Pii: 0167-6105(84)90047-3

Spatio-temporal measurements of a fluctuating pressure field acting on the side faces of a square prism of finite height in boundary-layer flows are presented for 0 ° angle of attack. Two typical neutral atmospheric flow conditions were simulated in the wind tunnel to represent open country and urban flow environments. The fluctuating pressure field data allowed computat ions of the mean and r.m.s. (root mean square) pressure coefficients, power spectral density, autocorrelations, co-spectra, cross-correlations, orthogonal eigenfunction expansions and statistical dependence. Increased levels of turbulence in the incident flow have a marked influence on the fluctuating pressure field, through modifications which take place in the structure of the separated shear layers. The periodic vortexshedding process is vitiated in the presence of high levels of turbulence intensity in the incident flow, resulting in redistribution of the energy associated with pressure fluctuations over a wider frequency range.