AbstractsEngineering

Using air recirculation inside a vehicle is an effective way to minimize particle pollution and to maximize air conditioning cooling performance, however, prolonged use of air recirculation can cause high levels of carbon dioxide due to occupant exhalation and the lack of fresh air. Using air recirculation strategies can be an effective way of mitigating high carbon dioxide concentrations and poor air quality. Using AMEsim software, this study created a lumped parameter model to predict carbon dioxide concentrations, and analyzed the effects that various recirculation strategies had on the compressor load savings, carbon dioxide concentrations, and thermal environment inside the cabin. Results found fractional and on-off strategies to be effective ways of maintaining carbon dioxide concentrations below 1100 ppm, while timed control strategies produced unacceptable average concentrations above 1200 ppm and 3500 ppm for 1 occupant and 4 occupant scenarios under various driving cycles, consequently resulting in poor air quality.