Obtaining drag force from pressure distribution

AI Thread Summary
To obtain the drag force on a smooth cylinder in a wind tunnel, pressure measurements were taken at regular intervals around the cylinder. The data, recorded in inches of water, along with known freestream velocity and stagnation pressure, were analyzed. The drag coefficient calculated for the large cylinder was approximately 0.71, while for the small cylinder, it was around 1.07. The process involved calculating the pressure coefficient (Cp) at measurement points, multiplying by the cosine of the angle of rotation, and integrating the results. This method effectively provided the necessary values to determine the drag force.
IrishAlex
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I'm trying to obtain the drag force acting on a smooth cylinder at the exit plane of a wind tunnel. I took measurements of pressure at regular degree intervals around the cylinder.

The pressure readings are in inches of water, and I know the freestream velocity and the stagnation pressure. I just don't know what to do with the data I have to obtain a value for drag force.
 
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Thanks for all your help. I found Cp at all the points of pressure measurement, multiplied by cos of the angle of rotation, plotted the product versus angle of rotation and integrated from 0 to pi.

Turns out the drag coefficient for the large cylinder is about 0.71 and 1.07 for the small cylinder.
 
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