AERODYNAMIC AND REPAIRABILITY CONSIDERATIONS IN TRUCK CAB AND BUS BODY DESIGN

The main factors affected by aerodynamic performance are operating costs and vehicle safety. Scale models have been used in wind tunnel tests to ensure that good aerodynamic performance is obtained without significant conflict with other areas of design. Drag, which is proportional to the square of the velocity, is the critical factor affecting operating speed. Major changes in drag result from the different airflow characteristics around the cab shape. It was found that the most efficient cab shape allowed the airflow to remain attached to the cab surface. Tests showed that the roof flow had the most significant effect and could add 40 per cent to the drag coefficient. Other factors investigated included the shape of the cab sides and the valance. Drag features of different load types and vehicle builds were studied to assess the effect of cab design on the vehicle as a whole. Different results were given for low and high loads. A combination of good cab shape and a deflector were needed for high loads. Recommended design shapes are discussed. The author shows how relatively small design changes could give significant cost savings in repairs. The repair of a severely damaged Leyland national bus is given as an example. /TRRL/

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  • Corporate Authors:

    Embankment Press Limited

    Building 59, GEC Estate, East Lane
    Wembley, Middlesex HA9 7TQ,   England 

    Embankment Press Limited

    Building 59, GEC Estate, East Lane
    Wembley, Middlesex HA9 7TQ,   England 
  • Authors:
    • Lowe, W T
  • Publication Date: 1977-5

Media Info

  • Features: Figures; Photos;
  • Pagination: p. 19-23
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00163826
  • Record Type: Publication
  • Source Agency: Transport and Road Research Laboratory (TRRL)
  • Report/Paper Numbers: Analytic
  • Files: ITRD, TRIS
  • Created Date: Dec 27 1981 12:00AM