Beginning from the mid-70's a clear trend emerged in car aerodynamic design and styling which dictated the lowering of the hood profile and a corresponding reduction of grill openings, while the nose surface remained dedicated to the bumper impact area and car number plate. On the other hand the increasing power of the engines requiring the treatement of exaust gases, increased air conditioning system diffusion, combined with a front wheel drive layout, have all acted to crowd under-hood space, making the cooling problem more complicated than ever.
The aim of this paper is to demonstrate that an aerodynamic approach oriented to low drag coefficient is not in conflict with good cooling efficiency.
To do this on existing modern car models different front modifications were applied: air duct, opening displacement in a more favourable area, structural modification to carry bumper loads etc. Through these improvements substantial gains in drag reduction, virtually with the same cooling effectiveness, were obtained.