This week, we devoted most of our testing time to investigating the effect of varying pumping speed, as well as the height of our chlorine source relative to our water source. We found that slower pumping speeds resulted in higher downstream chlorine doses across our three prototypes (the venturi, the T, and the tube-in-pipe). Our tests in which we varied the chlorine height were less conclusive.
Our objective with these tests was to determine which of our three models provided the most consistent dosing despite anticipated variations in our system, such as differences in pumping speed across different users. Surprisingly, we found that there was little difference between the tube-in-pipe and T models. The only difference between these designs is an extra T-pipe located where the chlorine tube feeds into the water source. We therefore concluded that this T has a negligible effect on the dosing capabilities of our device, and was an unnecessary added cost for the final product. The venturi dosed slightly higher than the other two models, but unfortunately was not any more accurate/consistent despite its sleeker design.
Next week, the plan is to begin testing with chlorine to see if the patterns we’ve been seeing with our simplified setup actually correlate to realistic dosing levels. We will use these tests to evaluate the reliability of both the tube-in-pipe prototype (simplest) and the venturi (most advanced design) and decide from here which would be best to implement on-site in Dhaka for the summer.