An exercise is described that combines theoretical predictions and experimental measurements of gravity-driven pipe flow. This exercise is used to reinforce lecture material on viscous incompressible flows in a junior level thermal and fluids engineering course in a baccalaureate engineering technology program. The configuration studied consists of the flow of water through a length of small diameter tubing supplied by an elevated reservoir. The theoretical component of the exercise involves modeling the system using the incompressible energy equation combined with analytical models for viscous losses. The analytical model results in an equation that must be solved iteratively. Computing an iterative solution in a spread sheet gives the students valuable experience with modeling techniques commonly used in solving problems they will encounter in industry. The experimental component provides ample opportunities for students to gain experience with pre-test uncertainty estimation, formulating and executing a test plan, and with post-test statistical analysis of the measured data. The experimental apparatus is made up of inexpensive items found in home improvement stores. The apparatus is small in physical size and requires only a limited amount of water, meaning it can be used in minimally equipped instructional spaces. On account of the simple apparatus, parameters such as tubing length and the elevation of the water reservoir are easily varied. This allows students to carry out such valuable exercises as calibrating their analytical models to experimental results on a baseline configuration, and then investigating how well the calibrated model can predict the flow when the geometry is modified. The paper includes a description that will allow others to easily reproduce the apparatus, and also reflections on the utility of the exercise as an educational tool.
