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Then, head loss through this system is calculated given the user-inputted value for the wall thickness of the desired PVC cap. These calculations utilize the fluids functions found at the top of this page. This head loss is composed of major losses, and hence shear losses, only. It should be noted that the head loss through the system did not include the head loss through the attached tubing. The diameter of the tube was relatively large and the length was generally short; therefore, we concluded that the head loss experienced through the tube would be negligible compared to that through the PVC cap orifice.
Using this information, the necessary flow of alum from the doser based on dimensions given above is determined. Using a required dose concentration of 1.5 mg/L in the untreated water, the necessary stock concentration located in the alum doser can be calculated.
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