Coupling of a KERS power train and a downsized 1.2TDI diesel or a 1.6TDI-JI H2 engine for improved fuel economies in a compact car
- Authors: Boretti, Alberto
- Date: 2010
- Type: Text , Conference paper
- Relation: Paper presented at SAE 2010 Powertrains Fuels & Lubricants Meeting, San Diego, USA : 25th-27th October 2010
- Full Text:
- Description: Recovery of braking energy during driving cycles is the most effective option to improve fuel economy and reduce green house gas (GHG) emissions. Hybrid electric vehicles suffer the disadvantages of the four efficiency reducing transformations in each regenerative braking cycle. Flywheel kinetic energy recovery systems (KERS) may boost this efficiency up to almost double values of about 70% avoiding all four of the efficiency reducing transformations from one form of energy to another and keeping the vehicle's energy in the same form as when the vehicle starts braking when the vehicle is back up to speed. With reference to the baseline configuration with a 1.6 liters engine and no recovery of kinetic energy, introduction of KERS reduces the fuel usage to 3.16 liters per 100 km, corresponding to 82.4 g of CO2 per km. The 1.6 liters Turbo Direct Injection (TDI) Diesel engine without KERS uses 1.37 MJ per km of fuel energy, reducing with KERS to 1.13 MJ per km. Downsizing the engine to 1.2 liters as permitted by the torque assistance by KERS, the fuel consumption is further reduced to 3.04 liters per 100 km, corresponding to 79.2 g of CO2 per km and 1.09 MJ per km of fuel energy. These CO2 and fuel usage values are 11% and 13% better than those of today’s highest fuel economy hybrid electric vehicle. The car equipped with a 1.6 liter Turbo Direct Injection Jet Ignition (TDI-JI) H2ICE engine finally consumes 8.3 g per km of fuel, corresponding to only 0.99 MJ per km of fuel energy.
Coupling of a KERS powertrain and a 4 Litre gasoline engine for improved fuel economy in a full size car
- Authors: Boretti, Alberto
- Date: 2010
- Type: Text , Conference paper
- Relation: Paper presented at SAE 2010 Powertrains Fuels & Lubricants Meeting, San Diego, USA : 25th-27th October 2010
- Full Text:
- Description: Improvements of vehicle fuel economy are being considered using a mechanically driven flywheel to reduce the amount of mechanical energy produced by the thermal engine recovering the vehicle kinetic energy during braking. A mechanical system having an overall efficiency over a full regenerative cycle of about 70%, about twice the efficiency of battery-based hybrids, is coupled to a naturally aspirated gasoline engine powering a full size sedan. Results of chassis dynamometer experiments and engine and vehicle simulations are used to evaluate the fuel benefits introducing a kinetic energy recovery system and downsizing of the engine. Preliminary results running the new European driving cycle (NEDC) show KERS may reduce fuel consumption by 25% without downsizing, and 33% with downsizing of the 4 litre engine to 3.3 litres.
Improvements of truck fuel economy using mechanical regenerative braking
- Authors: Boretti, Alberto
- Date: 2010
- Type: Text , Conference paper
- Relation: Paper presented at SAE 2010 Commercial Vehicle Engineering Congress, Illinois, USA : 5th-6th October 2010
- Full Text:
- Description: Improvements of truck fuel economy are being considered using a flywheel energy storage system concept. This system reduces the amount of mechanical energy needed by the thermal engine by recovering the vehicle kinetic energy during braking and then assisting torque requirements. The mechanical system has an overall efficiency over a full regenerative cycle of about 70%, about twice the efficiency of battery-based hybrids rated at about 36%. The technology may improve the vehicle fuel economy and hence reduced CO2 emissions by more than 30% over driving cycles characterized by: frequent engine start/stop, vehicle acceleration, brief cruising, deceleration and stop. The paper uses engine and vehicle simulations to compute: first the fuel benefits of the technology applied to passenger cars, then the extension of the technology to deal with heavy duty vehicles.
Improvements of vehicle fuel economy using mechanical regenerative braking
- Authors: Boretti, Alberto
- Date: 2010
- Type: Text , Conference paper
- Relation: Paper presented at SAE 2010 Annual Brake Colloquium And Engineering Display, Phoenix, USA : 10th-13th October 2010
- Full Text:
- Description: Improvements of fuel economy of passenger cars and light and heavy duty trucks are being considered using a flywheel energy storage system concept to reduce the amount of mechanical energy produced by the thermal engine recovering the vehicle kinetic energy during braking and then assisting torque requirements. The mechanical system has an overall efficiency over a full regenerative cycle of about 70%, about twice the efficiency of battery-based hybrids rated at about 36%. The technology may improve the vehicle fuel economy and hence reduced CO2 emissions by more than 30% over driving cycles characterized by frequent engine start/stop, and vehicle acceleration, brief cruising, deceleration and stop.
Modelling of engine and vehicle for a compact car with a flywheel based kinetic energy recovery systems and a high efficiency small diesel engine
- Authors: Boretti, Alberto
- Date: 2010
- Type: Text , Conference paper
- Relation: Paper presented at SAE 2010 Powertrains Fuels & Lubricants Meeting, San Diego, USA : 25th-27th October 2010
- Full Text:
- Description: Recovery of kinetic energy during driving cycles is the most effective option to improve fuel economy and reduce green house gas (GHG) emissions. Flywheel kinetic energy recovery systems (KERS) may boost this efficiency up to values of about 70%. An engine and vehicle model is developed to simulate the fuel economy of a compact car equipped with a TDI Diesel engine and a KERS. Introduction of KERS reduces the fuel used by the 1.6L TDI engine to 3.16 liters per 100 km, corresponding to 82.4 g of CO2 per km. Downsizing the engine to 1.2 liters as permitted by the torque assistance by KERS, further reduces the fuel consumption to 3.04 liters per 100 km, corresponding to 79.2 g of CO2 per km. These CO2 values are 11% better than those of today’s most fuel efficient hybrid electric vehicle.
Use of variable valve actuation to control the load in a direct injection, turbocharged, spark-ignition engine
- Authors: Boretti, Alberto
- Date: 2010
- Type: Text , Conference paper
- Relation: Paper presented at SAE 2010 Powertrains Fuels & Lubricants Meeting, San Diego, USA : 25th-27th October 2010
- Full Text:
- Description: Downsizing and Turbo Charging (TC) and Direct Injection (DI) may be combined with Variable Valve Actuation (VVA) to better deal with the challenges of fuel economy enhancement. VVA may control the load without throttle; control the valve directly and quickly; optimize combustion, produce large volumetric efficiency. Benefits lower fuel consumption, lower emissions and better performance and fun to drive. The paper presents an engine model of a 1.6 litre TDI VVA engine specifically designed to run pure ethanol, with computed engine maps for brake specific fuel consumption and efficiency. The paper also presents driving cycle results obtained with a vehicle model for a passenger car powered by this engine and a traditional naturally aspirated gasoline engine. Preliminary results of the VVA system coupled with downsizing, turbo charging and Direct Injection permits significant driving cycle fuel economies.
The effectiveness of an ecodrive course for heavy vehicle drivers
- Authors: Symmons, Mark , Rose, Geoffrey , Van Doorn, George
- Date: 2008
- Type: Text , Conference paper
- Relation: Proceedings of the Australasian Road Safety Research, Policing and Education Conference 2008 p. 1-8
- Full Text:
- Reviewed:
- Description: Amongst other changes, ecodriving requires drivers to drive more smoothly – to “flow” the vehicle. In order to save fuel and reduce emissions drivers must operate at lower engine revolutions, change up gears as soon as possible, and anticipate traffic conditions and drive defensively. A field trial was conducted using a 30 km metropolitan circuit and B-double heavy vehicles. Compared to their pre-course measures, the trained group reduced their fuel consumption by an average of 27%, the number of gear changes by 29%, and the number of brake applications by 41%. Importantly, these gains were not offset by increases in the time taken to complete the circuit – indeed average speed increased slightly. Further, the benefits did not lose any strength 12 weeks after the training, at which point the pilot trial concluded – in fact for some variables the results continued to improve over time. The number of drivers participating in the trial was relatively small and some questions remain unanswered, including actual road safety implications, building a strong case for a larger trial.