Extending NREL's FASTSim to model catalyst transient warmup behavior
2022-01-0578
03/29/2022
- Event
- Content
- A custom version of NREL's FASTSim was extended to include transient thermal models for engine and catalysts with the goal of understanding catalyst warmup dynamics during cold start for light duty vehicles representing a range of vehicle sizes, makes, and models, including a small sedan and multiple SUV or truck body types. The model was calibrated and separately validated for various each vehicle using dynamometer test data conducted over various regulatory drive cycles and a sweep of ambient and initial conditions ranging from -20°C to 40°C. The NSGA-II multi-objective-optimization algorithm in Python's PyMOO package was used to select calibration parameters to identify the Pareto minimal hyper-surface of time-weighted engine temperature, catalyst temperature, and fueling errors for each test data set. By scaling component parameters with respect to engine peak power, the model was then exercised over a nationally representative range of initial temperatures, ambient temperatures, and vehicle speed profiles to determine the warmup improvement resulting from various novel catalyst control strategies. FASTSim enhancements were open sourced as part of the publicly available FASTSim code base.
- Citation
- Baker, C., "Extending NREL's FASTSim to model catalyst transient warmup behavior," SAE Technical Paper 2022-01-0578, 2022, .