1 / 11

Aerodynamics 1: Energy Conversion

Aerodynamics 1: Energy Conversion. References: NREL (Pat Moriarty, Tony Jimenez). Wind Turbine Components. Courtesy: Alternative Energy Institute. Energy and Power. Energy is the ability to do work Energy = Force * Distance Electrical energy usually measured in kWh Power = Energy / Time

kellsie
Download Presentation

Aerodynamics 1: Energy Conversion

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Aerodynamics 1: Energy Conversion References: NREL (Pat Moriarty, Tony Jimenez)

  2. Wind Turbine Components Courtesy: Alternative Energy Institute Wind Energy

  3. Wind Energy

  4. Energy and Power • Energy is the ability to do work • Energy = Force * Distance • Electrical energy usually measured in kWh • Power = Energy / Time • Electrical power usually measured in kW Wind Energy

  5. Kinetic Energy • Kinetic energy (KE) is the energy of motion • Air molecules have mass, and wind is moving air. Thus, wind has kinetic energy. • Wind turbines convert the wind’s kinetic energy into mechanical kinetic energy (spinning the rotor). • Mass = density * volume: • What is the kinetic energy of a 1m cube of air moving at 5 m/s in Colorado (r = 1 kg/m3)? Wind Energy

  6. Energy Conservation and Energy Conversion • When the turbine extracts kinetic energy from the wind, the speed of the wind is reduced. • Some of the wind’s kinetic energy is converted into mechanical kinetic energy, i.e., the rotation of the turbine rotor. • Some of the wind’s kinetic energy remains in the wind (conservation of energy). • What would happen if all of the wind’s kinetic energy were converted? Wind Energy

  7. Power • Power available in the wind • r = air density • v = wind speed • A = cross sectional area swept by rotor (“swept area”) Wind Energy

  8. Energy and Power – II • Consider the units of the kinetic energy equation:and the units of the power equation: • Recall: Power = (Energy) / (Time) and Mass = (Density)*(Volume) Wind Energy

  9. Power Coefficient • Power coefficient Cp is a measure of the aerodynamic efficiency of the wind turbine • Q = turbine’s aerodynamic torque • W = rotor rotational speed • Betz limit - theoretical maximum Wind Energy

  10. Tip-Speed Ratio • Ratio of the linear speed of the tip of the blade to the wind speed • Linear speed of a rotating object is angular speed times distance from center of rotation • l = tip-speed ratio • R = rotor radius • w = angular speed • v = wind speed • What is the tip-speed ratio of a 20 m diameter rotor rotating at 6 rad/s in 10 m/s wind? Wind Energy

  11. Cp for Various Configurations Wind Energy

More Related