Warm Up: Name the parts of a wind turbine

Gear ratios

OBJECTIVES Students should know: Students should be able to: The major components of a wind turbine. The two dominant types of wind turbines are VAWT and HAWT.   Students should be able to: Analyze simple and complex gear trains to find the overall gear ratio. Discuss the trade-off between speed and torque in gear trains

What is a gear? A gear is a wheel with teeth that mesh together with other gears. Gears change the… Speed Torque (rot. force) Direction …of rotating axles.

Calculating Gear Ratios and Torque Always divide the driven gear by the drive gear 2 divided by 1 = 2:1 ratio This ratio is used to calculate the output torque 25 ft-lb x 2= 50 ft-lb

Divide the driven by the drive gear What is the gear ratio? 44 divided by 11= 4:1

Calculate Output Rpm & Torque Divide the input rpm by the gear ratio 1000 rpm divided by 2= 500 rpm Multiply the input torque by the gear ratio 10 ft-lb multiplied by 2= 20 ft-lb

Calculating Transmission Gear Ratios (multiple gear sets) 1. Calculate the ratio of the first set of gears by dividing the driven (output) gear by the drive (input) gear 2. Do the same for the second set of gears 3. Multiply the answer from the first calculation with the answer from the second calculation

Two or more sets of gears in mesh- calculate the first set, then the second and multiply together for final ratio 3.63 x 3.52=12.78:1

OBJECTIVES Students should know: Students should be able to: The major components of a wind turbine. The two dominant types of wind turbines are VAWT and HAWT.   Students should be able to: Analyze simple and complex gear trains to find the overall gear ratio. Discuss the trade-off between speed and torque in gear trains