2 024/25 Purdue University Science Olympiad Invitational Competitor Names: ______________________________ Team Name and Number: _________________________ ● You are allowed one 3-ring binder as well as two calculators of any type. Papers may be removed from the binder, but be sure to clean up your area after you finish the test. ● Please round all final calculated answers to 2 (two) decimal places, andinclude units. ● Circle or box all answers. ● Both partners must present themselves for the blade testing portion. ● (Post-tournament) Contactmmereu@purdue.eduwith anyquestions regarding this event. ● Good luck! Exam Score: /100 B 1 . Vocabulary: (1 point each) Use the answer bank below to complete the vocabulary section. Terms (each is used once): Anemometer Cut-In Speed Drag Feathering Inverter Lift Nacelle Transformer Turbulence Wind Shear I. The change in wind speed and direction at different altitudes or over short distances. II. I rregular, chaotic air movement caused by obstacles like hills or buildings, which can reduce the efficiency of wind turbines. III. he housing on top of a wind turbine tower that contains the gearbox, generator, and T other critical components. IV. The minimum wind speed at which a wind turbine begins generating electricity. V. n aerodynamic force that opposes the motion of an object through air, reducing the A efficiency of turbine blades. VI. n aerodynamic force that moves perpendicular to the direction of airflow, helping A turbine blades spin efficiently. VII. device used in power transmission to increase or decrease the voltage of electricity for A efficient long-distance transmission. VIII. device that converts direct current (DC) electricity generated by wind turbines into A alternating current (AC) for use on the power grid. IX. he process of adjusting the angle of wind turbine blades to reduce rotation and minimize T damage during high winds. X. A device used to measure wind speed and sometimes wind direction. 1 2. Identify the following parts of a wind turbine using the answer bank below: A: ______________________________ B: ______________________________ C: ______________________________ D: ______________________________ E: ______________________________ F: ______________________________ G: ______________________________ H: ______________________________ (1 point each) Drive Shaft Gearbox Generator High Speed Shaft Hub Rotating Bearing Rotor Blades Tower Support 3 . Sort the following countries in order of most wind energy generation to least wind energy generation, as of 2022. (Information from the U.S. Energy Information Administration). (5 points) China Brazil Germany United Kingdom United States 1 . 2. 3. 4. 5. 2 Multiple Choice(12 ptstotal) 4. Which one of these locations is the ideal spot for a wind farm in terms of efficiency? (1 point) a. On the side of a mountain b. In a corn farm c. On the ocean d. On the side of a highway 5. What is Betz’s Law? (1 point) a. The maximum efficiency a turbine has in converting energy from wind b. The amount of renewable energy a turbine can produce c. No turbines can be built above 2000 meters sea level d. By 2030, 20% of wind turbines will be recyclable 6. What materials are wind turbine blades MAINLY constructed of? (1 point) a. Fiberglass b. Iron c. Metal-3I d. Sigilyph 7. What is the primary function of a generator in a wind turbine? (1 point) a. Increase wind speed b. Convert electrical energy into mechanical energy c. Convert mechanical energy into electrical energy d. Convert wind energy into mechanical energy 8.What are the two main types of turbines (selectall that apply)? (1 point) a. VAWT b. HAWT c. Up-turned d. Down-turned 9. What type of generator is typically used in modern wind turbines? (1 point) a. Synchronous Generator b. Induction Generator c. Step-Up Generator d. Step-Down Generator 3 1 0. What geographical and environmental factors are considered when siting a commercial wind farm? (1 point) a. Wind speed b. Land availability c. Proximity to local land structures d. All of the above 11. Which of the following is the most efficient type of power storage? (1 point) a. Lithium ion batteries b. Metal Oxide batteries c. Hydrogen Storage d. Pumped Hydro Storage 12. How could installing a wind turbine be negative to the area around it? (1 point) a. The energy it provides b. The sound it emits c. It emitting CO2 d. The amount of space it takes up in the ground 13. What material is typically used for power lines to minimize losses? (1 point) a. Iron b. Gold c. Copper d. Diamond 1 4. Which of the following is an advantage of using high-voltage direct current (HVDC) systems in wind power transmission? (1 point) a. Transmitting power over low distances b. Storing power in a short circuit c. Transmitting power over long distances d. Storing power in a long circuit 15. How does zoning affect the installation of individual wind turbines? (1 point) a. The noise limit of a turbine b. Can only be installed during daylight hours c. Wind turbines have to have a anixemeter to pick up wind speeds d. Has to be installed 10 feet below the ground for stability 4 Short-answer Free Response(18 ptstotal) 16. How do flywheels contribute to energy storage in wind power systems? (3 points) 1 7. According to the U.S. Energy Information Administration, the first recorded use of wind energy was in 5,000 BC for what application and by who? (3 point) 1 8. In which state was the world’s first wind turbine farm installed, and when? (3 points) Bonus: How many turbines were installed? (+1) 1 9. The United States electrical Grid delivers AC at what frequency? What does this mean? (3 points) 2 0. Name three examples how wind turbines impact bird and bat populations, and what steps are being taken to mitigate these effects? (3 points) 21. Describe how a wind turbine produces energy. (3 points) 5 Calculation Questions(20 ptstotal) 2 2. A wind turbine has a rated power of 4 MW. Over a year, it generates 4,500,000 kWh of energy. What is the turbine’s capacity factor? (5 points) 2 3. A wind turbine has a tip speed of 20 m/s and the wind has a speed of 10 m/s. What is the tip speed ratio? (5 points) 2 4. If a 600V wind turbine sends power over a transmission and the output home has a power consumption of 30kW and a voltage of 120V. If the resistance of the transmission line is 10 kohms, what is the power of the wind turbine? Use 250 as the turn ratio between the house and the transmission line. (5 points) 2 5. If the output voltage of a wind turbine is 690V and the grid power supply is at 200kV. What is the turn ratio? (5 points) 6 2 6.Big Problem! (27 ptstotal) Purdue has assigned you to develop a wind farm. You and your partner have collected wind velocities at the site. Wind Velocities (m/s) Cubed Wind Velocities (m/s)3 5.9 6.1 7.7 8.2 9.5 After researching and having discovered the Weibull distribution, it has the following form: here f(V) represents the probability that a certain wind speed (V) has occurred. C represents W the scale parameter (m/s) and K represents the shape factor. or some context, the shape factor describes the breadth of the wind speed distribution. Large F shape factor values have a narrow wind speed distribution. Small Shape factor values have a broad wind speed distribution. The scale parameter describes how windy a location is. here are multiple ways to estimate the shape and scale factor. Moment, cumulative probability, T maximum likelihood, and Power density are common methods. For this scenario, you choose the Power density method. The power density method calculates the shape parameter from the Following Equation: Ep is the energy pattern, which can be calculated by the following: here the numerator is the mean of the cubed wind velocities. The denominator is the cube of W the mean wind velocities. 7 Determine the shape factor K: a. Average Wind Velocity: (2 pts) b. The cube of the Average Wind Velocity: (2 pts) c. Average of the cubed Wind Velocity: (2 pts) d. (2 pts) K= The scale factor is given by the following equation: Where Γ(x) is the gamma function. Here are some values of the gamma function: x Γ(x) 0.5 1.772 0.75 1.225 1 1 1.25 0.906 1.5 0.886 1.75 0.919 2 1 2.25 1.133 2.5 1.329 8 Determine the scale factor C: (2 pts) e. C= Now that you have determined the K factor and C factor. You decide to calculate the Mean wind 𝑃 power density (𝐴 ) using the following equation: A is area, ⍴ is the density of air (use 1.225 kg/m3).Determine the Mean Wind Power Density: f. Mean wind power density: (2 pts) Notice that what you have calculated is the value of the power density (Pd). 9 ay! You have determined the mean wind power. You are stuck between three different wind Y turbines. Given Purdue gives you a plot of land, width 600m (row) by length 1200m (column), find the turbine that maximizes the power generation. Create a square grid of wind turbines. Wind turbines on the same row should be apart by 3 times the length of the rotor diameter. Wind turbines on the same column should be 7 times the length of the rotor diameter. Assume you can place wind turbines on the perimeter of the given land. Turbine Rotor Diameter (m) Efficiency Holloway 85 39% Mackey 72 42% Ross-Ade 59 33% g: Fill out the following Table: (12 pts) Holloway Mackey Ross-Ade Mean Wind Power 2 𝐷 2 ( ) ·π 𝑃𝑑· 1000 Mean turbine Power (Hint: use efficiency here) umber of Turbines N that can Fit (round to the nearest whole number) otal Mean Power T Generated h. Wind Turbine that you select: (3 pts) 10 iebreakers T 27. According to the Indiana Office of Energy and Development, how many operating wind turbines are there in the state of Indiana? 2 8. Free response: write as much or as little as you’d like. What factor(s) poses the greatest challenge to the widespread adoption of wind power as a reliable energy source in the U.S.? 11
