Project Based Teaching: A Case Study From A Hydraulics Class

Hydraulics is currently taught as one-half of a 3-credit course in the Environmental Engineering Program at the Mercer University School of Engineering. The topics covered include fluid properties, fluid pressure, forces on submerged surfaces, fluid flow in pipes, pipelines, pipe networks, and pump design and selection. The first semester this course was taught the material was presented topic by topic. This created a very choppy course structure and the impression that hydraulics was a collection of individual topics, many of which had little relevance to each other. A project-based teaching format was adopted to create a more cohesive course structure, help the course move more fluidly from topic to topic, and demonstrate to the students the application of the material they were learning. The project required the students to design a dam to create a reservoir in a theoretical gorge, pipe and pumps to convey water from the reservoir to a downstream community, and a pipe network to distribute the water within the community. This project was distributed to students on the first day of class and was used to drive the sequence of the course lectures. In addition to keeping the students focused on why they were learning a topic, the project based teaching format also produced a just in time teaching format. This paper will present the project used to teach the hydraulics class, a qualitative analysis of how the use of project-based teaching affected this class, and modifications planned for the next offering of the course. Suggestions for the design of projects will also be presented. 1.0 Introduction Hydraulics is currently taught as one-half of a 3-credit course in the Environmental Engineering Program at the Mercer University School of Engineering. The topics covered include fluid properties, fluid pressure, forces on submerged surfaces, fluid flow in pipes, pipelines, pipe networks, and pump design and selection. The first semester this course was taught the material was presented topic by topic. This created a very choppy course structure and created the impression that hydraulics was a collection of individual topics, many of which had little P ge 613.1 Proceedings of the American Society for Engineering Education Annual Conference & Exposition Copyright 2001, American Society for Engineering Education relevance to each other. It was obvious that the students did not see how the course topics fit together as a whole. Literature on project-based teaching (Felder, et al., 2000; Mahendran, 1995) suggested that this approach could be used to create a more cohesive course structure, help the course move more fluidly from topic to topic, and demonstrate to the students the application of the material they were learning. The use of a project to drive instruction also seemed to be a promising a method to approach an active learning format where the instructor is more of a facilitator than a lecturer. The challenge was to develop a project that was realistic, incorporated all of the course topics, and contained the appropriate level of complexity. The final project required the students to design a dam to create a reservoir in a theoretical gorge, pipe and pumps to convey water from the reservoir to a downstream community, and design a pipe network to distribute the water in the community. This project was distributed to students on the first day of class and was used to drive the sequence of the course lectures. Thus, project based teaching not only kept the students focused on why they were learning a topic but, it also produced a just in time teaching format. Material was presented only as it was needed to work on the project. This paper presents the project used to teach the hydraulics class, a qualitative analysis of how the use of project-based teaching affected this class, and modifications planned for the next offering of the course. Suggestions for the design of projects will also be presented. 2.0 Project Details The project used in a project-driven course may or may not be used to cover all of the course material. The project used to cover the hydraulics section of this course did provide coverage of all of the required topics, Table 1. Table 1. Correlation between project topic and hydraulics material covered. Project Topic Hydraulics Material Covered Reservoir Analysis Mass balance Dam Design Water properties, fluid pressure, pressure on submerged surfaces, and statics Pipe Design Water properties, pipe flow theory, pipe design, and pipeline design Pipe Network Design Fluid flow theory, flow between connected reservoirs, and pipe network design Pump Design Pump theory, single pumps, multiple pumps, selection of single pumps, and design and selection of pumps in parallel and series. The following section presents the project as it was distributed to the students 2.1 Introductory Statement Your task as an engineer is to provide a water supply for a planned community. Your project will involve (as a minimum): P ge 613.2 Proceedings of the American Society for Engineering Education Annual Conference & Exposition Copyright 2001, American Society for Engineering Education • Sizing a reservoir to provide a water supply, • Designing a pipe and pump system to convey the water to downstream communities, and • Designing and evaluating the pipe network used to distribute water at two facilities downstream from the reservoir. The community and reservoir will be constructed in the Mercer Gorge. The Mercer Gorge has the cross-section shown in Figure 1. The reservoir and community will be located in a 10 mile straight section of the Gorge. The gorge has an average down gradient slope of 10 ft per mile (0.001894 ft/ft), see Figures 2 and 3. The Mercer River runs through the gorge with an average annual flow rate of ~800 cfs and an average annual depth of ~4 ft. Weekly river flow rates and anticipated community demands are presented in Figure 4. 0 20 40 60 80 100 120 0 100 200 300 400 500 600 700 Horizontal Position, ft E le va ti on , f t X Y (ft) (ft) 0 87 150 55 210 25 250 10 265 2 295 2 310 10 390 20 490 40 690 100 Facility A Facility B Figure 1. Mercer Gorge cross-section. 2.2 Reservoir Analysis and Dam Design In the design of the reservoir, a stable gravity dam cross-section must be designed and the weekly variations of the water depth in the reservoir must be determined.