatic maps making some assumptions based on SAE standards for non-available data. A sensitivity study has been included in this article to check the validity of the hypothesis proposed by changing the values of parameters which are not included in the map data. The proposed procedure becomes a valuable tool either for Original Equipment Manufacturers (OEMs) to parameterize turbocharger performance accurately for benchmarking and turbocharged engine design or to turbocharger manufacturers to provide much-appreciated information of their performance maps.The author(s) disclosed receipt of the following financial support for the research, authorship and/or publication of this article: This work has been partially supported by FEDER and the Government of Spain through Grant No. TRA2016-79185-R.Serrano, J.; Olmeda, P.; Arnau Martínez, FJ.; Samala, V. (2020). A holistic methodology to correct heat transfer and bearing friction losses from hot turbocharger maps in order to obtain adiabatic efficiency of the turbomachinery. International Journal of Engine Research. 21(8):1314-1335. https://doi.org/10.1177/1468087419834194S13141335218Sirakov, B., & Casey, M. (2012). Evaluation of Heat Transfer Effects on Turbocharger Performance. Journal of Turbomachinery, 135(2). doi:10.1115/1.4006608Payri, F., Serrano, J. R., Fajardo, P., Reyes-Belmonte, M. A., & Gozalbo-Belles, R. (2012). A physically based methodology to extrapolate performance maps of radial turbines. Energy Conversion and Management, 55, 149-163. doi:10.1016/j.enconman.2011.11.003Chesse, P., Chalet, D., & Tauzia, X. (2011). Impact of the Heat Transfer on the Performance Calculations of Automotive Turbocharger Compressor. Oil & Gas Science and Technology – Revue d’IFP Energies nouvelles, 66(5), 791-800. doi:10.2516/ogst/2011129Serrano, J. R., Olmeda, P., Arnau, F. J., Reyes-Belmonte, M. A., & Tartoussi, H. (2015). A study on the internal convection in small turbochargers. Proposal of heat transfer convective coefficients. Applied Thermal Engineering, 89, 587-599. doi:10.1016/j.applthermaleng.2015.06.053Tanda, G., Marelli, S., Marmorato, G., & Capobianco, M. (2017). An experimental investigation of internal heat transfer in an automotive turbocharger compressor. Applied Energy, 193, 531-539. doi:10.1016/j.apenergy.2017.02.053Serrano, J., Olmeda, P., Arnau, F., & Dombrovsky, A. (2014). General Procedure for the Determination of Heat Transfer Properties in Small Automotive Turbochargers. SAE International Journal of Engines, 8(1), 30-41. doi:10.4271/2014-01-2857Payri, F., Olmeda, P., Arnau, F. J., Dombrovsky, A., & Smith, L. (2014). External heat losses in small turbochargers: Model and experiments. Energy, 71, 534-546. doi:10.1016/j.energy.2014.04.096Serrano, J. R., Olmeda, P., Tiseira, A., García-Cuevas, L. M., & Lefebvre, A. (2013). Theoretical and experimental study of mechanical losses in automotive turbochargers. Energy, 55, 888-898. doi:10.1016/j.energy.2013.04.042SAE International. Turbocharger gas stand test code, SAE J1826. Technical Report, Society of Automotive Engineers Inc, Warrendale, PA, 1995.SAE International. Supercharger testing standard, SAE J1723. Technical Report, Society of Automotive Engineers Inc, Warrendale, PA, 1995.Serrano, J. R., Olmeda, P., Páez, A., & Vidal, F. (2010). An experimental procedure to determine heat transfer properties of turbochargers. Measurement Science and Technology, 21(3), 035109. doi:10.1088/0957-0233/21/3/03510

On-Engine Measurement of Turbocharger Surge Limit

In this article a new experimental technique is presented to measure the turbocharger surge limit in a regular engine test bench. It is known that the surge margin on engine tests may be very different from that obtained in a steady-flow gas-stand. In particular, surge is very dependent on the flow pattern produced by the compressor inlet duct and also on the piping upstream and downstream the compressor. The proposed technique that is based on the injection of pressurized air into the intake manifold is compared with the other ways of measuring the compressor map on engine. Some results with different compressor arrangements are presented and discussed. It is demonstrated that this technique allows for measuring not only the actual surge line but also the complete compressor performance map.This work has been funded by Spain's Ministerio de Ciencia y Tecnologia through project TRA2007-65433. The authors acknowledge R. Lujan for his valuable contribution to the tests. RL is indebted to the Generalidad Valenciana through the grant GRISOLIA/2008/009.Galindo, J.; Tiseira Izaguirre, AO.; Arnau Martínez, FJ.; Lang, RH. (2013). On-Engine Measurement of Turbocharger Surge Limit. Experimental Techniques. 37(1):47-54. https://doi.org/10.1111/j.1747-1567.2010.00697.xS4754371Hajilouy-Benisi, A., Rad, M., & Shahhosseini, M. R. (2009). EMPIRICAL ASSESSMENT OF THE PERFORMANCE CHARACTERISTICS IN TURBOCHARGER TURBINE AND COMPRESSOR. Experimental Techniques, 34(3), 54-67. doi:10.1111/j.1747-1567.2009.00542.xGalindo, J., Serrano, J. R., Guardiola, C., & Cervelló, C. (2006). Surge limit definition in a specific test bench for the characterization of automotive turbochargers. Experimental Thermal and Fluid Science, 30(5), 449-462. doi:10.1016/j.expthermflusci.2005.06.002Oakes, W. C., Lawless, P. B., Fagan, J. R., & Fleeter, S. (2002). High-Speed Centrifugal Compressor Surge Initiation Characterization. Journal of Propulsion and Power, 18(5), 1012-1018. doi:10.2514/2.6049Galindo, J., Serrano, J. R., Climent, H., & Tiseira, A. (2008). Experiments and modelling of surge in small centrifugal compressor for automotive engines. Experimental Thermal and Fluid Science, 32(3), 818-826. doi:10.1016/j.expthermflusci.2007.10.001Fink, D. A., Cumpsty, N. A., & Greitzer, E. M. (1992). Surge Dynamics in a Free-Spool Centrifugal Compressor System. Journal of Turbomachinery, 114(2), 321-332. doi:10.1115/1.2929146Greitzer, E. M. (1976). Surge and Rotating Stall in Axial Flow Compressors—Part II: Experimental Results and Comparison With Theory. Journal of Engineering for Power, 98(2), 199. doi:10.1115/1.3446139Gravdahl, J. T., & Egeland, O. (1999). Centrifugal compressor surge and speed control. IEEE Transactions on Control Systems Technology, 7(5), 567-579. doi:10.1109/87.784420Kurz, R., & White, R. C. (2004). Surge Avoidance in Gas Compression Systems. Journal of Turbomachinery, 126(4), 501-506. doi:10.1115/1.1777577Engeda, A., Kim, Y., Aungier, R., & Direnzi, G. (2003). The Inlet Flow Structure of a Centrifugal Compressor Stage and Its Influence on the Compressor Performance. Journal of Fluids Engineering, 125(5), 779-785. doi:10.1115/1.1601255Galindo, J., Serrano, J. R., Margot, X., Tiseira, A., Schorn, N., & Kindl, H. (2007). Potential of flow pre-whirl at the compressor inlet of automotive engine turbochargers to enlarge surge margin and overcome packaging limitations. International Journal of Heat and Fluid Flow, 28(3), 374-387. doi:10.1016/j.ijheatfluidflow.2006.06.002Galindo, J., Climent, H., Guardiola, C., & Tiseira, A. (2009). On the effect of pulsating flow on surge margin of small centrifugal compressors for automotive engines. Experimental Thermal and Fluid Science, 33(8), 1163-1171. doi:10.1016/j.expthermflusci.2009.07.006Payri, F., Galindo, J., Climent, H., & Guardiola, C. (2005). MEASUREMENT OF THE OIL CONSUMPTION OF AN AUTOMOTIVE TURBOCHARGER. Experimental Techniques, 29(5), 25-27. doi:10.1111/j.1747-1567.2005.tb00236.xHellstrom , F. Guillou , E. Gancedo , M. et al. Stall Development in a Ported Shroud Compressor Using PIV Measurements and Large Eddy Simulation SAE Paper 2010 10.4271/2010-01-018

Development of a Variable Valve Actuation Control to Improve Diesel Oxidation Catalyst Efficiency and Emissions in a Light Duty Diesel Engine

[EN] Growing interest has arisen to adopt Variable Valve Timing (VVT) technology for automotive engines due to the need to fulfill the pollutant emission regulations. Several VVT strategies, such as the exhaust re-opening and the late exhaust closing, can be used to achieve an increment in the after-treatment upstream temperature by increasing the residual gas amount. In this study, a one-dimensional gas dynamics engine model has been used to simulate several VVT strategies and develop a control system to actuate over the valves timing in order to increase diesel oxidation catalyst efficiency and reduce the exhaust pollutant emissions. A transient operating conditions comparison, taking the Worldwide Harmonized Light-Duty Vehicles Test Cycle (WLTC) as a reference, has been done by analyzing fuel economy, HC and CO pollutant emissions levels. The results conclude that the combination of an early exhaust and a late intake valve events leads to a 20% reduction in CO emissions with a fuel penalty of 6% over the low speed stage of the WLTC, during the warm-up of the oxidation catalyst. The same set-up is able to reduce HC emissions down to 16% and NO(x)emission by 13%.This research has been partially funded by the Spanish government under the grant agreement TRA2017-89894-R ("Mecoem"). Angel Aunon was supported through the "Apoyo para la investigacion y Desarrollo (PAID)" grant for doctoral studies (FPI S2 2018 1048) by Universitat Politecnica de Valencia.Serrano, J.; Arnau Martínez, FJ.; Martín, J.; Auñón-García, Á. (2020). Development of a Variable Valve Actuation Control to Improve Diesel Oxidation Catalyst Efficiency and Emissions in a Light Duty Diesel Engine. Energies. 13(17):1-26. https://doi.org/10.3390/en13174561S1261317Arnau, F. J., Martín, J., Pla, B., & Auñón, Á. (2020). Diesel engine optimization and exhaust thermal management by means of variable valve train strategies. International Journal of Engine Research, 22(4), 1196-1213. doi:10.1177/1468087419894804Luján, J. M., Serrano, J. R., Piqueras, P., & García-Afonso, Ó. (2015). Experimental assessment of a pre-turbo aftertreatment configuration in a single stage turbocharged diesel engine. Part 2: Transient operation. Energy, 80, 614-627. doi:10.1016/j.energy.2014.12.017Lancefield, T., Methley, I., Räse, U., & Kuhn, T. (2000). The Application of Variable Event Valve Timing to a Modern Diesel Engine. SAE Technical Paper Series. doi:10.4271/2000-01-1229Gonzalez D, M. A., & Di Nunno, D. (2016). Internal Exhaust Gas Recirculation for Efficiency and Emissions in a 4-Cylinder Diesel Engine. SAE Technical Paper Series. doi:10.4271/2016-01-2184Serrano, J. R., Piqueras, P., Navarro, R., Gómez, J., Michel, M., & Thomas, B. (2016). Modelling Analysis of Aftertreatment Inlet Temperature Dependence on Exhaust Valve and Ports Design Parameters. SAE Technical Paper Series. doi:10.4271/2016-01-0670Siewert, R. M. (1971). How Individual Valve Timing Events Affect Exhaust Emissions. SAE Technical Paper Series. doi:10.4271/710609Tomoda, T., Ogawa, T., Ohki, H., Kogo, T., Nakatani, K., & Hashimoto, E. (2010). Improvement of Diesel Engine Performance by Variable Valve Train System. International Journal of Engine Research, 11(5), 331-344. doi:10.1243/14680874jer586Benajes, J., Reyes, E., & Luján, J. M. (1996). Modelling Study of the Scavenging Process in a Turbocharged Diesel Engine with Modified Valve Operation. Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science, 210(4), 383-393. doi:10.1243/pime_proc_1996_210_210_02Deppenkemper, K., Özyalcin, C., Ehrly, M., Schoenen, M., Bergmann, D., & Pischinger, S. (2018). 1D Engine Simulation Approach for Optimizing Engine and Exhaust Aftertreatment Thermal Management for Passenger Car Diesel Engines by Means of Variable Valve Train (VVT) Applications. SAE Technical Paper Series. doi:10.4271/2018-01-0163Zammit, J. P., McGhee, M. J., Shayler, P. J., Law, T., & Pegg, I. (2015). The effects of early inlet valve closing and cylinder disablement on fuel economy and emissions of a direct injection diesel engine. Energy, 79, 100-110. doi:10.1016/j.energy.2014.10.065Pan, X., Zhao, Y., Lou, D., & Fang, L. (2020). Study of the Miller Cycle on a Turbocharged DI Gasoline Engine Regarding Fuel Economy Improvement at Part Load. Energies, 13(6), 1500. doi:10.3390/en13061500Guan, W., Pedrozo, V. B., Zhao, H., Ban, Z., & Lin, T. (2019). Variable valve actuation–based combustion control strategies for efficiency improvement and emissions control in a heavy-duty diesel engine. International Journal of Engine Research, 21(4), 578-591. doi:10.1177/1468087419846031Guan, W., Zhao, H., Ban, Z., & Lin, T. (2018). Exploring alternative combustion control strategies for low-load exhaust gas temperature management of a heavy-duty diesel engine. International Journal of Engine Research, 20(4), 381-392. doi:10.1177/1468087418755586Maniatis, P., Wagner, U., & Koch, T. (2018). A model-based and experimental approach for the determination of suitable variable valve timings for cold start in partial load operation of a passenger car single-cylinder diesel engine. International Journal of Engine Research, 20(1), 141-154. doi:10.1177/1468087418817119Kim, J., & Bae, C. (2015). An investigation on the effects of late intake valve closing and exhaust gas recirculation in a single-cylinder research diesel engine in the low-load condition. Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering, 230(6), 771-787. doi:10.1177/0954407015595149Zhou, X., Liu, E., Sun, D., & Su, W. (2018). Study on transient emission spikes reduction of a heavy-duty diesel engine equipped with a variable intake valve closing timing mechanism and a two-stage turbocharger. International Journal of Engine Research, 20(3), 277-291. doi:10.1177/1468087417748837Gosala, D. B., Ramesh, A. K., Allen, C. M., Joshi, M. C., Taylor, A. H., Van Voorhis, M., … Stretch, D. (2017). Diesel engine aftertreatment warm-up through early exhaust valve opening and internal exhaust gas recirculation during idle operation. International Journal of Engine Research, 19(7), 758-773. doi:10.1177/1468087417730240Parvate-Patil, G. B., Hong, H., & Gordon, B. (2004). Analysis of Variable Valve Timing Events and Their Effects on Single Cylinder Diesel Engine. SAE Technical Paper Series. doi:10.4271/2004-01-2965Piano, A., Millo, F., Di Nunno, D., & Gallone, A. (2017). Numerical Analysis on the Potential of Different Variable Valve Actuation Strategies on a Light Duty Diesel Engine for Improving Exhaust System Warm Up. SAE Technical Paper Series. doi:10.4271/2017-24-0024Payri, F., Arnau, F. J., Piqueras, P., & Ruiz, M. J. (2018). Lumped Approach for Flow-Through and Wall-Flow Monolithic Reactors Modelling for Real-Time Automotive Applications. SAE Technical Paper Series. doi:10.4271/2018-01-0954Martin, J., Arnau, F., Piqueras, P., & Auñon, A. (2018). Development of an Integrated Virtual Engine Model to Simulate New Standard Testing Cycles. SAE Technical Paper Series. doi:10.4271/2018-01-1413Serrano, J. R., Arnau, F. J., García-Cuevas, L. M., Dombrovsky, A., & Tartoussi, H. (2016). Development and validation of a radial turbine efficiency and mass flow model at design and off-design conditions. Energy Conversion and Management, 128, 281-293. doi:10.1016/j.enconman.2016.09.032Galindo, J., Tiseira, A., Navarro, R., Tarí, D., Tartoussi, H., & Guilain, S. (2016). Compressor Efficiency Extrapolation for 0D-1D Engine Simulations. SAE Technical Paper Series. doi:10.4271/2016-01-0554Serrano, J. R., Olmeda, P., Arnau, F. J., & Samala, V. (2019). A holistic methodology to correct heat transfer and bearing friction losses from hot turbocharger maps in order to obtain adiabatic efficiency of the turbomachinery. International Journal of Engine Research, 21(8), 1314-1335. doi:10.1177/1468087419834194Serrano, 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.2015.03.130Arrègle, J., López, J. J., Martín, J., & Mocholí, E. M. (2006). Development of a Mixing and Combustion Zero-Dimensional Model for Diesel Engines. SAE Technical Paper Series. doi:10.4271/2006-01-1382Payri, F., Arrègle, J., López, J. J., & Mocholí, E. (2008). Diesel NOx Modeling with a Reduction Mechanism for the Initial NOx Coming from EGR or Re-entrained Burned Gases. SAE Technical Paper Series. doi:10.4271/2008-01-1188Broatch, A., Olmeda, P., Martin, J., & Salvador-Iborra, J. (2018). Development and Validation of a Submodel for Thermal Exchanges in the Hydraulic Circuits of a Global Engine Model. SAE Technical Paper Series. doi:10.4271/2018-01-0160Guardiola, C., Pla, B., Bares, P., & Mora, J. (2018). An on-board method to estimate the light-off temperature of diesel oxidation catalysts. International Journal of Engine Research, 21(8), 1480-1492. doi:10.1177/1468087418817965Russell, A., & Epling, W. S. (2011). Diesel Oxidation Catalysts. Catalysis Reviews, 53(4), 337-423. doi:10.1080/01614940.2011.596429Guardiola, C., Pla, B., Piqueras, P., Mora, J., & Lefebvre, D. (2017). Model-based passive and active diagnostics strategies for diesel oxidation catalysts. Applied Thermal Engineering, 110, 962-971. doi:10.1016/j.applthermaleng.2016.08.207Abdelghaffar, W. A., Osman, M. M., Saeed, M. N., & Abdelfatteh, A. I. (2002). Effects of Coolant Temperature on the Performance and Emissions of a Diesel Engine. Design, Operation, and Application of Modern Internal Combustion Engines and Associated Systems. doi:10.1115/ices2002-464Torregrosa, A. J., Olmeda, P., Martín, J., & Degraeuwe, B. (2006). Experiments on the influence of inlet charge and coolant temperature on performance and emissions of a DI Diesel engine. Experimental Thermal and Fluid Science, 30(7), 633-641. doi:10.1016/j.expthermflusci.2006.01.00

Design of a carbon capture system for oxy-fuel combustion in compression ignition engines with exhaust water recirculation

[EN] The oxy-fuel combustion engine concept with onboard oxygen generation and carbon capture (CC) is studied using as a starting point a baseline oxy-fuel combustion layout coupled to a mixed ionic-electronic conducting membranes for producing oxygen (O2) from the air. A CC system is designed accounting for the flash-out temperatures and the operating pressure of the last CO2 purification step. The proposed engine concept is optimized through the product of useful effective efficiency and engine brake power,which is maximized actuating on the start of injection (SOI) for every assessed gas path layouts. The additional cooling power required by the carbon capture system (CC) is also contemplated . Initially, two approaches are compared when the CC is coupled to the O2 generation unit, including or not an intake cooler. The use of intake cooler yields better engine performance than removing it but increases the cooling power requirements significantly. The extreme results from using or not the intake cooler, indicates that a proper solution could combine both cases, approaching for a different cooling concept. A mixer model is developed to recirculate part of the water condensed in the CC towards the cylinder inlet to lower the intake gas temperature and increase the oxidizer heat capacity ratio. From this layout, an optimum setup for SOI and recirculated water mass flow is found considering the trade-off between additional cooling power and engine performance. Indeed, this case reduces the total ICE additional cooling power required by the exclusive use of an intake cooler by about 27% and improves the engine performance by about 20% in comparison to the lack of intake cooling of the charge flow.This work has been partially supported by Grant PID2021-123351OB-I00 funded by MCIN/AEI/10.13039/501100011033 and, as appropriate, by "ERDF A way of making Europe". In addition, the work has been supported by Grant CIPROM/2021/061 funded by Generalitat Valenciana, Spain. Finally, the Ph.D. candidate Vitor Farias has been funded by Generalitat Valenciana, Spain (GRISOLIAP/2020/078) .Luján, JM.; Arnau Martínez, FJ.; Piqueras, P.; Farias-Da Silva, VH. (2023). Design of a carbon capture system for oxy-fuel combustion in compression ignition engines with exhaust water recirculation. Energy Conversion and Management. 284:1-19. https://doi.org/10.1016/j.enconman.2023.11697911928

Experimental validation of a quasi-two-dimensional radial turbine model

[EN] This article presents the experimental validation of a quasi-two-dimensional radial turbine model able to be used in turbocharged reciprocating internal combustion engine simulations. A passenger car variable-geometry turbine has been tested under steady and pulsating flow conditions, instrumented with multiple pressure probes, temperature sensors and mass flow sensors. Using the data obtained, a pressure decomposition has been performed. The pressure at the turbine inlet and outlet has been split into forward and backward travelling waves, employing the reflected and transmitted waves to verify the goodness of the model. The experimental results have been used to compare the quasi-two-dimensional radial turbine model as well as a classic one-dimensional model. The quasi-two-dimensional code presents a good degree of correlation with the experimental results, providing better results than the one-dimensional approach, especially when studying the high-frequency spectrum.Pablo Soler is partially supported through contract FPI-2017-S2-1428 of Programa de Apoyo para la Investigación y Desarrollo (PAID) of Universitat Politècnica de València. The authors of this paper wish to thank M.A. Ortiz and V. Ucedo for their invaluable work during the experimental setup and the campaign.Galindo, J.; Arnau Martínez, FJ.; García-Cuevas González, LM.; Soler-Blanco, P. (2018). Experimental validation of a quasi-two-dimensional radial turbine model. International Journal of Engine Research. https://doi.org/10.1177/1468087418788502SKesgin, U. (2005). Effect of turbocharging system on the performance of a natural gas engine. Energy Conversion and Management, 46(1), 11-32. doi:10.1016/j.enconman.2004.02.006Tang, H., Pennycott, A., Akehurst, S., & Brace, C. J. (2014). A review of the application of variable geometry turbines to the downsized gasoline engine. International Journal of Engine Research, 16(6), 810-825. doi:10.1177/1468087414552289Pesiridis, A. (2012). The application of active control for turbocharger turbines. International Journal of Engine Research, 13(4), 385-398. doi:10.1177/1468087411435205Romagnoli, A., & Martinez-Botas, R. (2011). Performance prediction of a nozzled and nozzleless mixed-flow turbine in steady conditions. International Journal of Mechanical Sciences, 53(8), 557-574. doi:10.1016/j.ijmecsci.2011.05.003Payri, F., Serrano, J. R., Fajardo, P., Reyes-Belmonte, M. A., & Gozalbo-Belles, R. (2012). A physically based methodology to extrapolate performance maps of radial turbines. Energy Conversion and Management, 55, 149-163. doi:10.1016/j.enconman.2011.11.003Costall, A. W., McDavid, R. M., Martinez-Botas, R. F., & Baines, N. C. (2010). Pulse Performance Modeling of a Twin Entry Turbocharger Turbine Under Full and Unequal Admission. Journal of Turbomachinery, 133(2). doi:10.1115/1.4000566De Bellis, V., & Marelli, S. (2015). One-dimensional simulations and experimental analysis of a wastegated turbine for automotive engines under unsteady flow conditions. Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering, 229(13), 1801-1816. doi:10.1177/0954407015571672Serrano, J. R., Olmeda, P., Páez, A., & Vidal, F. (2010). An experimental procedure to determine heat transfer properties of turbochargers. Measurement Science and Technology, 21(3), 035109. doi:10.1088/0957-0233/21/3/035109Burke, R. D., Copeland, C. D., Duda, T., & Rayes-Belmote, M. A. (2016). Lumped Capacitance and Three-Dimensional Computational Fluid Dynamics Conjugate Heat Transfer Modeling of an Automotive Turbocharger. Journal of Engineering for Gas Turbines and Power, 138(9). doi:10.1115/1.4032663Olmeda, P., Dolz, V., Arnau, F. J., & Reyes-Belmonte, M. A. (2013). Determination of heat flows inside turbochargers by means of a one dimensional lumped model. Mathematical and Computer Modelling, 57(7-8), 1847-1852. doi:10.1016/j.mcm.2011.11.078Serrano, J., Olmeda, P., Arnau, F., Reyes-Belmonte, M., & Lefebvre, A. (2013). Importance of Heat Transfer Phenomena in Small Turbochargers for Passenger Car Applications. SAE International Journal of Engines, 6(2), 716-728. doi:10.4271/2013-01-0576Aghaali, H., Ångström, H.-E., & Serrano, J. R. (2014). Evaluation of different heat transfer conditions on an automotive turbocharger. International Journal of Engine Research, 16(2), 137-151. doi:10.1177/1468087414524755Serrano, J. R., Olmeda, P., Tiseira, A., García-Cuevas, L. M., & Lefebvre, A. (2013). Theoretical and experimental study of mechanical losses in automotive turbochargers. Energy, 55, 888-898. doi:10.1016/j.energy.2013.04.042Serrano, J. R., Olmeda, P., Tiseira, A., García-Cuevas, L. M., & Lefebvre, A. (2013). Importance of Mechanical Losses Modeling in the Performance Prediction of Radial Turbochargers under Pulsating Flow Conditions. SAE International Journal of Engines, 6(2), 729-738. doi:10.4271/2013-01-0577Galindo, J., Fajardo, P., Navarro, R., & García-Cuevas, L. M. (2013). Characterization of a radial turbocharger turbine in pulsating flow by means of CFD and its application to engine modeling. Applied Energy, 103, 116-127. doi:10.1016/j.apenergy.2012.09.013Hakeem, I., Su, C.-C., Costall, A., & Martinez-Botas, R. F. (2007). Effect of volute geometry on the steady and unsteady performance of mixed-flow turbines. Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy, 221(4), 535-549. doi:10.1243/09576509jpe314Hu X. An advanced turbocharger model for the internal combustion engine. PhD Thesis, Purdue University, West Lafayette, IN, 2000.King A. A turbocharger unsteady performance model for the GT-power internal combustion engine simulation. PhD Thesis, Purdue University, West Lafayette, IN, 2000.Rajoo, S., & Martinez-Botas, R. (2008). Variable Geometry Mixed Flow Turbine for Turbochargers: An Experimental Study. International Journal of Fluid Machinery and Systems, 1(1), 155-168. doi:10.5293/ijfms.2008.1.1.155Serrano, 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.2017.02.118Torregrosa, A. J., Broatch, A., Navarro, R., & García-Tíscar, J. (2014). Acoustic characterization of automotive turbocompressors. International Journal of Engine Research, 16(1), 31-37. doi:10.1177/1468087414562866Leufvén, O., & Eriksson, L. (2014). Measurement, analysis and modeling of centrifugal compressor flow for low pressure ratios. International Journal of Engine Research, 17(2), 153-168. doi:10.1177/1468087414562456Galindo, J., Tiseira, A., Navarro, R., Tarí, D., & Meano, C. M. (2017). Effect of the inlet geometry on performance, surge margin and noise emission of an automotive turbocharger compressor. Applied Thermal Engineering, 110, 875-882. doi:10.1016/j.applthermaleng.2016.08.099Galindo, J., Tiseira, A., Fajardo, P., & García-Cuevas, L. M. (2014). Development and validation of a radial variable geometry turbine model for transient pulsating flow applications. Energy Conversion and Management, 85, 190-203. doi:10.1016/j.enconman.2014.05.072Ding, Z., Zhuge, W., Zhang, Y., Chen, H., Martinez-Botas, R., & Yang, M. (2017). A one-dimensional unsteady performance model for turbocharger turbines. Energy, 132, 341-355. doi:10.1016/j.energy.2017.04.154Toro, E. F., Spruce, M., & Speares, W. (1994). Restoration of the contact surface in the HLL-Riemann solver. 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Energy Conversion and Management, 128, 281-293. doi:10.1016/j.enconman.2016.09.032Serrano, J. R., Arnau, F. J., Dolz, V., Tiseira, A., & Cervelló, C. (2008). A model of turbocharger radial turbines appropriate to be used in zero- and one-dimensional gas dynamics codes for internal combustion engines modelling. Energy Conversion and Management, 49(12), 3729-3745. doi:10.1016/j.enconman.2008.06.031Piñero, G., Vergara, L., Desantes, J. M., & Broatch, A. (2000). Estimation of velocity fluctuation in internal combustion engine exhaust systems through beamforming techniques. Measurement Science and Technology, 11(11), 1585-1595. doi:10.1088/0957-0233/11/11/307Harris, F. J. (1978). On the use of windows for harmonic analysis with the discrete Fourier transform. Proceedings of the IEEE, 66(1), 51-83. doi:10.1109/proc.1978.1083

Diesel engine optimization and exhaust thermal management by means of variable valve train strategies

[EN] Due to the need to achieve a fast warm-up of the after-treatment system in order to fulfill the pollutant emission regulations, a growing interest has arisen to adopt variable valve timing technology for automotive engines. Several variable valve timing strategies can be used to achieve an increment in the after-treatment upstream temperature by increasing the residual gas amount. In this study, a one-dimensional gas dynamics engine model has been used to carry out a simulation study comparing several exhaust variable valve actuation strategies. A steady-state analysis has been done in order to evaluate the potential of the different strategies at different operating points. Finally, the effect on the after-treatment warm-up, fuel economy and pollutant emission levels was evaluated over the worldwide harmonized light vehicles test cycle. As a conclusion, the combination of an advanced exhaust (early exhaust valve opening and early exhaust valve closing) and a delayed intake (late intake valve opening and late intake valve closing) presented the best trade-off between exhaust temperature increment and fuel consumption, which achieved a mean temperature increment during low-speed phase of the worldwide harmonized light vehicles test cycle of 27¿°C with a fuel penalty of 6%. The exhaust valve re-opening technique offers a worse trade-off. However, the exhaust valve re-opening leads to lower nitrogen oxide (29% less) and carbon monoxide (11% less) pollutant emissions.The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This research has been partially funded by the European Union's Horizon 2020 Framework Programme for research, technological development and demonstration under grant agreement 723976 ("DiePeR") and by the Spanish government under the grant agreement TRA2017-89894-R. The authors want to acknowledge the "Apoyo para la investigacion y Desarrollo (PAID)," grant for doctoral studies (FPI S2 2018 1048), of Universitat Politecnica de Valencia.Arnau Martínez, FJ.; Martín, J.; Pla Moreno, B.; Auñón-García, Á. (2021). Diesel engine optimization and exhaust thermal management by means of variable valve train strategies. International Journal of Engine Research. 22(4):1196-1213. https://doi.org/10.1177/1468087419894804S1196121322