Method for a Low Cost Hydrokinetic Test Platform: An Open Source Water Flume

While educational wind tunnels are common place for instruction and experiments in fluid mechanics, they generally do not possess the capabilities to perform hydrodynamic testing. This paper will present the work by the authors to develop a water flume that would allow hydrodynamic testing at velocities up to 2.0 m/s. The flume was constructed by an undergraduate and at a cost lower than commonly available commercial units. Both the fabrication process and the potential experiments that the flume could house are designed to improve student learning in the area of fluid mechanics. The design is developed to be relatively compact, with a 7’x3.5’ footprint and utilizes a commonly available single-stage centrifugal pump. Flow velocities in the test section can be varied passively by changing the insert containing the test section and actively with a recirculation valve. The total cost for this project was approximately $3500 and required 3 months of part-time work to construct. Flow velocity measurements in the test section were made by simple flow visualization and found velocity ranged from 0.32-0.65 ft/s within a 6”x12”x12” test section. The water flume was subsequently used by a senior capstone project for testing of their water turbine. Student self-evaluations were used to assess whether their experiences reinforced fluid mechanics concepts and developed their skills in experimental fluid mechanics. The results show that the students believed their work with the water tunnel strongly met the learning objectives in the area of experimental methods and somewhat met in the area of concepts. Although the data set was small (5 students), it does show promising correlations that highlight the potential of the water flume in an engineering educational environment.