The light-duty (LD) automotive landscape has changed significantly in the last few years. The rapid adoption of electrification and fully electric powertrains has reduced pure internal combustion engines (ICE) budgets. Heavy-duty (HD) companies are also starting to ramp up their efforts in electrification, posing further challenges for future ICE work. There has, however, been an increase in studies related to hybrid powertrains. This simulation-based internal research project investigated ways in which electrification could be used to overcome historic challenges with the internal combustion engine. The aim was to find new strategies to reduce the vehicle’s fuel consumption and lifetime carbon footprint.
The PDIR was split into two main phases. In the first phase, a modeling toolset was created that enabled engine and vehicle-level simulation of hybridized powertrains. Three different vehicle models were created: light-duty, medium-duty and heavy-duty. These models were validated against published and in-house test data to ensure accuracy. In addition to simulating tailpipe emissions, CO2 emissions created over the life of the vehicle were also assessed. This life-cycle CO2 analysis was performed using the Greenhouse gas, Regulation Emissions and Energy use in Transportation model (GREET).
After the toolset was successfully created and validated, work began looking at various concepts which could be enabled by electrification. The light-duty team focused on six technology areas related to ICE efficiency, while the heavy-duty team focused on four areas enabled by smaller hybrid systems.
A model was developed which enables vehicle-level simulation of various ICE and hybrid configurations.
These models form a core part of both the current CHEDE 8 program and future HEDGE V program.
Both the LD and HD teams successfully used these models to demonstrate improvements in engine efficiency and life-cycle carbon footprint.
The LD team demonstrated up to 7% thermal efficiency improvement through changes to the ICE for a series-hybrid application.
The HD team was able to demonstrate 14% fuel economy benefit by using electrification to enable downsizing.
Data from the IR has been used in several proposals, mainly for life-cycle analysis studies. Data has also been shared with CHEDE and HEDGE members to demonstrate our capability in this area. There is a large effort in CHEDE now to look at the role of electrification on HD engines.
To date, five papers and four invention disclosures have been created using this IR data.