HVAC automotive vents evaluation and their performance

Car passengers’ comfort is increasingly important, not only from good feelings or travel comfort point of view, but also from the transportation safety perspective, where the driver's thermal comfort is of crucial importance. The main components affecting optimal comfort are HVAC vents. This article focuses on the performance assessment of a side dashboard car vent with adjustable horizontal vanes that allow changing the air jet direction vertically along with a complete shut-off. A new measuring methodology is presented here; it simulates real and complete ventilation system conditions using a simple laboratory piece of equipment with a single vent mounted. The flow pattern as generated by the vent jet was first studied with smoke visualization, then using a two-wire constant-temperature anemometer probe. Jet orientations and boundaries were identified for particular vent settings, which are fundamental in the assessment of vent performance. The average air speed and turbulence intensity were determined. Results show that the actual jet direction differs substantially from the direction that was set by the vanes and that further research may lead to a new and improved design of automatic control of a zonal ventilation system and contribute to more accurate control of passengers’ comfort.

[1]  Eusébio Z. E. Conceição,et al.  Evaluation of comfort level in desks equipped with two personalized ventilation systems in slightly warm environments , 2010 .

[2]  P. Fanger,et al.  Perception of draught in ventilated spaces. , 1986, Ergonomics.

[3]  P. J. Baker,et al.  An Optimised Thermal Design and Development Process for Passenger Compartments of Vehicles , 2009 .

[4]  Edward Arens,et al.  Moving Air for Comfort , 2009 .

[5]  Wojtek Wlodarski,et al.  Car cabin air quality sensors and systems , 2006 .

[6]  Hidemoto Nakagawa,et al.  An automated car ventilation system , 2000 .

[7]  Sang Joon Lee,et al.  Investigation on the flow characteristics inside an automotive HVAC system with varying ventilation mode , 2009, J. Vis..

[8]  W. Snow,et al.  Ventilation of buildings , 1906 .

[9]  J. W. Wan,et al.  Influence of the position of supply and exhaust openings on comfort in a passenger vehicle , 2014 .

[10]  P. Fanger.  Assessment of man's thermal comfort in practice , 1973, British journal of industrial medicine.

[11]  Mariana Ivanescu,et al.  STUDIES OF THE THERMAL COMFORT INSIDE OF THE PASSENGER COMPARTMENT USING THE NUMERICAL SIMULATION , 2010 .

[12]  J. Toftum,et al.  Air movement--good or bad? , 2004, Indoor air.

[13]  David Peter Wyon,et al.  Driver Vigilance - The Effects of Compartment Temperature , 1992 .

[14]  D. Bharathan,et al.  Predicting human thermal comfort in a transient nonuniform thermal environment , 2004, European Journal of Applied Physiology.

[15]  Michael E. McCauley,et al.  A STUDY OF HEAT, NOISE, AND VIBRATION IN RELATION TO DRIVER PERFORMANCE AND PHYSIOLOGICAL STATUS , 1974 .

[16]  Chas B Dudley.  A System of Passenger Car Ventilation , 1904 .

[17]  D. Ruži.  IMPROVEMENT OF THERMAL COMFORT IN A PASSENGER CAR BY LOCALIZED AIR DISTRIBUTION , 2011 .

[18]  M C Gameiro da Silva,et al.  Measurements of comfort in vehicles , 2002 .

[19]  Kuo-Tsang Huang,et al.  Passenger thermal perceptions, thermal comfort requirements, and adaptations in short- and long-haul vehicles , 2010, International journal of biometeorology.

[20]  Barbara Griefahn,et al.  The significance of air velocity and turbulence intensity for responses to horizontal drafts in a constant air temperature of 23°C , 2000 .

[21]  P. Fanger,et al.  Air turbulence and sensation of draught , 1988 .

[22]  H. H. Bruun,et al.  Hot-Wire Anemometry: Principles and Signal Analysis , 1996 .

[23]  Hidenobu Okamoto,et al.  Determination of Flow Velocity Distribution in a Vehicle Interior Using a Visualization and Computation Techniques , 1991 .