Publications
243 results found
Chiong MS, Rajoo S, Costall AW, et al., 2013, ASSESSMENT OF CYCLE AVERAGED TURBOCHARGER MAPS THROUGH ONE DIMENSIONAL AND MEAN-LINE COUPLED CODES, ASME Turbo Expo: Turbine Technical Conference and Exposition, Publisher: AMER SOC MECHANICAL ENGINEERS
- Author Web Link
- Cite
- Citations: 4
Cicciotti M, Geist S, Schild A, et al., 2013, Systematic one zone meanline modelling of centrifugal compressors for industrial online applications, ASME Turbo Expo 2013, San Antonio, Texas, June 3-7 2013, paper GT2013/95821
For developing model-based online applications such as condition monitoring and condition-based maintenance or real-time optimization, highly representative and yet simple physical models of centrifugal compressors are necessary. Previous investigations have shown that in this context meanline models represent a valid alternative to the commonly used empirical based modelling methodologies such as polynomial regression models or artificial neural networks. This paper provides a methodology for tailoring meanline models to multistage centrifugal compressors by appropriate selection and adaptation of loss correlations. Guidelines for the selection of the boundary conditions are also provided. The potential of the methodology is demonstrated in the Proof-of-concept section using two sets of data obtained from an air multistage centrifugal compressor operated in BASF SE, Ludwigshafen, Germany. The first set of data was used to calibrate the model whereas the second one was used for validation. The model results show that the predictions of stagnation temperature and pressure at the outlet of the stage deviate from the measurements respectively 0.15-3% and of 0.66-1.1% respectively. The results are discussed in the current paper. Copyright © 2013 by ASME.
Cao T, Xu L, Yang M, et al., 2013, RADIAL TURBINE ROTOR RESPONSE TO PULSATING INLET FLOWS, ASME Turbo Expo: Turbine Technical Conference and Exposition, Publisher: AMER SOC MECHANICAL ENGINEERS
- Author Web Link
- Cite
- Citations: 5
Newton P, Romagnoli A, Martinez-Botas R, et al., 2013, A METHOD OF MAP EXTRAPOLATION FOR UNEQUAL AND PARTIAL ADMISSION IN A DOUBLE ENTRY TURBINE, ASME Turbo Expo: Turbine Technical Conference and Exposition, Publisher: AMER SOC MECHANICAL ENGINEERS
- Author Web Link
- Cite
- Citations: 2
Yang M, Martinez-Botas R, Zhang Y, 2013, Inlet Duct Treatment for Stability Improvement on a High Pressure Ratio Centrifugal Compressor, ASME Turbo Expo: Turbine Technical Conference and Exposition, Publisher: AMER SOC MECHANICAL ENGINEERS
- Author Web Link
- Cite
- Citations: 1
von Srbik MT, Martinez-Botas R, 2012, Vehicle Optimisation for Regenerative Brake Energy Maximisation, IMechE Sustainable Vehicles Technologies Conference
Regenerative braking is an effective method to increase the driving range of Hybrid Electric Vehicles (HEV) and to reduce overall vehicle fuel consumption. This paper presents the potential savings due to regenerative braking and the resulting driving range extension. A Cooperative Regenerative Braking Strategy (CRBS) Matlab/Simulink environment has been developed. The regenerative energy and efficiency are evaluated for given driving cycle time-trace and vehicle component configuration in a flexible simulation platform architecture containing reduced-order component models.The paper focuses on vehicle configuration comparison and quantification including economic considerations. A sensitivity study yielded the isolated dependency of regeneration efficiency performance on several parameters, in decreasing order of impact: electric machine efficiency, drive type, power train configuration, brake torque application, shifting strategy, air resistance and vehicle mass. The resulting significance to improvements of the overall vehicle includes the likelihood of advances in the respective technologies.Optimum configurations for specific vehicle types and driving scenarios have been devised and potential savings due to CRBS implementation quantified; pointing towards the great significance of vehicle configuration optimisation for a particular application rather than the broadest customer base possible.Future projections in terms of Carbon Dioxide emission reduction due to regenerative braking and component optimisation (up to 40%) were made. The likelihood of technology advances and acceleration of innovation market diffusion following consumption trends were taken into account.Barriers to quick market implementation were explored, including initial capital investment, consumer reluctance to change, and marketing difficulties. Future development challenges in the Hybrid vehicle industry are discussed.
Malloy AC, Martinez-Botas RF, Jaensch M, et al., 2012, Measurement of heat generation rate in the permanent magnets of rotating electrical machines
This paper presents an experimental method for measuring heat generation rate in the permanent magnets of rotating electrical machines. The results obtained from the experimental work are used to derive an empirical correlation which is subsequently used to predict the total thermal energy stored in a magnet after a speed varying torque load. The results of an uncertainty analysis are offered in order to show the usefulness of the technique. An axial flux permanent magnet machine has been used as a case study in this work, though the methodology could certainly be applied to other topologies.
Chiong MS, Rajoo S, Romagnoli A, et al., 2012, Single entry mixed flow turbine performance prediction with 1-D gas dynamic code coupled with mean line model, International Journal of Gas Turbine, Propulsion and Power Systems, Vol: 4, Pages: 8-16
It is a well known fact that turbocharger works with pulsating exhaust flow in its entire operating life, hence the need to predict unsteady performance. This paper presents the unsteady performance prediction resultof a single entry nozzleless mixed flow turbine under steady flow and 60 Hz pulsating flow at 43.0 rps/ √ K operating speed. The modeling method coupled one-dimensional gas dynamic modelwith a mean-line model to predict the turbine efficiency by appropriate losses consideration. The coupled method assumes that the turbine volute has a large volume and length, so that unsteadiness effect of the pulsating flow is significant while the rotor is assumed to behave quasisteadily. A pressure drop boundary is used to simulate pressure drop across the turbine volute. The coupled method was validated with the experimentally measured steady state results of the same turbine. Experimentally measured total conditions of the flow were used as inlet conditions for the model during unsteady analysis. The predicted isentropic power averaged results show convincing match with the experimental data. This will set forward a systematic approach for engine designers to evaluate turbine performance beyond what will be normally provided by turbocharger manufacturers, which is the steady state map. Copyright © 2012 Gas Turbine Society of Japan.
Chiong MS, Rajoo S, Martinez-Botas RF, et al., 2012, Engine turbocharger performance prediction: One-dimensional modeling of a twin entry turbine, ENERGY CONVERSION AND MANAGEMENT, Vol: 57, Pages: 68-78, ISSN: 0196-8904
- Author Web Link
- Cite
- Citations: 69
Copeland CD, Newton PJ, Martinez-Botas R, et al., 2012, The Effect of Unequal Admission on the Performance and Loss Generation in a Double-Entry Turbocharger Turbine, JOURNAL OF TURBOMACHINERY-TRANSACTIONS OF THE ASME, Vol: 134, ISSN: 0889-504X
- Author Web Link
- Cite
- Citations: 17
Lorf C, Martinez-Botas RF, Brandon N, 2012, 26,500km down the Pan-American Highway in an electric vehicle a battery's perspective, SAE Technical Papers, Vol: 1, Pages: 19-26, ISSN: 0148-7191
This paper presents a novel battery degradation model based on empirical data from the Racing Green Endurance project. Using the rainflow-counting algorithm, battery charge and discharge data from an electric vehicle has been studied in order to establish more reliable and more accurate predictions for capacity and power fade of automotive traction batteries than those currently available. It is shown that for the particular lithium-iron phosphate (LiFePO4) batteries, capacity fade is 5.8% after 87 cycles. After 3,000 cycles it is estimated to be 32%. Both capacity and power fade strongly depend on cumulative energy throughput, maximum C-rate as well as temperature. Copyright © 2012 SAE International.
Pesiridis A, Salim WSIW, Martinez-Botas RF, 2012, Turbocharger matching methodology for improved exhaust energy recovery, Pages: 203-218
Current engine simulation codes rely on user-input turbine maps to predict the performance of turbocharged engines. These experimentally obtained maps are limited in range as they are typically obtained through the use of an aerodynamically limited turbine loading device, the compressor. In order to extend the range of the map for simulation, several fitting techniques are utilized in order to obtain the values of efficiency and mass flow over the entire range of pressure ratio for all speeds. This investigation compares predicted turbine maps, obtained from narrow ranges of pressure ratio with more reliable, wider maps obtained experimentally for the same turbines by replacing the compressor with a dynamometer. The outcome of this investigation can be used to improve the fitting of efficiency and mass flow rate curves in engine simulation software. © The author(s) and/or their employer(s), 2012.
Copeland CD, Newton P, Martinez-Botas RF, et al., 2012, A comparison of timescales within a pulsed flow turbocharger turbine, Pages: 389-404
Most modern turbocharger turbines are driven by a highly pulsating flow generated at the exhaust valve of an internal combustion engine. The amplitude and frequency of the exhaust pulses can influence the performance of the turbine when compared to steady state operation. It is useful to seek to simplify the problem of unsteadiness such that greater understanding may result. This paper uses a combination of experimental and computational results to study the various timescales associated with pulsed turbine operation. The effect of pulse amplitude and frequency on the unsteady flow in the volute and rotor is discussed. © The author(s) and/or their employer(s), 2012.
Copeland C, Martinez-Botas R, Turner J, et al., 2012, Boost system selection for a heavily downsized spark ignition prototype engine, Pages: 27-41
The Ultraboost project outlined in this paper seeks to develop a highly pressure-charged, downsized, spark ignition engine that is capable of a 35% reduction in tailpipe CO2 emissions over a naturally aspirated 5.0L V8 while still maintaining performance, emissions and transient response. This project is especially ambitious since, in order to achieve this level of fuel economy improvement, a 60% reduction in engine displacement is targeted with a BMEP of greater than 30bar. What is more, achieving these targets in a gasoline engine with stoichiometric fuelling requires careful design and component selection in order to address the many challenges surrounding gasoline combustion under such high boost pressures. This paper describes a critical examination of the competing requirements of a heavily downsized, gasoline engine with a specific focus on the role of the boosting system in delivering these requirements. From this analysis, the optimal base boosting system configuration is investigated. In addition, a number of boosting technologies, ranging from the novel to the more traditional, are discussed in view of their ability to fulfil a role on the Ultraboost engine. A set of assessment criteria is presented in order to facilitate the selection process. Finally, a 1-D GT-Power model of the Ultraboost engine equipped with the different boosting systems was used to generate an informed rating of all boosting options and permit a reliable comparison with respect to the targets of the project. © The author(s) and/or their employer(s), 2012.
Padzillah MH, Rajoo S, Martinez-Botas RF, 2012, Numerical Assessment of Unsteady Flow Effects on a Nozzled Turbocharger Turbine, ASME Turbo Expo 2012, Publisher: AMER SOC MECHANICAL ENGINEERS, Pages: 745-+
- Author Web Link
- Cite
- Citations: 4
Chiong MS, Rajoo S, Romagnoli A, et al., 2012, UNSTEADY PERFORMANCE PREDICTION OF A SINGLE ENTRY MIXED FLOW TURBINE USING 1-D GAS DYNAMIC CODE EXTENDED WITH MEANLINE MODEL, ASME Turbo Expo 2012, Publisher: AMER SOC MECHANICAL ENGINEERS, Pages: 781-795
- Author Web Link
- Cite
- Citations: 9
Pesiridis A, Lioutas S, Martinez-Botas RF, 2012, Integration of Unsteady Effects in the Turbocharger Design Process, ASME Turbo Expo 2012, Publisher: AMER SOC MECHANICAL ENGINEERS, Pages: 721-733
- Author Web Link
- Cite
- Citations: 1
Mamat AMI, Padzillah MH, Romagnoli A, et al., 2012, A HIGH PERFORMANCE LOW PRESSURE RATIO TURBINE FOR ENGINE ELECTRIC TURBOCOMPOUNDING, ASME Turbo Expo 2011, Publisher: AMER SOC MECHANICAL ENGINEERS, Pages: 771-+
- Author Web Link
- Cite
- Citations: 5
Yang M, Martinez-Botas R, Bamba T, et al., 2012, Investigation of Self-Recycling-Casing-Treatment (SRCT) Influence on Stability of High Pressure Ratio Centrifugal Compressor with a Volute, ASME Turbo Expo 2011, Publisher: AMER SOC MECHANICAL ENGINEERS, Pages: 1857-+
Pesiridis A, Dubois B, Martinez-Botas RF, 2012, A One-Dimensional Investigation of the Effect of an Active Control Turbocharger on Internal Combustion Engine Performance, ASME Turbo Expo 2011, Publisher: AMER SOC MECHANICAL ENGINEERS, Pages: 961-969
Romagnoli A, Copeland C, Martinez-Botas R, et al., 2012, COMPARISON BETWEEN THE STEADY PERFORMANCE OF DOUBLE-ENTRY AND TWIN-ENTRY TURBOCHARGER TURBINES, ASME Turbo Expo 2011, Publisher: AMER SOC MECHANICAL ENGINEERS, Pages: 1995-2007
Romagnoli A, Copeland C, Martinez-Botas RF, et al., 2012, Comparison Between the Steady Performance of Double-Entry and Twin-Entry Turbocharger Turbines, Journal of Turbomachinery
Romagnoli A, Martinez-Botas RF, 2012, Heat transfer analysis in a turbocharger turbine: An experimental and computational evaluation, Applied Thermal Engineering, Vol: 38, Pages: 58-77
Rajoo S, Romagnoli A, Martinez-Botas RF, 2012, Unsteady performance analysis of a twin-entry variable geometry turbocharger turbine, Energy, Vol: 38, Pages: 176-189
Newton P, Copeland C, Martinez-Botas RF, et al., 2012, An Audit of Aerodynamic Loss in a Double Entry Turbine under Full and Partial Admission, International Journal of Heat and Fluid Flow, Vol: 33, Pages: 70-80
Copeland C, Martinez-Botas RF, Seiler M, 2012, Unsteady performance of a twin entry turbocharger turbine with a comparison to steady flow conditions, Jounal of Turbomachinery Trasactions of ASME, Vol: 134, Pages: 021022-1-021022-11
Chiong MS, Rajoo S, Costall AW, et al., 2011, Inlet boundary condition study for unsteady turbine performance prediction using 1-D modeling, Jurnal Mekanikal, Vol: 33, Pages: 89-104
Hey J, Howey DA, Martinez-Botas R, et al., 2011, Transient thermal modelling of an Axial Flux Permanent Magnet (AFPM) machine with model parameter optimisation using a Monte Carlo method, Vehicle Thermal Management Systems VTMS 10, Publisher: IMechE
Howey DA, Martinez-Botas RF, Lytton L, et al., 2011, Comparative measurements of the energy consumption of 51 electric, hybrid and internal combustion engine vehicles, Transportation Research Part D, Vol: 6, Pages: 459-464
Costall AW, McDavid RM, Martinez-Botas RF, et al., 2011, Pulse Performance Modeling of a Twin Entry Turbocharger Turbine Under Full and Unequal Admission, JOURNAL OF TURBOMACHINERY-TRANSACTIONS OF THE ASME, Vol: 133, ISSN: 0889-504X
- Author Web Link
- Cite
- Citations: 34
This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.