waste heat recovery WASTE HEAT RECOVERY LEADS TO HIGHER ECONOMIC EFFICIENCY IN HEAVY-DUTY FLEETS Despite many years of work on optimizing the diesel engine, advanced commercial vehicles only use about 45 percent of the consumed fuel energy for actually driving the vehicle. One of the approaches adopted to enhance overall efficiency involves recovering waste heat, a technology that can lower fuel consumption by 3 to 5 percent. > Fully integrated AVL waste heat recovery system for commercial vehicles. Waste heat recovery (WHR) technology, based on the Rankine cycle, is proving to be a promising method to recover heat. The circulation 3 0 F O C U S process involves overheating and evaporating a working fluid which is then passed into an expansion device, and finally through a condenser where it is re-condensed. The mechanical energy recovered in the expander can be used either mechanically or electrically. WHR TECHNOLOGY CLOSE TO SERIES MATURITY In several research programs, AVL has brought the WHR technology close to series maturity and has gained unequalled expertise in the field. Various system specifications were developed and tested in hardware. In these programs, the technology was shown to reduce fuel consumption in heavy-duty vehicles in real driving operation by around 3-5 percent, depending on the application, achieving a significant improvement in the truck‘s fuel economy. At the AVL International Commercial Powertrain Conference in 2015, AVL presented a WHR truck that was developed in cooperation with IVECO and will now be starting on-road operation for the further optimization of the WHR system. SYSTEM LAYOUT AND OPTIMIZATION AVL has developed a specific methodology to obtain a detailed analysis of the thermodynamic cycle (Organic Rankine Cycle, ORC) and for establishing the necessary component specifications and boundary conditions. The accurate representation of the fuel consumption advantage and the overall system’s behavior in real driving at a very early phase of the development process necessitates the reproduction of all of the relationships and dependencies in the vehicle subsystems in close detail. Accordingly, the individual energy flows present in the truck (of a mechanical, thermal, hydraulic or electric nature) have
FOCUS_Aug_2015_E
To see the actual publication please follow the link above