Study on exergy recovery in hybrid vehicles via wastegate losses

Abstract

Vehicle hybridization is considered a promising alternative for pollutant emission mitigation. This type of vehicle

combines the use of an internal combustion engine and electrical power. One of the most common layout is the

series-parallel hybrid vehicle, which consists of the use of one combustion engine as the main source of power in

parallel to electrical sources. Besides propelling the vehicle, the combustion engine has the task of supplying energy

to the electrical system. In parallel to hybridization, other technologies, such as the downsizing of an engine via

turbocharging, have been adopted to increase thermal efficiency of internal combustion engines. The purpose of this

work is to analyse the viability of combining the aforementioned technologies. To improve energy utilisation, part of

the energy of the exhaust system is recovered from a free turbine, being directed to the vehicle's battery. To evaluate

the viability of the proposal, experimental data was obtained from a turbocharged spark-ignition engine. Efficiency

indexes were calculated based on exergetic analyses for the turbo-compressor set and the entire engine system.

Thereafter, a virtual free turbine was virtually added, assuming that it operates exactly as the main turbine and the

efficiency indexes were re-calculated as also absolute values of the recovered energy. The comparison of results

indicates the viability of implementing this proposal.

Keywords

• Hybrid vehicles,Gasohol,Exergetic Efficiency,Downsizing,Spark-ignition Engines

Supporting Institution

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Project Number

2013/50238-3, 2018/18859-1

Thanks

The authors would like to express their gratitude to prof. Clayton Barcelos Zabeu and the staff of Mauá Institute of Technology for the execution of the experimental tests and to Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) for the financial support through process No. 2013/50238-3 and 2018/18859-1.

References

1. Noam Lior, Professor of Mechanical Engineering and Applied Mechanics, University of Pennsylvania (US); Guest Professor, Chinese Academy of Sciences.Email: [e-mail]
2. Jamie Turner, Professor, Department of Mechanical Engineering Powertrain and Vehicle Research Centre (PVRC), University of Bath (UK).Email: [e-mail]
3. André Valente Bueno, Associated Professor, Universidade Federal do Ceará (Brazil).Email: [e-mail]