Abstract:
In this research work, an experimental investigation of wind effect on Pentagonal
cross section was carried out. The test was conducted in an open circuit wind tunnel
at a Reynolds number of 4.22 x 104 based on the face width of the cylinder across the
flow direction in a uniform flow velocity of 13.2 m/s.
The test was carried out on a single cylinder at various angles of attack from 0° to
72° at a step of 9°. The surface static pressures at the different locations of the
cylinder were measured with the help of inclined multi-manometers. The wind
velocity was kept constant at 13.2 m/s.
The pressure coefficients were calculated from the measured values of the surface
static pressure distribution on the cylinder. Then the drag and lift coefficients were
obtained from the pressure coefficients by the numerical integration method. There is
significant drop in the drag coefficient values for the single pentagonal cylinder in
comparison to that of the single square cylinder. The variation of the lift coefficient
on the single pentagonal cylinder is shifted 90 and pattern is more or less similar with
the variation of the lift coefficient for the single square cylinder except at angle of
attack of 00. The results will enable the engineers and architects to design buildings
more efficiently. Since the results will be expressed in the non-dimensional form
they may be applied for the prototype building.
