Wind Turbine Optimization Challenge
Estimated Time: 45-60 minutes Materials: Internet-connected device, Wind Turbine Optimization Simulation, blank paper or notebook for sketching (optional).
Part 1: Engage (Anchoring Phenomenon)
Wind energy is one of the fastest-growing sources of renewable energy in the world. Wind turbines capture the kinetic energy of the wind and convert it into electrical energy. However, not all wind turbines look the same. Some have enormous blades, some have different numbers of blades, and they are often pitched (angled) differently.
Phenomenon: How do engineers maximize the power generated by a wind turbine?
Questions to Consider:
- How do you think the speed of the wind affects the power output?
- Why do most modern wind turbines have exactly 3 blades?
- What trade-offs might engineers face when designing a turbine? (e.g., cost, material stress, efficiency)
Record your initial thoughts and questions: ___ _______
Part 2: Explore (Simulation Investigation)
In this investigation, you will use the Wind Turbine Optimization Simulation to determine the optimal configuration for a wind turbine to maximize power output and efficiency at a specific wind speed.
Constraints:
- Wind speed cannot be controlled in the real world, but you will design a turbine optimized for a typical wind speed of 12 m/s.
- You can adjust:
- Blade Length (m) (20m to 100m)
- Pitch Angle (°) (0° to 30°)
- Number of Blades (1 to 6)
Instructions:
- Open the Wind Turbine Optimization Simulation.
- Set the Wind Speed to 12 m/s.
- Conduct at least 5 trials varying the Blade Length, Pitch Angle, and Number of Blades.
- For each trial, click “Record Data” and note the Power Output (kW) and Efficiency ($C_p$).
- Use the “Export Data” feature or record your data manually in the table below.
Data Collection Table
| Trial | Wind Speed (m/s) | Blade Length (m) | Pitch Angle (°) | Number of Blades | Power Output (kW) | Efficiency ($C_p$) |
|---|---|---|---|---|---|---|
| 1 | 12.0 | |||||
| 2 | 12.0 | |||||
| 3 | 12.0 | |||||
| 4 | 12.0 | |||||
| 5 | 12.0 |
Part 3: Explain (Sensemaking)
Based on your data, answer the following questions:
-
Blade Length: How did increasing the blade length affect the power output? Did it affect efficiency in the same way? Explain your reasoning using evidence from your trials. _____
-
Pitch Angle: What was the optimal pitch angle for your turbine at 12 m/s? Why do you think pitching the blades too much or too little decreases efficiency? _____
-
Number of Blades: Did adding more blades always increase the power output? Explain why a 3-blade design might be the standard in the industry, considering potential trade-offs like weight, cost, and aerodynamic interference. _____
Part 4: Elaborate/Evaluate (Argumentation & Modeling)
The Engineering Challenge: A city is planning to install a new wind farm. They need a wind turbine design optimized for their average wind speed of 12 m/s. They have a limited budget, meaning they cannot simply use the largest possible blades or the maximum number of blades without justifying the cost.
Deliverable: Engineering Proposal Write a short proposal recommending a specific turbine configuration (Blade Length, Pitch Angle, Number of Blades). In your proposal, you must:
- State your recommended configuration and the expected Power Output and Efficiency.
- Provide an evidence-based justification using data from your simulation trials to explain why this design is optimal.
- Discuss trade-offs and constraints. Acknowledge at least one constraint (e.g., the cost of longer blades, or the weight of additional blades) and explain why your design is the best compromise.
- Identify remaining problems. Describe any parts of this real-world problem that remain unsolved even if your design is implemented (e.g., what happens when the wind speed drops below or exceeds 12 m/s?).
Extension Options:
- Variable Wind: Test your optimal design at wind speeds of 5 m/s and 20 m/s. Does the optimal configuration change? Why or why not?
- Economic Modeling: Assign a hypothetical cost per meter of blade and calculate the “kW per dollar” ratio for your design to further justify your proposal.
Teacher Notes
NGSS Alignment:
- Performance Expectation: HS-ETS1-3: Evaluate a solution to a complex real-world problem based on prioritized criteria and trade-offs that account for a range of constraints, including cost, safety, reliability, and aesthetics as well as possible social, cultural, and environmental impacts.
- SEP: Constructing Explanations and Designing Solutions
- DCI: ETS1.B: Developing Possible Solutions
- CCC: Influence of Science, Engineering, and Technology on Society and the Natural World
Evidence Statements Addressed:
- 1.a.i. Generate a list of realistic criteria and constraints: Students operate within the constraints of wind speed and consider the trade-offs of blade length/number (cost/weight).
- 1.a.iii. Analyze strengths and weaknesses: Students analyze how different variables affect power output and efficiency using simulation data.
- 1.a.v. Provide an evidence-based decision: Students recommend an optimal design based on their data, balancing performance with theoretical constraints.
- 2.a. Describe remaining problems: Students identify issues such as variable wind speeds that are not solved by a single optimal design.