Investigation of Technologies to Improve Fuel Efficiency in Turbo GDI Engine: CDA, Miller-Cycle with Valve Event, Water Injection, LP EGR and High Compression Ratio

Authors

M. S. Choi PhD, Y. H. Kwak, Hyundai Motor Co R&D Center, Namyang, South Korea;
D. Roth, D. Jakiela, J. Song PhD, BorgWarner Corporate Advanced Engineering, Auburn Hills, USA

Year

2019

Print Info

Fortschritt-Berichte VDI, Reihe 12, Nr. 811

Summary

As world-wide CO₂ legislation tightens, the next generation of turbocharged gasoline engines must meet stricter emissions targets combined with increased fuel efficiency standards. Recent studies have shown that the following technologies offer significant improvements to the efficiency of turbocharged GDI engines: Miller Cycle via late intake valve closing (LIVC), low pressure loop cooled EGR (LPL EGR), port water injection (PWI), and cylinder deactivation (CDA). While these efficiency-improving technologies are individually well-understood, in this study we directly compare these technologies to each other on the same engine at a range of operating conditions and over a range of compression ratios (CR). The technologies tested are applied to a boosted and direct injected (DI) gasoline engine and evaluated both individually and combined. The results show for the test engine, given all of the technologies available, what the best combinations are for all tested speeds and loads, at each compression ratio studied. To determine the maximum improvement limits with the combination of these technologies, the modes of vehicle operation such as NEDC, WLTP, FTP, RDE were simulated with data of the entire engine operating area with AVL Cruise.