Search Results

Maintaining thermal comfort is one of the key areas in vehicle HVAC design wherein airflow distribution inside the cabin is one of the important elements in deciding comfort sensation. However, the energy consumption of air conditioning system needs to stay within the efficient boundaries to efficiently cool down the passenger cabin otherwise the vehicle energy consumption may get worsened to a great extent. One approach to optimize this process is by using numerical methods while developing climate systems. The present paper focuses on the numerical study of cabin aiming and cabin cool-down of a passenger car by using computational fluid dynamics (CFD). The main goal is to investigate the cabin aiming with a view to figure out the minimum average velocity over the passengers at all vent positions. Cabin aiming ensures substantial amount of airflow reaches to the passengers as well as every corners of the cabin across the wide climatic range.

Adequate visibility through the vehicle windshield over the entire driving period is of paramount practical significance. Thin water film (fog) that forms on the windshield mainly during the winter season would reduce and disturb the driver’s visibility. This water film originates from condensing water vapor on inside surface of the windshield due to low outside temperatures. Primary source of this vapor is the passenger’s breath, which condenses on the windshield. Hot and dry air which impinges at certain velocity and angle relative to the windshield helps to remove the thin water film (defogging) and hence improves driver’s visibility. Hence a well-designed demisting device will help to eliminate this fog layer within very short span of time and brings an accepted level of visibility. An attempt is made here to design and develop a demisting device for a commercial vehicle with the help of numerical and analytical approach and later on validated with experimental results.