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• The data collected from three trails is available as an excel document.
• There is a correction factor for the water heights because the first hole isn't at the bottom of the bucket. There is an offset of 3.5 inches. Also the lengthy decimals result from using english units with eights and sixteenths inches.

SO when i acidentally redirected this page to another website through a mistake in programming Aaron Hamid helped me out. In order to undo the problem he determined the pageId of the page by using the page-info macro on a different page, and then manually entered the page edit url (https://confluence.cornell.edu/pages/editpage.action?pageId=79299719) to edit the page and remove the redirect.

Results

The Riser Pipe is a Good Approximation of a Linear Weir

Experimental data

Figure 1: The graph shows the height versus flow rate data for the three experimental trials and the predicted data. The original graph is available here
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Figure 2: The graph shows the flow rate versus height data for the three experimental trials and the predicted data.The original graph is availabl here
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• The experimental data from the three trials have high similarity to one another. This shows consistency in the experimental set-up.
• There is some discrepency between the predicted values and the experimental values.

Figure 3:The graph below show the differnce between the predicted height and the recorded height as a function of water height.The original graph is available here
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Figure 4: The graph below show the percent deviation between the predicted height and the recorded height as a function of water height. The equation used to create the data is Image Added.The original graph is available here
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Possible Causes of Discrepency

1. Accuracy of the flow meter installed in-line at the pilot plant. The readings may be inaccurate.

• Research into the flow meter specifications showed guaranteed accuracy up to 0.25% of the flow rate.
• Data taken manually to determine actual flow compared to the flow meter is not significantly from the flwo meter to suggest problems with the flow meter.

  Flow Meter Reading, GPM	Actual Flow Rate, GPM	% Deviation
  4.6	4.69	1.97
  6.1	6.25	2.51
  7.4	7.53	1.85
  11.1	11.62	4.71

• Flow meter accuracy not the problem.

2. Problems with the orifice equation approximating the head loss on a vertical orifice, the equation was designed for a horizontal orifice. May need to integrate to find the head on the holes as a function of height, would lead to changes in construction of the riser pipe.
3. The percent deviation graph show a constant percent deviation as the flow rate increases of about 10% after an initial spike due to the effect of small errors on small value readings. The errors seen at the upper limits aren't extreme, they are consistent with the other deviations.

Conclusions

The design for a flow measurement device was tested. A riser pipe with a pattern of holes was used to restrict the flow so the height of water in the entrance tank of a water treatment plant directly correlates to the flwo through the riser pipe. Three trials were undertaken to determine if the system of holes reliably and accurately approximates a sutro wier. As long as a system can be devised to prevent the clogging of holes during operation the riser pipe is an effective tool. The riser pipe entrance tank sytem provides data on flow with an accuracy of approximately ten percent.Scientific Paper Rough Draft