Comparison of aerodynamic drag determination procedures for HDV CO2 certification

This paper summarizes and compares the two main test methods for aerodynamic evaluations of heavy trucks in the United States and the European Union: coastdown testing and constant-speed testing, respectively. The methodologies were compared in terms of their instrumentation requirements, test-track requirements, testing effort, data analysis and use within simulation tools, precision, and accuracy. Both methods have relative advantages and deficiencies.