2026-10-09T21:36:07Z https://api.figshare.com/v2/oai

oai:figshare.com:article/31342786 2026-09-23T07:39:10Z category_26260 portal_753 item_type_3 month_year_09_2026

Relationship between vehicle cabin thermal conditions, passenger thermal comfort, and air-conditioning energy consumption Kefitlhile Githinji (23056108) Automotive engineering not elsewhere classified Occupant Comfort Thermal interaction Ventilation airflow HVAC Energy Efficiency Predicted Mean Vote (PMV) Electric vehicles (EVs) Climate control strategies Energy consumption reductions SDG 3 Good health and well-being SDG 7 Affordable and clean energy SDG 13 Climate action <p dir="ltr">This research investigates the relationship between vehicle cabin thermal conditions, passenger thermal comfort, and air-conditioning energy consumption under varying airflow rates. The study examines how occupants perceive and physiologically respond to changes in cabin temperature during short driving scenarios, with a focus on identifying airflow strategies that balance comfort with energy efficiency.</p><p dir="ltr">Human subject experiments were conducted in a controlled vehicle environment using three cooling airflow rates (0.02 kg/s, 0.03 kg/s, and 0.04 kg/s). Participants were exposed to repeated cycles of air-conditioning activation and deactivation while reporting key comfort milestones, including the time to initial discomfort and time to maximum discomfort. These subjective responses were paired with objective measurements of cabin air temperature, seat temperature, vent air temperature, floor-level air temperature, and mean skin temperature.</p><p dir="ltr">Thermal sensation was quantified using Predicted Mean Vote (PMV), allowing comparison between perceived comfort and physical cabin conditions across six experimental response stages. The study further models hypothetical air-conditioning energy consumption using compressor power data to evaluate the trade-off between maintaining thermal comfort and conserving energy.</p><p dir="ltr">Results show strong inter-individual variability in thermal tolerance, with airflow rate significantly influencing both the timing and distribution of discomfort onset. A moderate airflow rate of 0.03 kg/s consistently delayed discomfort, stabilised mean skin temperature, and achieved neutral PMV values during cooling, while also requiring less cumulative energy than higher airflow settings. Lower airflow resulted in rapid comfort degradation, whereas higher airflow produced diminishing comfort benefits and increased variability in participant responses.</p><p dir="ltr">By integrating physiological data, subjective comfort reports, cabin temperature measurements, and projected HVAC energy usage, this research provides a quantitative framework for evaluating adaptive vehicle climate control strategies. The findings highlight the limitations of static airflow settings and support the development of intelligent, personalised HVAC systems that dynamically balance occupant comfort with energy efficiency, particularly in hybrid and electric vehicle platforms.</p> 2026-09-23T07:39:10Z Dataset Dataset 10.25403/UPresearchdata.31342786.v1 https://figshare.com/articles/dataset/Relationship_between_vehicle_cabin_thermal_conditions_passenger_thermal_comfort_and_air-conditioning_energy_consumption/31342786 CC BY 4.0