Primary and Secondary Emissions Reduction Using Cylinder Deactivation Strategies for Gasoline Direct Injection...

Area of Science:

• Automotive Engineering
• Environmental Science
• Catalysis

Background:

• Electrified powertrains in hybrid electric vehicles (HEVs) are driven by stricter CO2 and air quality regulations.
• HEV operation involves frequent cold/warm starts, challenging catalytic converter efficiency and increasing emissions.
• Understanding and mitigating primary and secondary emissions under these conditions is crucial.

Purpose of the Study:

• To investigate energy-efficient technologies for enhancing catalytic reduction of emissions in HEVs.
• To evaluate a novel engine cylinder deactivation strategy for faster catalyst light-off.
• To analyze the impact on both regulated and unregulated secondary emissions (NH3 and N2O).

Main Methods:

• Experimental study of engine cylinder deactivation at various catalyst temperatures.
• Measurement of catalyst temperature increase and tailpipe emissions.
• Quantification of regulated (CO, NO, HC) and unregulated (NH3, N2O) emissions.

Main Results:

• The cylinder deactivation strategy significantly increased Three-Way Catalyst (TWC) temperature by up to 300°C.
• Mass-based emissions of CO, NO, HC, N2O, and NH3 were substantially reduced.
• Faster catalyst light-off was achieved, leading to lower overall emissions.

Conclusions:

• Engine cylinder deactivation is an effective strategy for rapid catalyst heating in HEVs.
• This method reduces both primary and secondary emissions, addressing key environmental concerns.
• Findings inform the optimization of energy-efficient catalyst heating strategies for future HEVs.