Introduction and Purpose
Water falling from a height (or under pressure) has been used since time immemorial to generate power or do work. Energy generated from water has been used to grind grain, plow fields, turn transmissions, and countless other mechanical tasks. With the invention of electromagnetic motors and generators, more recent applications of water energy have been hydroelectric. That is, hydroelectric energy production is the conversion of the fluid mechanical energy of running (or falling) water directly to electromagnetic energy.
In this project your team will construct a waterworks project - you will build a small-scale hydroelectric power generator. This project will once again integrate the physics and calculus that you are currently learning with engineering modeling and design components.
The goal of this project is to design and construct a hydro-generator that can power a light, using as a water source, a tap in a laboratory sink in the Physics building. The generator must also be equipped with special protection features:
- If the water flow is too low - an alarm must sound
- If the water flow is too high - a different alarm must sound
The intention of the low and high water flow alarms is to mimic protection features that would routinely be added to any power generation system. If the water flow were too high, for example, damage may be caused to a rotating shaft or bearings on a generator.
The hydroelectric generator
There are many strategies you can use to construct a water-powered light-generation system. Your team may build this system using:
- Frames and moving parts from the Erector Sets
- You may also use other materials (plastic, wood, etc.) to construct the frame, other stationary parts, or moving parts
- Constructed or purchased electric motors
- Electrical sensors, alarms, and amplifiers with the breadboard/electroncs kits
- You may also use other electronic components, purchased from Radio Shack or a similar electronics company
- The total cost cannot exceed $20!
You should spend some time pondering this project carefully before building anything. Use your best problem-definition and brainstorming skills to consider:
- What strategies can be used to convert energy of running water to electricity?
- Is electrical generation necessary? Are there other approaches?
- What materials can be employed? What are best suited for this project?
- How can low flow and high flow be monitored?
We will show you the lab and the water source during class hours - but you will have access to this room during normal school hours for the next two weeks. The flow from the tap will be divided arbitrarily into three regions:
- Less than 25% of maximum flow - Low Flow Regime
- Greater than 75% of maximum flow - High Flow Regime
- Between 25% and 75% of maximum flow - Safe Operating Region
Again, the project should be built with safety in mind (i.e., no hazardous operating conditions), designed for robust operation (i.e., it should be able to work at least during the demonstration period), and with as much creativity as you can muster.
You have approximately two weeks to design and construct the generator. At 8:00AM on thursday, 05/04/00, your team must report to the FC classroom (ECG224) with the generator. The examination will begin at 8:30AM, so you will have thirty minutes to assemble or prepare your model for the final. Your team will have to give a 6 minute presentation to the examiners (and the rest of the class) to discuss the operation, design process, model performance, and so on.
We will then go over to the Physics Lab, where you can demonstrate the performance of the system. As in last semester, you will also be called upon to evaluate the design and performance of another team's generator. Since your team has gone through the process of designing, constructing, analyzing, modeling, testing, evaluating, modifying, and describing your system, you have learned a great deal about this type of project. Therefore, you are well poised to assess the quality of hydroelectric systems, so during the competition, we would like you to carry out an evaluation of another team's roller coaster. The team you evaluate will be revealed on the day of the competition. To carry out this evaluation, we would like you to use a KT decision analysis procedure. You choose the "musts" and "wants" categories for the analysis. To make this process go smoothly, make up the KT table in advance of the competition. You must interview the team to decide whether the team can describe what it has done and whether it can describe why it has done some activity.
Your team must also submit a final report on the day of the competition. You should have written all of this except the Appendix (containing the evaluation of another team's system) prior to the day of the demonstration. In brief, the report should be in the same format as for previous projects. The following sections should be included - and each section title should be highlighted:
- Purpose of project
- Design Process
- Preliminary Designs (use sketches or CAD drawings here)
- Modeling (if carried out)
- Discussion and Analysis
Just as before, the report should be descriptive and must use proper grammar, spelling, sentence structure, and so on. It should also be illustrative and use graphs, sketches, figures, and so on as necessary. You want the report to be clear and concise, so that you could pick it up ten years from now and be able to understand what your team has done.
On the day of the demonstration
You will have the following five tasks:
- Observe the performance of the other team's generator.
- Carry out the interview with the other team.
- Perform the KT analysis on the other team's generator.
- Write an evaluation of the other team's system based on a KT analysis and attach this as an Appendix to your own report.
- Submit the report in hard-copy (including the Appendix) and on disk (excluding the Appendix)
- Evaluate your own and your teammates' performance in this last project, using the $100 distribution form, which you have used in the previous projects.