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The measurements were taken at 4 different points along the manifold, separated into at close to fourths as possible given the interference of bolts protruding from the walls of the flume. For each port, we manuevered maneuvered the ADV in front of each port until we thought we were in the the peak portion of the flow. We recorded data for 1 minute and then moved the ADV 1 cm to the left and 1 cm to the right of our first recording point to ensure that we captured the peak flow. We collected data at these points for 1 minute also.
In the analysis of our data, we took the mean of the velocities at each port for all 3 (and sometimes 4) measurements. Then we plotted the velocity profile for each port, assuming a Gaussian profile, and estimated the maximum flow rate at each port. These calculations were than plotted along the length of the manifold to give a velocity profile for the uniform manifold setup.
Results & Discussion
The results of our first experiment for a uniform manifold were not what we expected. Due to the expectation of pressure recovery dominating major losses (friction inside the manifold) we had expected the velocity coming out of the ports to actually increase along the length of the manifold. However, once the maximum velocity for each port was plotted against its distance down the manifold (see graph) it seemed that just the opposite trend was true. The velocity appeared to have peaked early on in the manifold and then gradually decreased after that.