Maysoon Sharif's Individual Contribution Page

Fall 2009 Contributions

Jeff and I have been working on a code to calculate the size of ports that need to be drawn into the bottom of the lower baffles. We built off of a drain time function that was already in the MathCAD files that calculated the drain time for a particular port size. We graphed several of the inputs to the function against each other to try to find obvious relationships between them. As a result, we discovered that when the port size and the valve size (the valve that drains the flocculator from outside the tank) are the same, the relationship between the number of "tanks" (spaces between lower baffles) and the drain time is linear. Realizing that as long as the port area is no bigger than the cross-sectional area of the valve, the size of the ports limits the time it takes to drain the flocculator. To simplify the calculation, we decided to set the area of the port equal to the area of the valve.

Given a drain time, a function was written to calculate the valve diameter using the existing drain time function. The new function iterates from the smallest possible diameter to the diameter that provides a drain time no greater than 110% of the given time. The smallest possible diameter is desirable, because it ensures minimal cost of design.

In writing the autoCAD code, much of the existing code was made more efficient to save ourselves time in returning drawings. Union functions were added to subtract groups of objects simultaneously. Also, we removed iterations that intended to calculate existing variables. Additionally, the baffles are no longer being drawn using the lamina program, but rather, the simple box function.

Our port code (floctankbaffleportscript) was made to draw ports on alternating sides of the lower baffles so that water does not drain linearly through the tank (thus not getting mixed properly.) In order to subtract these quickly, the baffles were unioned in addition to the ports themselves.

We restructured the AutoCAD scripts wiki page to be more descriptive. All of the AutoCAD scripts for the flocculator should now be up to date, including pictures.

Jeff, Julie, and I worked on the code for the horizontal flocculator. Generic variables for lengths and widths were used to calculate dimensions, allowing us to reuse the same code for both the horizontal and vertical cases. Also, most of the existing position calculations were converted into matrices of the same size so that the code would be loaded to handle both vertical and horizontal calculations. The position calculations for the baffles change (using an if statement) depending on whether the number of channels is even or odd. A code strictly for the horizontal case currently draws an accurate floc tank, but more work must be done to incorporate the decision variable between the horizontal and vertical flocculators so that a single file can be used to calculate positions and dimensions for either case.

Summer 2009 Contributions

So far this summer, we adjusted the flocculator ports so that they appear at the bottom of the inner walls rather than the top. This change was made because having ports at the bottom makes more sense from a structural perspective. The change also required us to reverse the up/down orientation of the baffles and reassign the appropriate lengths accordingly in the Flocculator 3 program. It also required that the last channel have one less baffle than the previous channel to ensure that the water can flow under the last baffle and up over the channel to the sedimentation tank. However, removing the last baffle in the last channel resulted in the wrong up/down orientation in that channel. The baffles in the last channel were then reassigned elevations and lengths as necessary.

We also wrote a new script in the floctank program (see Flocchannelslotscript below) to draw slots into which the baffles could be slipped. The slots were all required to extend to the top of the tank from the elevation of the corresponding baffle.

For certain flow rates, one or two baffles in the last channel were positioned in the midst of the exit channel to the sedimentation tank. The x-direction position calculations for the last channel had to be changed in this case. When one baffle ended up in the exit channel, the first baffle was made to be placed a distance of S.FlocChannel from the end of the exit channel. The remaining baffles are then spaced evenly in the allowable space. When two baffles ended up in the exit channel, those two baffles were removed and the remaining baffles are spaced evenly in the channel. Two baffles must be removed to maintain an even number, and also to ensure that the spacing in the last channel is greater than that of the channel before.

Pages Created

Floctankbafflescript

Flocchannelslotscript

Floctankbaffleportscript

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