PROPER ORTHOGONAL DECOMPOSITION AND RECONSTRUCTION OF MULTICHANNEL ROOF PRESSURE

The proper orthogonal decomposition (POD) and reconstruction of pressu re on the roof of a low-rise building is described. The point pressure s acquired simultaneously at 494 taps, uniformly distributed on the bu ilding surface, were used in the analysis. The pressure space correlat ion was computed and employed to calculate the eigenvalues and eigenve ctors (modes) for two cases: roof pressure held (RP) and roof and wall s pressure (RWP). The first two of the RP modes were found to be respe ctively similar in shape to the pressure mean square and the mean pres sure derivative computed with respect to the wind direction. Strong in teraction between the wall and roof pressures was identified from the POD analysis. The POD results for the RP case were employed to reconst ruct the point and area-averaged roof pressure. Approximately 30% and 2% of the computed modes were needed to represent the largest negative peak of point and area-averaged roof pressure, respectively. Only one mode was sufficient to reconstruct the mean point and area-averaged r oof pressure.