wind load evaluation on photovoltaic modules with flow deflector
abstract
the wind load on a photovoltaic system and the effects of adding a flow deflector around
the panel are studied. the deflector is a reinforce measurement aiming to reduce the
aerodynamic wind loads over the pv system, which can lower the collapsing risk when the
system is under extreme weather conditions. simulations of wind flow over both standalone and arrayed pv modules are performed by using the sst k-w turbulence model
based on the reynolds-averaged navier-stokes equations. the inlet velocity profile is
specified to describe the conditions representing the flows over a pv system located on a
large open terrain with the atmospheric boundary layer. the calculations are compared to
the data from the published wind flow simulations of the drag and lift force coefficients
along the centerline of the module, and to the net pressure coefficient on the pv module.
further, the wind load over the pv system are compared for both stand-alone pv module
and arrayed pv system with and without a flow deflector placed around it. the effects of
the wind directions, the pv module inclination angles, the shapes of the deflector, and the
spacings between the deflector and the module are investigated. the results show that when
the inclination angle of the pv module is fixed to 25°, placing the deflector around the
stand-alone module can generate a wind load reduction of up to 40%. for an arrayed pv
system, the wind load is reduced by 8% on the first-row modules under the wind direction
of 0°. thus, the deflector offers an economical solution for reducing the wind load on the
existing pv projects without modifying the modules or installation arrangements.