“Divided Flow VNT for HD Truck Engines”
Many Commercial Vehicle engines use divided turbine housings to separate the flows of cylinders 1-2-3 and 4-5-6. The separation of flows all the way to the turbine wheel eliminates negative interactions between the exhaust gas pulses of different cylinders. Despite this, some of the best L6 engines still use VNT turbochargers with Open Volute turbines, largely because some applications have challenging torque curves and need to support engine braking.
Until now, the industry has had to choose between divided flow WG or open volute VNT. Garrett Motion has broken this age-old paradigm by innovating a Sector Divided VNT (SD-VNT). The new concept separates the flows all the way to the VNT cartridge and preserves the pulse energy for the turbine to utilize to its full advantage.
This development has been carried out in conjunction with FPT on their new XC13 engine. The powertrain implements a down-speeding concept to reduce the CO2 emissions of Long-Haul Trucks. The engine is designed to operate at 150…200 rpm lower speed than its predecessor.
1D analysis demonstrates how the Sector Divided GT45VGen 4 reduces the pumping work of the engine and captures the high energy content of the pulse for the turbocharger. The results show that the engine efficiency improves while the residuals are minimized. Back-to-back engine tests confirm the BSFC benefits that are achieved already by dividing the flow without needing to modify the aerodynamics.
Presentation Date: Tuesday, September 26th, 11:00 AM
Authors: L. Jaeger, P. Pribyl, F. Eckl, P. Foucek from Garrett Motion and F. Paulicelli, S. Kumar from FPT Industrial, IVECO GROUP
“Project PHOENICE and the role of an E-Turbo in a high-efficiency PHEV“
Presentation Date: Tuesday, September 26th, 02:30 PM
In the current climate for the decarbonization of on-road transport and the search for innovative and environmentally conscious powertrains, the PHOENICE project (PHev towards zerO EmissioNs & ultimate ICE efficiency) is conceived. The project has a target of developing a C-SUV class demo vehicle equipped with a highly efficient hybrid powertrain and achieving ultra-low tail pipe emissions. In this framework, Garrett is involved by developing and providing an E-Turbo suited to perform in synergy with the project’s technological bricks, becoming an enabler for the project’s ambitious targets.
To target the high powertrain efficiency, the project developed a dual dilution combustion (DDC) engine that uses EGR and lean combustion. To enable the steady state engine operation in highly diluted conditions, a VNTTM turbine was matched and paired with a state-of-the-art compressor. Additionally, the E-Turbo helps in engine transients, not sacrificing the drivability characteristics of the overall vehicle. The project also takes advantage of the E-Turbo’s features so that it can be working closely together with the aftertreatment system to allow faster catalyst light-off and therefore reducing the real driving emissions.
In this paper, the challenges of the matching activities and design choices of the E-Turbo will be presented and the strong synergies with the vehicle’s system will be discussed in depth. Additionally, the project’s engine steady-state results will be presented.
Presentation Date: Tuesday, September 26th, 2:00 PM
Authors: J. S. Castellanos, N. Bontemps from Garrett Motion; M. Andre from IFPEN; L. Rolando from Politechnico di Torino; V. Ravula from FEV
Publisher: Dresden Technical University
Publication date: 26 of September 2023, at the 27th Supercharging Conference in Dresden, Germany