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Linearization and Calibration

Introduction

Presently, the The Flow Controller device is being utilized used to create maintain a constant head tank, where the water level level of water in a source, a constant head tank remains constant, being which is refilled by a stock tank. This By adjusting the constant head tank is the measuring point for the head loss which governs the flow rate of Alum into the plant. However when implemented in the field, it has become increasingly apparent that there are one or more confounding variables that are rendering our equations inaccurate, causing for , different flow rates of Alum may be sent to the plant for the flocculation process. Field use of this device, however, is consistantly inaccurate, diverging in direction relation to flow rate as well as tubing length. However, the majority of the data seems to indicate that are are infact more confounding variables which make flow predictions nearly impossible. This dependence on faulty information, namely the inapplicable equations, may cause miss-dosing in the plant , reducing efficiency and at times creating wasteful and less than optimal performance in the communities.or a wasteful situation of using too much Alum for the plant.

Divergence specifically occurs to cause under delivery of alum to the plant, which decreases the efficacy of flocculation and has an adverse affect on effluent turbididtySpecifically, in tests that have been conducted in Honduras and the United States, flow rates at greater head losses are experimentally producing lower flow rates than expected through mathematical modeling, indicating that the flow control module is not functioning exactly as theorized. This section of the Flow Control Module Team is conducting tests to identify confounding variables to more accurately render parameterize the equations to provide for more efficient flocculation in the plant.

Goals

This project section is attempting to resolve the mystery of where inconsistencies arise that cause deviations from the standardized equations that relate head loss and flow rates which are used to dose the flow of the water treatment plant. There are a few variables that we hope to test. First we need to assure our selves that the flow control module is actually operating within the laminar flow range, rather than prematurely transitioning to the turbulent flow range. After this, we will look into the affect of tube length on the flow, as well as evaluating the possible affect that the length of the tube in question has on the dosing flow that is being modeled. After this, the question of additional sources of head loss will be considered, the possibility of manufacturing in accuracies or possible the inclusion of constants based on the mechanismteam is working specifcially with the constant head tank as a distribution system with known parameters and an adjustable arm for dosing providing a known head loss from elevation. First it is important to verify that the tubes in use do, in fact, meet the specifications of smoothness and diameter. Once we are sure that the material is regular, and if not, once we may correct for this difference, it is important to see what the trend is in divergence from the Hagen-Poiseuille equation. Graphing of flow rate vs. Headloss allows for a simply relationship between the experimental and theoretical. Once these have been parameterized for the purposes of calculation, it will be useful to continue looking into possible sources of headloss through the system or any factory that may deter flow.

Linearization and Calibration team goals and meeting minutes.

Methods and Results from Specific Experiments

Flow Rate vs. Headloss for variable Tube Lengths
*Taking the new aparatus, flow rates were calcualted relative to head loss and plotted again the Hagen-Poiseuille equation to anazlye divergence from the mathematical model

Diameter Corrections
*Calculate the inner diameter of the black tube used for dosing to ensure accuracy in dosing

Float valve corrosion test

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• Background on previous research

Conclusions

Based on the research that has been donework so far, it may be concluded that the flow control module is prematurely transitioning into turbulent flow, causing inaccuracies in the calculated flows. We hope to continue testing, modifying different variables to find the source of the inaccuracythere are variables that are causing significant distortion between experimental and theoretical results. Also, this may be attributed to manufacturing, due to its strongly correcting aspect interms of the equations.