ORVM Based Cabin Thermal Comfort - A Technological Approach

Enriched ventilation and driver assistance systems which plays vital role in human thermal comfort and safety, are now necessities for the whole automotive sector. For faster cabin thermal comfort, air circulation around occupant’s body reveals higher cabin comfort index. In India natural and forced ventilation system is predominantly used in commercial vehicles as an economical solution for achieving interim cabin comfort over air conditioning system. Presently used forced ventilation system consist of electrically driven blower motor to remove stale air around human body which is adding alternator load and thus affects fuel economy. Remarkably, 22% of such auxiliary electrical load is taken by electrical components from engine generated power.

In order to enhance cabin thermal comfort and conceivably reduce power usage, an effective air flow control system is need of hour. In the proposed new technology, the ORVM (Outside Rear View Mirror) based air cooling technique is used for cooling ambient air. The concept demonstrates the use of air against vehicle speed is directed through ORVM causing air cooling using direct evaporative cooling techniques. The cooled air is then passed to cabin for occupant's comfort. The concept is validated using virtual analysis tools for air flow analysis and air temperature drop at various vehicle speeds. The prototype model is prepared and tested by running vehicle on highway. The experimental analysis shows a temperature drop between 4.5 °C to 8°C over ambient air temperature and vehicle speed. The concept is also evaluated for drag forces to analyze effect of change in ORVM area on fuel economy. The extreme features of cooling the outside hot ambient air using matured cooling technology and dust filtering inside ORVM casing makes idea innovative and easily adoptable.