On the Energy Efficiency of Dual Clutch Transmissions and Automated Manual Transmissions
The main benefits of dual clutch transmissions (DCTs) are: (i) a higher energy efficiency than automatic transmission systems with torque converters; and (ii) the capability to fill the torque gap during gear shifts to allow seamless longitudinal acceleration profiles. Therefore, DCTs are viable alt...
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| Format: | Article |
| Language: | English |
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MDPI AG
2017-10-01
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| Series: | Energies |
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| Online Access: | https://www.mdpi.com/1996-1073/10/10/1562 |
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| author | Fabio Vacca Stefano De Pinto Ahu Ece Hartavi Karci Patrick Gruber Fabio Viotto Carlo Cavallino Jacopo Rossi Aldo Sorniotti |
| author_facet | Fabio Vacca Stefano De Pinto Ahu Ece Hartavi Karci Patrick Gruber Fabio Viotto Carlo Cavallino Jacopo Rossi Aldo Sorniotti |
| author_sort | Fabio Vacca |
| collection | DOAJ |
| description | The main benefits of dual clutch transmissions (DCTs) are: (i) a higher energy efficiency than automatic transmission systems with torque converters; and (ii) the capability to fill the torque gap during gear shifts to allow seamless longitudinal acceleration profiles. Therefore, DCTs are viable alternatives to automated manual transmissions (AMTs). For vehicles equipped with engines that can generate considerable torque, large clutch-slip energy losses occur during power-on gear shifts and, as a result, DCTs need wet clutches for effective heat dissipation. This requirement substantially reduces DCT efficiency because of the churning and ancillary power dissipations associated with the wet clutch pack. To the knowledge of the authors, this study is the first to analyse the detailed power loss contributions of a DCT with wet clutches, and their relative significance along a set of driving cycles. Based on these results, a novel hybridised AMT (HAMT) with a single dry clutch and an electric motor is proposed for the same vehicle. The HAMT architecture combines the high mechanical efficiency typical of AMTs with a single dry clutch, with the torque-fill capability and operational flexibility allowed by the electric motor. The measured efficiency maps of a case study DCT and HAMT are compared. This is then complemented by the analysis of the respective fuel consumption along the driving cycles, which is simulated with an experimentally validated vehicle model. In its internal combustion engine mode, the HAMT reduces fuel consumption by >9% with respect to the DCT. |
| first_indexed | 2024-04-13T00:47:21Z |
| format | Article |
| id | doaj.art-1d8677695e784c248b71fd1d73aee27f |
| institution | Directory Open Access Journal |
| issn | 1996-1073 |
| language | English |
| last_indexed | 2024-04-13T00:47:21Z |
| publishDate | 2017-10-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Energies |
| spelling | doaj.art-1d8677695e784c248b71fd1d73aee27f2022-12-22T03:09:57ZengMDPI AGEnergies1996-10732017-10-011010156210.3390/en10101562en10101562On the Energy Efficiency of Dual Clutch Transmissions and Automated Manual TransmissionsFabio Vacca0Stefano De Pinto1Ahu Ece Hartavi Karci2Patrick Gruber3Fabio Viotto4Carlo Cavallino5Jacopo Rossi6Aldo Sorniotti7Department of Mechanical Engineering Sciences, University of Surrey, Guildford GU2 7XH, UKDepartment of Mechanical Engineering Sciences, University of Surrey, Guildford GU2 7XH, UKDepartment of Mechanical Engineering Sciences, University of Surrey, Guildford GU2 7XH, UKDepartment of Mechanical Engineering Sciences, University of Surrey, Guildford GU2 7XH, UKOerlikon Graziano S.p.A., 10098 Rivoli, ItalyOerlikon Graziano S.p.A., 10098 Rivoli, ItalyOerlikon Graziano S.p.A., 10098 Rivoli, ItalyDepartment of Mechanical Engineering Sciences, University of Surrey, Guildford GU2 7XH, UKThe main benefits of dual clutch transmissions (DCTs) are: (i) a higher energy efficiency than automatic transmission systems with torque converters; and (ii) the capability to fill the torque gap during gear shifts to allow seamless longitudinal acceleration profiles. Therefore, DCTs are viable alternatives to automated manual transmissions (AMTs). For vehicles equipped with engines that can generate considerable torque, large clutch-slip energy losses occur during power-on gear shifts and, as a result, DCTs need wet clutches for effective heat dissipation. This requirement substantially reduces DCT efficiency because of the churning and ancillary power dissipations associated with the wet clutch pack. To the knowledge of the authors, this study is the first to analyse the detailed power loss contributions of a DCT with wet clutches, and their relative significance along a set of driving cycles. Based on these results, a novel hybridised AMT (HAMT) with a single dry clutch and an electric motor is proposed for the same vehicle. The HAMT architecture combines the high mechanical efficiency typical of AMTs with a single dry clutch, with the torque-fill capability and operational flexibility allowed by the electric motor. The measured efficiency maps of a case study DCT and HAMT are compared. This is then complemented by the analysis of the respective fuel consumption along the driving cycles, which is simulated with an experimentally validated vehicle model. In its internal combustion engine mode, the HAMT reduces fuel consumption by >9% with respect to the DCT.https://www.mdpi.com/1996-1073/10/10/1562dual clutch transmissionshybridised automated manual transmissionspower loss contributionsexperimentsdriving cycle simulations |
| spellingShingle | Fabio Vacca Stefano De Pinto Ahu Ece Hartavi Karci Patrick Gruber Fabio Viotto Carlo Cavallino Jacopo Rossi Aldo Sorniotti On the Energy Efficiency of Dual Clutch Transmissions and Automated Manual Transmissions Energies dual clutch transmissions hybridised automated manual transmissions power loss contributions experiments driving cycle simulations |
| title | On the Energy Efficiency of Dual Clutch Transmissions and Automated Manual Transmissions |
| title_full | On the Energy Efficiency of Dual Clutch Transmissions and Automated Manual Transmissions |
| title_fullStr | On the Energy Efficiency of Dual Clutch Transmissions and Automated Manual Transmissions |
| title_full_unstemmed | On the Energy Efficiency of Dual Clutch Transmissions and Automated Manual Transmissions |
| title_short | On the Energy Efficiency of Dual Clutch Transmissions and Automated Manual Transmissions |
| title_sort | on the energy efficiency of dual clutch transmissions and automated manual transmissions |
| topic | dual clutch transmissions hybridised automated manual transmissions power loss contributions experiments driving cycle simulations |
| url | https://www.mdpi.com/1996-1073/10/10/1562 |
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