Imperial College London

ProfessorRicardoMartinez-Botas

Faculty of EngineeringDepartment of Mechanical Engineering

Professor of Turbo-machinery
 
 
 
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Contact

 

+44 (0)20 7594 7241r.botas Website

 
 
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Location

 

611City and Guilds BuildingSouth Kensington Campus

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Summary

 

Publications

Publication Type
Year
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194 results found

Abas MA, Zainal Abidin SF, Rajoo S, Martinez-Botas R, Ismail MIet al., 2017, Evaluation between Engine Stop/Start and Cylinder Deactivation Technologies under Southeast Asia Urban Driving Condition

Copyright © 2017 SAE International. Engine stop/start and cylinder deactivation are increasingly in use to improve fuel consumption of internal combustion engine in passenger cars. The stop/start technology switches off the engine to whenever the vehicle is at a stand-still, typically in a highly-congested area of an urban driving. The inherent issue with the implementation of stop/start technology in Southeast Asia, with tropical climate such as Malaysia, is the constant demand for the air-conditioning system. This inevitably reduces the duration of engine switch-off when the vehicle at stop and consequently nullifying the benefit of the stop/start system. On the other hand, cylinder deactivation technology improves the fuel consumption at certain conditions during low to medium vehicle speeds, when the engine is at part load operation only. This study evaluates the fuel economy benefit between the stop/start and cylinder deactivation technologies for the actual Kuala Lumpur urban driving conditions in Malaysia. Malaysia is chosen as a case study to represent a typical urban environment in Southeast Asia. A 1.6 L PFI 4-cylinder engine is modeled in one-dimensional gas dynamics software to predict the fuel consumption. A transient driving profile obtained from the actual road test over the Kuala Lumpur route is simulated and the fuel consumption is compared with New European Drive Cycle (NEDC). The results provide useful insight and enable manufacturers to assess and consider which of the two technologies offers more impact on the fuel economy and the challenges under urban driving in Southeast Asia conditions.

CONFERENCE PAPER

Andwari AM, Pesiridis A, Rajoo S, Martinez-Botas R, Esfahanian Vet al., 2017, A review of Battery Electric Vehicle technology and readiness levels, RENEWABLE & SUSTAINABLE ENERGY REVIEWS, Vol: 78, Pages: 414-430, ISSN: 1364-0321

JOURNAL ARTICLE

Barrera-Medrano ME, Newton P, Martinez-Botas R, Rajoo S, Tomita I, Ibaraki Set al., 2017, Effect of Exit Pressure Pulsation on the Performance and Stability Limit of a Turbocharger Centrifugal Compressor, JOURNAL OF ENGINEERING FOR GAS TURBINES AND POWER-TRANSACTIONS OF THE ASME, Vol: 139, ISSN: 0742-4795

JOURNAL ARTICLE

Ding Z, Zhuge W, Zhang Y, Chen H, Martinez-Botas R, Yang Met al., 2017, A one-dimensional unsteady performance model for turbocharger turbines, ENERGY, Vol: 132, Pages: 341-355, ISSN: 0360-5442

JOURNAL ARTICLE

Padzillah MH, Yang M, Rajoo S, Martinez-Botas RFet al., 2017, Experimental Work on the Characterization of the Hysteresis Behavior of the Vaned and Vaneless Mixed-Flow Turbocharger Turbine, Journal of Energy Engineering, Vol: 143, ISSN: 0733-9402

© 2017 American Society of Civil Engineers. It has been proven that the turbocharger turbine operates differently under unsteady flow conditions as compared to steady flow. Despite this, the turbine wheel is still designed under the assumption of steady flow conditions. This results in overprediction of the efficiency during actual conditions, which are always pulsating because of the reciprocating nature of an internal combustion engine. The difficulties in characterizing turbine behavior under pulsating flow conditions is attributable to complexities in characterizing the mass flow imbalance and its deviation from steady-state conditions. This paper attempts to describe the mass flow hysteresis properties that occur as a result of the filling and emptying phenomena as the flow frequency is increased from 20 to 60 Hz for vaned and vaneless turbine stators. The phenomena, coupled with difficulties in obtaining instantaneous mass flow rate, resulted in a complex experimental arrangement. Results indicated that the hysteresis properties of each frequency differ substantially, depending on the differences of the propagation velocity between the bulk flow and pressure. The hysteresis loop for vaned turbines also seems to have a larger range than its vaneless counterpart.

JOURNAL ARTICLE

Romagnoli A, Manivannan A, Rajoo S, Chiong MS, Feneley A, Pesiridis A, Martinez-Botas RFet al., 2017, A review of heat transfer in turbochargers, RENEWABLE & SUSTAINABLE ENERGY REVIEWS, Vol: 79, Pages: 1442-1460, ISSN: 1364-0321

JOURNAL ARTICLE

Romagnoli A, Vorraro G, Rajoo S, Copeland C, Martinez-Botas Ret al., 2017, Characterization of a supercharger as boosting & turbo-expansion device in sequential multi-stage systems, ENERGY CONVERSION AND MANAGEMENT, Vol: 136, Pages: 127-141, ISSN: 0196-8904

JOURNAL ARTICLE

Barrera-Medrano ME, Newton P, Martinez-Botas R, Rajoo S, Tomita I, Ibaraki Set al., 2016, EFFECT OF EXIT PRESSURE PULSATION ON THE PERFORMANCE AND STABILITY LIMIT OF A TURBOCHARGER CENTRIFUGAL COMPRESSOR, ASME Turbo Expo: Turbine Technical Conference and Exposition, Publisher: AMER SOC MECHANICAL ENGINEERS

CONFERENCE PAPER

Bin Mamat AMI, Martinez-Botas RF, Rajoo S, Hao L, Romagnoli Aet al., 2016, Design methodology of a low pressure turbine for waste heat recovery via electric turbocompounding, APPLIED THERMAL ENGINEERING, Vol: 107, Pages: 1166-1182, ISSN: 1359-4311

JOURNAL ARTICLE

Chiong MS, Rajoo S, Romagnoli A, Costall AW, Martinez-Botas RFet al., 2016, One-dimensional pulse-flow modeling of a twin-scroll turbine, ENERGY, Vol: 115, Pages: 1291-1304, ISSN: 0360-5442

JOURNAL ARTICLE

Fu H, Cao K, Xu R, Bhouri MA, Martinez-Botas R, Kim S-G, Yeatman EMet al., 2016, Footstep Energy Harvesting Using Heel Strike-Induced Airflow for Human Activity Sensing, 13th IEEE International Conference on Wearable and Implantable Body Sensor Networks (BSN), Publisher: IEEE, Pages: 124-129, ISSN: 2376-8886

CONFERENCE PAPER

Hey J, Malloy AC, Martinez-Botas R, Lamperth Met al., 2016, Online Monitoring of Electromagnetic Losses in an Electric Motor Indirectly Through Temperature Measurement, IEEE TRANSACTIONS ON ENERGY CONVERSION, Vol: 31, Pages: 1347-1355, ISSN: 0885-8969

JOURNAL ARTICLE

Merla Y, Wu B, Yufit V, Brandon NP, Martinez-Botas RF, Offer GJet al., 2016, Novel application of differential thermal voltammetry as an in-depth state-of-health diagnosis method for lithium-ion batteries, JOURNAL OF POWER SOURCES, Vol: 307, Pages: 308-319, ISSN: 0378-7753

JOURNAL ARTICLE

Merla Y, Wu B, Yufit V, Brandon NP, Martinez-Botas RF, Offer GJet al., 2016, Extending battery life: A low-cost practical diagnostic technique for lithium-ion batteries, JOURNAL OF POWER SOURCES, Vol: 331, Pages: 224-231, ISSN: 0378-7753

JOURNAL ARTICLE

Padzillah MH, Rajoo S, Martinez-Botas RF, 2016, PRESSURE DISTRIBUTION ON THE BLADE SURFACE OF AN AUTOMOTIVE MIXED FLOW TURBOCHARGER TURBINE UNDER PULSATING FLOW CONDITIONS, JURNAL TEKNOLOGI, Vol: 78, Pages: 147-153, ISSN: 0127-9696

JOURNAL ARTICLE

Padzillah MH, Rajoo S, Martinez-Botas RF, 2016, COMPARISON OF FLOW FIELD BETWEEN STEADY AND UNSTEADY FLOW OF AN AUTOMOTIVE MIXED FLOW TURBOCHARGER TURBINE, JURNAL TEKNOLOGI, Vol: 78, Pages: 1-7, ISSN: 0127-9696

JOURNAL ARTICLE

Robertson MC, Costall AW, Newton PJ, Martinez-Botas RFet al., 2016, RADIAL TURBOEXPANDER OPTIMIZATION OVER DISCRETIZED HEAVY-DUTY TEST CYCLES FOR MOBILE ORGANIC RANKINE CYCLE APPLICATIONS, ASME Turbo Expo: Turbine Technical Conference and Exposition, Publisher: AMER SOC MECHANICAL ENGINEERS

CONFERENCE PAPER

Yang M, Martinez-Botas R, Zhang Y, Zheng Xet al., 2016, Effect of Self-Recirculation-Casing Treatment on High Pressure Ratio Centrifugal Compressor, JOURNAL OF PROPULSION AND POWER, Vol: 32, Pages: 602-610, ISSN: 0748-4658

JOURNAL ARTICLE

Zhao R, Zhuge W, Zhang Y, Yang M, Martinez-Botas Ret al., 2016, Numerical study of a two-stage turbine characteristic under pulsating flow conditions, JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY, Vol: 30, Pages: 557-565, ISSN: 1738-494X

JOURNAL ARTICLE

von Srbik M-T, Marinescu M, Martinez-Botas RF, Offer GJet al., 2016, A physically meaningful equivalent circuit network model of a lithium-ion battery accounting for local electrochemical and thermal behaviour, variable double layer capacitance and degradation, JOURNAL OF POWER SOURCES, Vol: 325, Pages: 171-184, ISSN: 0378-7753

JOURNAL ARTICLE

Abas M, Martinez-Botas R, 2015, Engine Operational Benefits with Cylinder Deactivation in Malaysian Urban Driving Conditions

Copyright © 2015 SAE International. Cylinder deactivation has been utilized by vehicle manufacturers since the 80's to improve fuel consumption and exhaust emissions. Cylinder deactivation is achieved by cutting off fuel supply and ignition in some of the engine cylinders, while their inlet and outlet valves are fully closed. The vehicle demand during cylinder deactivation is sustained by only the firing cylinders, hence increasing their indicated power. Conventionally, half the number of cylinders are shut at certain driving conditions, which normally at the lower demand regime. An optimal strategy will ensure cylinder deactivation contributes to the fuel saving without compromising the vehicle drivability. Cylinder deactivation has been documented to generally improve fuel consumption between 6 to 25 %, depending on the type-approval test drive cycle. However, type-approval test has been reported to differ from the "real-world" fuel consumption values. Therefore the documented fuel consumption might not be representable for consumers in their actual driving. The Malaysian authorities have been using the NEDC test to measure the emission and fuel consumption for declaration purposes, which may be misleading. This paper presents the measurement and analysis of an engine operating with cylinder deactivation, tested on a dynamometer in accordance to the actual driving conditions rather than the NEDC. This is to understand the actual benefits of cylinder deactivation in the real world. The regular Malaysian urban driving conditions were previously identified and applied in this analysis. To understand the engine operational behaviour, a piezoelectric sensor was instrumented on the engine to acquire the in-cylinder pressure traces. Test results from this study have shown that cylinder deactivation improves fuel consumption and thermodynamic efficiencies for the actual Malaysian driving conditions. The fuel consumption benefit also correlates well with the

CONFERENCE PAPER

Bin Mamat AMI, Martinez-Botas RF, Chiong MC, Rajoo S, Petrovic S, Romagnoli Aet al., 2015, International Conference of Applied Energy 2015, 7th International Conference on Applied Energy (ICAE), Publisher: ELSEVIER SCIENCE BV, Pages: 1555-1559, ISSN: 1876-6102

CONFERENCE PAPER

Bin Mamat AMI, Martinez-Botas RF, Rajoo S, Romagnoli A, Petrovic Set al., 2015, Waste heat recovery using a novel high performance low pressure turbine for electric turbocompounding in downsized gasoline engines: Experimental and computational analysis, ENERGY, Vol: 90, Pages: 218-234, ISSN: 0360-5442

JOURNAL ARTICLE

Cao K, Yang M, Martinez-Botas RF, 2015, A NUMERICAL INVESTIGATION ON A NEW PULSE-OPTIMIZED FLOW CONTROL METHOD FOR TURBOCHARGER TURBINE PERFORMANCE IMPROVEMENT UNDER PULSATING CONDITIONS, ASME Turbo Expo: Turbine Technical Conference and Exposition, Publisher: AMER SOC MECHANICAL ENGINEERS

CONFERENCE PAPER

Chiong MS, Rajoo S, Romagnoli A, Costal AW, Martinez-Botas RFet al., 2015, ASSESSMENT OF PARTIAL-ADMISSION CHARACTERISTICS IN TWIN-ENTRY TURBINE PULSE PERFORMANCE MODELLING, ASME Turbo Expo: Turbine Technical Conference and Exposition, Publisher: AMER SOC MECHANICAL ENGINEERS

CONFERENCE PAPER

Chiong MS, Rajoo S, Romagnoli A, Costall AW, Martinez-Botas RFet al., 2015, Non-adiabatic pressure loss boundary condition for modelling turbocharger turbine pulsating flow, ENERGY CONVERSION AND MANAGEMENT, Vol: 93, Pages: 267-281, ISSN: 0196-8904

JOURNAL ARTICLE

Cicciotti M, Xenos DP, Bouaswaig AEF, Thornhill NF, Martinez-Botas RFet al., 2015, Physical modelling of industrial multistage centrifugal compressors for monitoring and simulation, PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART C-JOURNAL OF MECHANICAL ENGINEERING SCIENCE, Vol: 229, Pages: 3433-3448, ISSN: 0954-4062

JOURNAL ARTICLE

Costall AW, Hernandez AG, Newton PJ, Martinez-Botas RFet al., 2015, Design methodology for radial turbo expanders in mobile organic Rankine cycle applications, APPLIED ENERGY, Vol: 157, Pages: 729-743, ISSN: 0306-2619

JOURNAL ARTICLE

Gambhir A, Tse LKC, Tong D, Martinez-Botas Ret al., 2015, Reducing China's road transport sector CO2 emissions to 2050: Technologies, costs and decomposition analysis, APPLIED ENERGY, Vol: 157, Pages: 905-917, ISSN: 0306-2619

JOURNAL ARTICLE

Hey J, Malloy AC, Martinez-Botas R, Lamperth Met al., 2015, Conjugate heat transfer analysis of an energy conversion device with an updated numerical model obtained through inverse identification, ENERGY CONVERSION AND MANAGEMENT, Vol: 94, Pages: 198-209, ISSN: 0196-8904

JOURNAL ARTICLE

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