TUNNEL TESTING

We will have multiple wind tunnels at the National KidWind Challenge. All tunnels draw wind through the tunnel creating a much cleaner and more stable airflow. The size of the wind tunnel testing space is 48” x 48” x 48”. But please remember that the walls move in a bit when the fans are running.

You will need to receive turbine performance scores from each of the of tunnels:

• Tunnel 1: Low Speed (3-3.5 m/s) - 10 points
• Tunnel 2: Medium Speed (4-4.5 m/s) - 10 points + 5 points for Efficiency (ELEMENTARY + MS and HS for efficiency score only)
• Tunnel 3: Medium Speed (4-4.5 m/s) with Yaw Test - 10 points (MIDDLE SCHOOL AND HIGH SCHOOL ONLY)
• Tunnel 4: High Speed (at least 6 m/s) - 10 points

During tunnel testing, teams must run their turbines through each tunnel. Each team will receive a set number of tokens at check-in that they must trade-in to test their turbine in the wind tunnel. Each tunnel will use a different color token and one tunnel run will require one token. You can assume that you will receive 2-3 tokens per tunnel, meaning 2-3 active runs per tunnel. Once the number of teams attending Nationals has been confirmed, we will finalize the number of tokens to be distributed. Each turbine will be placed in each tunnel for 30 seconds in order to calculate the energy and power produced.

Wind Tunnel Testing Protocol:

• Hand the judges 1 token (be sure it is the correct token for that tunnel).
• Place your turbine in the tunnel and connect the wires to the data logging hardware.
• The judges will turn on the fans and let the tunnel and turbine get up to speed.
• The judges will ask if you want to run a trial. You can say YES or NO.
• If you say NO (you do not want to run a trial): Remove the turbine, collect back your token, make any adjustments and go to the back of the line.
• If you say YES: The 30 second trial begins. The only way that a test can be redone is if judges determine that there has been a turbine failure and your turbine no longer functions.

Tunnel Details:

Tunnel 1: Low Speed Wind Tunnel
This tunnel will have wind speeds of 3-3.5 m/s.  This will be a 30 second trial.

Tunnel 2: Medium Speed Wind Tunnel (ES only + MS/HS for Efficiency)
This tunnel will have wind speeds of 4-4.5 m/s.  This will be a 30 second trial.  We will also test the efficiency of your wind turbine in this wind tunnel. Efficiency is calculated by measuring your rotor diameter and wind speed in the wind tunnel. With these two variables, in addition to your average power output, we can calculate how efficiently your turbine converts wind energy into electrical energy.

Tunnel 3: Medium Speed Wind Tunnel with a Yawing Test (MS/HS only)
This tunnel will have wind speeds of 4-4.5 m/s. This will be a 30 second test. In this tunnel your wind turbine will be placed on a Lazy-Susan that can rotate. Ten seconds into the test we will rotate the Lazy Susan AT LEAST 90 degrees and lock the table in place, so that the turbine is turned out of the wind. Be sure to consider how you might modify your design to best perform during this Yaw Test. For more details on our Yawing Tunnel, see this guide.

Tunnel 4: High Speed Wind Tunnel with Efficiency
This wind tunnel will have wind speeds of at least 6 m/s. This will be a 30 second trial.

Note: Teams will be able to test and practice in the tunnels before competition begins on Sunday, May 14th from 4-6pm.

Each wind team will be scheduled for a 15-minute wind turbine judging session with a panel of judges. During this session, the team will have up to 10 minutes to present their turbine design to the judges. The judges will have the remaining time to discuss the project, ask questions, and evaluate the students' knowledge.

Each solar team will be scheduled for a 30-minute solar structure/device judging session with a panel of judges. During this session, the team will have up to 10 minutes to present their design to the judges. The judges will have up to 10 minutes to assess the performance of the structure/device under a solar array. The judges will have the remaining time to discuss the project, ask questions, and evaluate the students' knowledge.

We encourage all teams to prepare a formal presentation and share supplementary materials which may include photos, data tables, notebooks, and/or project iterations.

What to bring to your judging session:

• Your physical turbine or solar structure/device. Be sure to save any turbine-busting tunnel time until after your judging session.
• A formal presentation prepared for the judges. This may include a poster board, physical items for the judges to view like design iterations and data logs, or digital slides that detail your process.
• If you are preparing a digital presentation, you must also bring a way for the judges to view it. We will not have projectors available. We suggest bringing a tablet, with your presentation queued up, that can be placed in front of the judges so that they can view your presentation. Reach out to Meghan at Meghan@KidWind.org

In this Instant Challenge, teams across all divisions will be asked to work with solar panels and water pumps to do some solar water pumping. Teams will have 30 minutes for this challenge and all the materials will be provided in the testing room.

For more information about solar water pumping, check-out these resources:

• Coming soon!

As a part of this challenge your team will need to develop a creative way to help persuade your community to support a proposed renewable energy project. Teams will be given the exact scenario/prompt at check-in!

Elementary School teams will be asked to produce a poster to help convince your community to support the project outlined in the prompt.

High School and Middle School teams will have a bit more flexibility in their deliverable and will be able to produce a poster, other printed materials, op-eds, social media posts, a short video, jingle or ad, or any other interesting and engaging method to communicate your message!

All submissions must be turned in or uploaded by 6pm on Tuesday, May 16th.

In this challenge, High School teams will use a Kill-A-Watt meter and energy flow charts to explore and answer questions about energy efficiency and how we produce and use energy in the United States.

See this guide for help preparing for the challenge!

The third instant challenge for elementary and middle school divisions will be a surprise!

Each team will be scheduled for 30 minutes for these challenges. No preparation required - you'll get everything you need, including the directions, in the room.

Teams will participate in a Quizbowl to evaluate their general understanding of renewable energy. Here are some of the questions you might encounter.

Offshore wind energy is becoming a booming industry in the United States. In the next 10 years the goal is to build 30 GW of offshore wind energy in the waters around the US. Most of these turbines will have a foundation in the ocean floor. The term for this is a fixed bottom offshore wind turbine.

Your job in this challenge is to design and build a fixed bottom foundation in our fake ocean and test this foundation in a wind tunnel.

This challenge event will be optional for teams that are up for the challenge. Special awards and cash prizes will be awarded to the top performers in this new pilot event.

See this guide for all the details on designing, building, and the testing your Fixed Bottom Offshore Wind Turbine.

Generator Divisions: KidWind, Open & Homebuilt

• If you have a SINGLE KidWind Generator, you will be placed in the KidWind Division.
• If you have any other non-KidWind, commercially produced generator you will be placed in the Open Division. You will also be in the Open Division is you have multiple KidWind generators.
• If you have a homemade generator, you will be placed in the Homebuilt Division.

You will be asked to declare your generator division when you submit your Team Profile form. Once you have declared your generator division you will not be able to change.

Multiple Rotors & Generator
This year, teams will be allowed to have multiple generators  and rotors in one turbine placed into the tunnel. All of these rotors would still have to fit into the standard wind tunnel. Keep in mind that if you have multiple KidWind generators, you will be placed in the Open Division. 

Power Conditioning
You must make sure that whatever generator and configuration you use provides DC power to our data loggers below 30V and 1A. If you go over for even 1 ms it can disrupt the software and we will be unable to get a reading. Maximum Power Point tracking, buck boost and other similar devices are not allowed as a part of power conditioning. Send any questions to Mike by email.

Blade Rule Clarification
The spirit of the wind challenges at the national event is to construct ONE wind turbine that can handle different wind conditions. We also understand that teams may have never tested in high speed or yawing tunnels, have blades that fail during testing, or just want to test different types of blades in the tunnel. With all this in mind, at Nationals teams may change pitch and style of blades they use in wind tunnels. They may also replace broken blades. They will not be able to change the numbers of blades they use in each tunnel.

Shroud Rule Reminder
Please make sure that your team carefully reads and understands the shroud rule. Any turbine systems with shrouds must make sure that the shroud is connected to your tower, nacelle, or other part of your turbine and that it moves with the turbine. The shroud must also fit ENTIRELY into the wind tunnel to be legal. If you have questions, send Mike a photo.