Paper No. 30-8
Presentation Time: 9:00 AM-5:30 PM
WATER FLOW NET CHARACTERIZATION BY USING A TANK MODEL: PRELIMINARY OUTCOME
A model study was conducted to observe and characterize the flow of water through sandy soil. One of the most relevant tools used for characterizing groundwater flow is the flow net. Assuming that water is incompressible and there is zero volume change in the soil mass, it is known that the total rate of inflow is to equal the total rate of outflow. Thus, following the principle of flow continuity, we use the Laplace equation of continuity, to observe the concept of the flow net. Computing the flow through a miniature channel, we observed the total head difference from the first equipotential line to the last equipotential line divided by the number of equipotential lines between the first and last head drop qchannel=(k)(∆H)Nf/Nd. This resulted in multiplication of the permeability by the head difference 1.9 inches by the number of flow channels 4 divided by the number of equipotential line drops 6. Being that this is the scenario, Darcy’s Law is then substituted. This was done by multiplying the hydraulic conductivity by hydraulic gradient to find the velocity. The tank model has been designed to display the flow of groundwater around an obstruction. This model clearly illustrates the flow path and velocity of the groundwater. Constructed with sheets of glass glued together to seal and prevent leakage. A submersible pump was connected to a clear vinyl tube, which is attached to the apparatus with silicone sealing glue, allowing for a constant difference of pressure while the water flows from one side to the other. The apparatus was leak tested prior to the soil being added. The pumps on each side are attached to a bucket of water below to prevent water from over flowing or drying out the soil. As the groundwater flows, traces of the dye which represent the flow lines, or stream function, provides evidence of the water’s flow nets. Overall, it provides a simple approach to understand the practical aspects of groundwater flow.