Flow Controller Calibration, Summer 2008

Introduction:

The flow controller design tool on the Flow Controller page is used to calculate the tube length necessary to achieve a desired flow rate with a certain head loss. It has been observed that the actual flow rates that occur when using the lengths of tube provided by the design tool were consistently much slower than they theoretically should have been. This indicated that there was some problem with the assumptions made by the design tool. The error was most likely due to one of two things. It was possible that the actual diameter of the tubing being used was slightly smaller than the diameter published by the manufacturer, or that there were significant minor losses in the flow controller not being taken into account by the assumption of a linear relationship between flow rate and head loss/tube length. It was decided that rather than having to manually calibrate every new flow controller, it would be better to come up with a new method for finding the tube length needed. The new method would need to take into account the smaller diameter of the tubing and/or the minor losses, and would predict a more accurate flow rate without having to do further manual calculations or having to cut the tube after construction of the flow controller

Filter Flow Control - Spring 2017

Matt Cimini, Alex King, Tanvi Naidu

Abstract:

The objective for the Filter and Treatment Train Flow Control team (FTTFC team) this semester was to design and construct a weir module that would allow the plant operator to easily redirect sucient flow for filter backwash without shutting o↵ other filters’ flow. The goal of the design was to be easily constructible, easy to operate, strong enough to withstand water pressure and require no calculations for plant use. The team designed several removable weir options and ultimately chose a hinged design. The design is similar to a dog door that will be shut during normal flow and open during backwash. The model was fabricated and tested under conditions simulating a 20 L/s plant. The weir module was strong enough to withstand the flow, was easy to construct and was simple to open and close even with the water pressure against it and therefore was a success. There was some significant leakage around the weir flap. Therefore, construction and design should focus on recommendations for watertightness of the flap if this design is to be used in an AguaClara plant in the future.

Ram Pump - Fall 2019

Ching Pang, Alycia Storch, Payton Hunter

Abstract:

Previous Ram Pump teams have created mathematical models describing velocities, forces, flow rates, headlosses, etc. in the AguaClara Vertical Ram Pump (ACVRP); performed experiments to learn more about what actually happens in the system; and have made redesigns to the setup and ACVRP itself to further improve its efficiency, likeliness to an AguaClara plant, and to increase the ease of assembly and adjustment. This semester the team plans to fabricate a new lab setup that integrates the setup into the work bench for a redesign of the ACVRP, and to further explore ways to improve its efficiency. The team has decided on a new design that eliminates the bottom check valve of the ACVRP and the threaded rod and compression spring that it housed and instead includes an extension spring that will be at the top of the head tank. The extension spring will be connected to a hook on the top of the plate with metal wire rope. It is expected that the functionality and process of the ACVRP will not change but making fine-tune adjustements to the initial and final forces of the spring will be easier to make because there will be easier access to the spring. The team created a materials list for the new parts needed and is currently updating the CAD model to reflect the changes. The team plans to construct the new lab setup and ACVRP design and then to perform experiments as well as improve theoretical equations to further optimize the ACVRP.

Fabrication: Constant Head Tank - Spring 2016

Anna Doyle, Valerie Shao, Serena Takada

Abstract:

The main problem with the plastic Tupperware Constant Head Tank (CHT) containers currently used in the the AguaClara water treatment plants is that they are not chlorine resistant so they have to be replaced frequently. This issues was addressed by the fabrication team this semester. New CHTs were designed, fabricated ,and evaluated to determine the best to be implemented at AguaClara treatment plants. The first design was fabricated from clear PVC sheets and constructed using PVC welding; the second was constructed out of a PVC pipe and cap. The two designed were then compared in terms of ease of construction, functionality, and costs. Based on this analysis and the recommendations from the AguaClara engineers, the second design was determined to be the best and will be implemented in future AguaClara water treatment plants.

Chemical Dose Controller - Spring 2017

Annie Cashon, Cynthia Chan, Susan McGrattan, Karan Newatia

Abstract:

The Chemical Dose Controller (CDC) system was designed to maintain a constant chemical dose to the treatment train as the plant flow rate and influent turbidity change. This semester, the CDC team worked on expanding the modular design from previous semesters in order to improve ease-of-use during operation, better access to the system for plant operators, and greater system efficiency overall. The team designed and fabricated a new and improved constant head tank and calibration columns systems. This semester the CDC team also collaborated with the 1 L/s plant sub-team to create a CDC system for low flow rates.