Influence of the air diffusers on human thermal comfort inside vehicles – a review article

Abstract

The time spent by vehicle occupants in traffic has grown significantly in the last decades. Improving the thermal comfort of the people inside vehicles has gained a lot of importance in the last years both from subjective and objective reasons. The airflow passing through the air diffusers will directly affect the thermal state of the users through its temperature, velocity, and turbulence. A solution to improve the cabin ambiance is to uniformize the airflow inside vehicle through a better mixing between fresh air and ambient air. The automotive industry through its vehicles produced in the last years does not seems to consider this innovative strategy. An idea to improve the air mixing by passive means is using innovative air diffusers which have the capacity to entrain more air than a regular air diffuser. The lobed shaped cross orifice was found to entertain more air than a regular nozzle and derived from this shape more geometries emerged. A good compromise for the air diffuser design in vehicle was found to be the lobed ailerons. The entrainment in the case of the airflow issued from the air diffuser with lobed ailerons it was found to be greater than in the case of the standard air diffuser with straight ailerons.

Innovative High-Induction Air Diffuser for Enhanced Air Mixing in Vehicles and Personalized Ventilation Applications

“…High-induction air diffusers with lobed orifices are a promising solution for improving IEQ in vehicles [27]. The same conclusion was pointed out in [28], where these air diffusers supply fresh air into the ventilated enclosure and mix it with the existing ambient air, thereby lowering pollutant levels and enhancing the overall IEQ. The idea of using lobed orifices in ventilation in terms of high induction is not new.…”

Numerical study on high induction air diffusers for improved indoor environmental quality in vehicles

“…Because of this, experts and researchers in the HVAC area are continually searching for new ways to improve the comfort conditions inside vehicles at the same time without increasing energy consumption of the automobiles, especially in the new context of electrically powered vehicles, where each energy saving is directly translated in the increase of the vehicles range [9][10][11][12][13][14].…”