Acknowledgements : Special thanks to, Dr. Mario Gomes EPA P3 Professor Ed Hanzlik

1. P-12462 Tow Tank for tethered hydrofoil Objective: The objective of the project was to build a small scaled version of tethered hydrofoil to compare with a simulation provided by Dr. Mario Gomes in MATLAB. Team P12462’s goal was to create a tow tank capable of moving a platform at a constant specified speed over the top of a stationary body of water in order to recreate a river flow passing over a hydrofoil. Concept Selection: Project Outcome: • Brainstorm: • Proposed concepts for the tank materials. • Wood structure and wood panels • Steel structure and wood panels • Steel structure and steel panels • Proposed concepts for rails and cart • Angle iron rails and skate bearings • 80/20 linear motion system • Machined bottom supported rail Concept Evaluation: A table was created to evaluate each set of concepts. Every concept was used as datum and compared to all other possibilities. The options where ranked taking into consideration and giving a different weight to every stake holder. Analysis of Tank: Model of Cart Design Picture of Actual Cart The ANSYS analysis was done using a hydrostatic force assuming the tank was completely full. The tank wall was supported on the side edges as well as the bottom faces. Meshing was done using a body mesh of 0.50 in (1.27 cm). Stresses, as well as total deflection were calculated. Structurally the tank has a factor safety of 20 with a yield strength of 50 ksi (345 Mpa). The tank also has a factor of safety of 9 for deflection, with an acceptable deflection of 0.03125 in (7.94e-4 m). The next analysis was done to account for outside forces acting on the tank walls. A point load of 200 lbf (889.64 N) acting in the same direction as the water was applied to the weakest point of the static analysis. Results showed that the tank does not yield and the design was acceptable. ANSYS Results for Deflection Model of Tank Assemble Design ANSYS Results for Stresses • Selected Tank Design: • 3/8 in (9.525 mm) thick, 2” SQ. (5.080 cm) Angle iron • 1/4 in (6.350 mm) thick, 2” SQ. (5.080 cm) Angle iron • 3/4 in (19.050 mm) thick Plywood • 16 feet (4.877 m) long 80/20 Aluminum • 3/4 hp (559.270 w) Motor • 1/16 in (1.588 mm) diameter Aircraft Cable • 6 in (15.240 cm) diameter Pulleys • Engineer Specs of Tank: • Tanks dimensions: 16 feet (4.877 m) long, 2.5 feet (0.762 m) wide, and 2 feet (0.610 m) high. • Max cart towing velocity: 3.21 ± 0.10 ft/s (0.950 ± 0.025 m/s) • Max volume of water: 599 US gallons (2,265 L) • 2 modular pieces, capable of being disassembled, moved, and reassembled by 2 people Picture of Actual Tow Tank Cart speed needed to be tested to confirm accuracy of LabVIEW control. Effective Pulley Diameter was an input usedto match measured speeds to expected speeds. Future Improvements: 1) Upgrade the plastic liner to a more durable material. 2) Upgrade tow cable and/or drive pulley. 3) Place windows in the tank walls to allow in water visibility. 4) Upgrade the plywood panels (walls) to sheet metal panels or glass panels 5) Improve rail mounting to tank Example of specification verification • Acknowledgements: • Special thanks to, • Dr. Mario Gomes • EPA P3 • Professor Ed Hanzlik • Professor John Wellin • Mr. Rob Kraynik • Mr. Jan Maneti • Mr. Dave Hathaway • Dr. Steven Day From Left to Right: Tim Buckner (ME), Hope Alm (ME), William Lentlie(ME), Shauna Traxler (ME), and Andres Santizo Matheu (ISE)