1. Date of download: 7/9/2016 Copyright © ASME. All rights reserved. From: Effect of the Ratio Spread of CVU in Automotive Kinetic Energy Recovery Systems J. Mech. Des. 2013;135(6):061001-061001-9. doi:10.1115/1.4024121 Schematic of the driveline of the mechanical hybrid vehicle. Sections of the driveline are tagged with numbers. FR is the Fixed Ratio final drive of the vehicle driveline, FM is the Final Multiplier. The variator can be of two types: single-unit mechanical CVT (toroidal traction drive for instance) or PS-CVT architecture, where PG is the planetary gear. The KERS is plugged in the vehicle propshaft through a friction clutch. A second clutch (not shown in the figure) can disconnect the FM from the variable drive when the flywheel is in idle rotation. Figure Legend:

2. Date of download: 7/9/2016 Copyright © ASME. All rights reserved. From: Effect of the Ratio Spread of CVU in Automotive Kinetic Energy Recovery Systems J. Mech. Des. 2013;135(6):061001-061001-9. doi:10.1115/1.4024121 Schematic of the power flows (arrows) in the shunted CVT architecture. PG is the planetary gear drive, FR is the fixed-ratio drive. In the forward mode or direct operation the power input is the shaft 4 and the output is the shaft 3. In the reverse operation, the power input is the shaft 3 and the output is the shaft 4. Figure Legend:

3. Date of download: 7/9/2016 Copyright © ASME. All rights reserved. From: Effect of the Ratio Spread of CVU in Automotive Kinetic Energy Recovery Systems J. Mech. Des. 2013;135(6):061001-061001-9. doi:10.1115/1.4024121 The efficiency of PS-CVT as a function of the τPS with internal power recirculation of (a) type I and (b) type II in direct (thick dashed line) and reverse (thick continuous line) operation. The efficiency of the CVT (thin line) is constant ηCVT=0.92, the lower and upper bounds of the CVT ratio are τCVTmin=0.4,τCVTmax=2.5, the lower and upper bounds of the PS-CVT ratio (vertical thin dashed lines) τPSmin=0.2,τPSmax=2.5 corresponding to rrPS=12.5, and ηFR=0.97. Figure Legend:

4. Date of download: 7/9/2016 Copyright © ASME. All rights reserved. From: Effect of the Ratio Spread of CVU in Automotive Kinetic Energy Recovery Systems J. Mech. Des. 2013;135(6):061001-061001-9. doi:10.1115/1.4024121 The federal test procedure driving schedule. The first part is the urban FTP-75, followed by the extra-urban HFET driving schedule. Figure Legend:

5. Date of download: 7/9/2016 Copyright © ASME. All rights reserved. From: Effect of the Ratio Spread of CVU in Automotive Kinetic Energy Recovery Systems J. Mech. Des. 2013;135(6):061001-061001-9. doi:10.1115/1.4024121 The average power loss in the clutch as a function of the minimum value of the τPS in FTP-75 driving schedule. The variator is ideal (unitary efficiency) in this simulation. The horizontal dotted line emphasizes the value given by the system with direct drive CVT (marked with a dot). Figure Legend:

6. Date of download: 7/9/2016 Copyright © ASME. All rights reserved. From: Effect of the Ratio Spread of CVU in Automotive Kinetic Energy Recovery Systems J. Mech. Des. 2013;135(6):061001-061001-9. doi:10.1115/1.4024121 KERS boost as a function of the τPSmin in FTP-75 driving shedule. The variator is ideal (unitary efficiency) in this simulation. The horizontal dotted line emphasizes the value given by the system with direct drive CVT (marked with a dot). Figure Legend:

7. Date of download: 7/9/2016 Copyright © ASME. All rights reserved. From: Effect of the Ratio Spread of CVU in Automotive Kinetic Energy Recovery Systems J. Mech. Des. 2013;135(6):061001-061001-9. doi:10.1115/1.4024121 (a) The KERS boost and (b) the round-trip efficiency in the FTP-75 driving schedule as a function of the lower bound of the PS-CVT ratio τPSmin. The results are shown for internal power flows of types I, II, and III and the direct drive CVT. The horizontal dotted line emphasizes the value given by the system with direct drive CVT (marked with a dot). Figure Legend:

8. Date of download: 7/9/2016 Copyright © ASME. All rights reserved. From: Effect of the Ratio Spread of CVU in Automotive Kinetic Energy Recovery Systems J. Mech. Des. 2013;135(6):061001-061001-9. doi:10.1115/1.4024121 (a) The average power loss in the variator and (b) in the clutch in the FTP-75 driving schedule as a function of the lower bound of the PS-CVT ratio τPSmin. Internal power flows of types I, II, and III and direct drive CVT are considered. The horizontal dotted line emphasizes the value given by the system with direct drive CVT (marked with a dot). Figure Legend:

9. Date of download: 7/9/2016 Copyright © ASME. All rights reserved. From: Effect of the Ratio Spread of CVU in Automotive Kinetic Energy Recovery Systems J. Mech. Des. 2013;135(6):061001-061001-9. doi:10.1115/1.4024121 The KERS boost as a function of the lower bound of the variable drive ratio τPSmin at different values of the upper bound of the flywheel angular velocity. In the comparison the maximum energy which can be stored in the flywheel is kept constant and equal to 178 kJ. Simulations have been performed with PS-CVT with power flow of type II or III and with direct drive CVT. Figure Legend:

10. Date of download: 7/9/2016 Copyright © ASME. All rights reserved. From: Effect of the Ratio Spread of CVU in Automotive Kinetic Energy Recovery Systems J. Mech. Des. 2013;135(6):061001-061001-9. doi:10.1115/1.4024121 (a) The KERS boost and (b) the round-trip efficiency in the FTP-75 driving schedule as a function of the lower bound of the PS-CVT ratio τPSmin. The results are shown considering the internal power circulations of types I, II, and III and the direct drive CVT (marked with a dot). In these simulations, the CVT efficiency has been supposed constant and equal to 0.97. Figure Legend: