https://thesis.library.caltech.edu/1265 ... a_1993.pdf -- it has eight chapters. Continuing forward anyway, I drew a small (one square foot, .0929 Sq M) plate on the ground with a 100 MPH (44.7 M/sec) wind, using Thomas Schrader's parameters for 'Flow Around A Car'. I'm not sure if those same parameters can be used with different wind velocities. With a Cd of 1.28 I was expecting 32.76 lbs per sq ft (159.95 Kg/Sq M).
After running a simulation I got 29.72 lbs per sq ft (145.09 Kg/Sq M). I sort of assumed that the slippage around the edges would be about the same measurement on a small plate or a big plate, but proportionally greater on a small plate, which would possibly explain why the drag was less than expected. So I drew a larger plate (On the ground, 100 sq ft, 9.29 Sq M 100 MPH wind 44.7 M/sec). Expecting 32.76 lbs per square foot ( 159.95 Kg/ sq M), now I got 34.79 lbs per sq ft (194.25 Kg/Sq M). So then I thought maybe it's greater than expected because it's on the ground and there is no slippage around the bottom edge. So I drew a suspended, one sq ft (.0929 Sq M, 100 MPH wind, 44.7 M/sec) plate. Again expecting 32.76 lbs/sq ft, now I got 26.84 lbs/ sq ft (131.03 Kg/Sq M). I thought possibly it is less than expected because all the edges are exposed to slippage. Then I drew a suspended 100 sq ft (9.29 Sq M) 100 MPH wind (44.7 M/sec) plate. I got 32.13 lbs per sq ft (156.85 Kg/sq M) which is the closest to the expected 32.76 lbs/sq ft (159.95 Kg/sq M). So I was wondering, did I make mistakes in the set up or is this a reasonable explanation of flat plate scale effect?
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