Guy L. Larose

Further aerodynamic studies of Lions’ Gate Bridge – 3 lane renovation

Abstract This paper presents the results of aerodynamic studies of the Lions’ Gate Bridge – 3 lane renovation. The studies are divided into two parts: In the first part results of wind tunnel tests on a section model are compared to the results from two-dimensional numerical simulations based on the discrete vortex method. In the second part, changes in aerodynamic behaviour due to design revisions and changed mass and stiffness properties are studied by means of numerical simulations only. This was made possible because the numerical simulations had been calibrated with the results from wind tunnel testing in the first part of the studies and compared favourably. The numerical simulations proved both time and cost efficient. The studies undertaken are exclusively for the renovation of the suspension bridge.

An experimental study of the aerodynamic influence of a pair of winglets on a flat plate model

The influence of a pair of thin stationary winglets on the aerodynamics of a bluff body is studied in this paper. The bluff body in question is a rectangular prism with a width-to-depth ratio of nine, and is referred to as a flat plate. The aerodynamic and aeroelastic characteristics studied experimentally were the static aerodynamic force and moment coefficients, their rate of change with angle of wind incidence and the motional aerodynamic derivatives. It was observed that a pair of winglets placed directly above the leading and trailing edges of the rectangular prism improved its aeroelastic characteristics. The winglets provided important aerodynamic damping and reduced the sensitivity of the rectangular prism to torsional aerodynamic instability. The experimental approach and a summary of the main findings are presented.

Steady and Unsteady Surface Pressure Distributions Around Rectangular Prisms With Sharp Edges at Reynolds Number Up to 2.5×106

The commonly-held assumption that the aerodynamics of rectangular prisms with sharp edges are insensitive to Reynolds number is shown to have limitations. Flow reattachment on the top and/or bottom of the prisms can be related to Reynolds number, Re. Steady and unsteady surface pressure measurements were carried out on nine different rectangular prisms for Re from 0.3×106 to 2.5×106 at several angles of attack, in smooth and turbulent flow. It was observed that the reattachment was dependent on parameters such as fineness ratio, edge treatment, angle of attack, turbulence of the oncoming flow and Reynolds number. Permanent reattachment occurred for prisms with fineness ratio of 4 and fluctuating reattachment took place for rectangular prisms with fineness ratio as low as 2.Copyright