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Approximately one-third of the fuel energy consumed by an internal combustion engine flows out the tailpipe as waste heat. Thermoelectric devices are being considered as a means of utilizing some of this waste heat to generate electric power on vehicles. A 1.1-liter volume flat plate heat exchanger was fabricated to study the heat transfer characteristics of a conceptual design for thermoelectric waste heat recovery from diesel exhaust, and used to validate a heat exchanger model. The heat exchanger consisted of an exhaust channel and two coolant channels all having rectangular cross-sections. The experimentally measured heat transfer rates were compared with a finite element heat transfer model to be used both for heat exchanger development and modeling thermoelectric device performance. In both the model and the experiment, alumina paper was used as a surrogate for the thermoelectric materials.

Some CO2-reducing technologies have real-world benefits not captured by regulatory testing methods. This paper documents a two-layer heating, ventilation, and air-conditioning (HVAC) system that facilitates faster engine warmup through strategic increased air recirculation. The performance of this technology was assessed on a 2020 Hyundai Sonata. Empirical performance of the technology was obtained through dynamometer tests at Argonne National Laboratory. Performance of the vehicle across multiple cycles and cell ambient temperatures with the two-layer technology active and inactive indicated fuel consumption reduction in nearly all cases. A thermally sensitive powertrain model, the National Renewable Energy Laboratory’s FASTSim Hot, was calibrated and validated against vehicle testing data. The developed model included the engine, cabin, and HVAC system controls.

Heavy-duty commercial vehicles consume a significant amount of energy due to their large size and mass, directly leading to vehicle operators prioritizing energy efficiency to reduce operational costs and comply with environmental regulations. One tool that can be used for the evaluation of energy efficiency in heavy-duty vehicles is the evaluation of energy efficiency using vehicle modeling and simulation. Simulation provides a path for energy efficiency improvement by allowing rapid experimentation of different vehicle characteristics on fuel consumption without the need for costly physical prototyping. The research presented in this paper focuses on using real-world, sparsely sampled telematics data from a large fleet of heavy-duty vehicles to create high-fidelity models for simulation. Samples in the telematics dataset are collected sporadically, resulting in sparse data with an infrequent and irregular sampling rate.