Answers to Windmill Project Research Questions

1. What is a windmill?

Windmills use blades to harness wind’s kinetic energy. A windmill is designed to do work, like grinding grain.

For this project you can also use the wind turbine. A wind turbine is like a windmill, but instead of doing work, it generates electricity.

2. What are the parts of a windmill?

There are many parts of a windmill or turbine. Theses parts include the rotor, wind vane, blades, brake, low-speed and high-speed shaft, tower, yaw drive, yaw motor, gear box, generator, controller, anemometer, and nacelle.

3. How many blades do windmills usually have?

Windmills normally have 2-4 blades. Wind turbines, used for electricity, usually are taller and have 3 blades.

4. What are common shapes of windmill blades?

Most of today’s windmill blades are airfoil type blades or wing-shaped blades. These type of blades are like the wings on an airplane, where one side is flat and the other side is more rounded.

5. What are some materials used to make windmill blades?

Some common materials used to make windmill blades are steel, aluminum, fiberglass, glass with reinforced plastic, wood epoxy, and carbon filament with reinforced plastic.

6. How does a windmill work?

When wind hits the blades of a windmill it causes lift which makes the blades rotate. The blades then rotate a shaft connected to a generator which then produces electricity.

7. What are the forces that act on a windmill’s blades?

There are 2 forces that act on a windmill’s blades. The first one is the lift force, this force actually occurs on the backside of the blades causing a pocket of air pressure. The next force is called the drag force. This force is the wind hitting the front side of the blade. The 2 forces together cause the blades to rotate.

8. What is a windmill used for in the united states and/or in other countries?

Windmills or turbines are used all over the world for power or electricity. Small farmers use them to pump water or crush grains. Bigger companies use them to power small towns or an entire school.

9. Where are windmills normally located?

Windmill’s are normally located in hilly, open, and high wind areas. Some examples would be California, Texas, and the open ocean.

10. What energy transformations occur with a windmill? Explain this transformation.

When the wind blows a windmill, the windmills blades are designed to catch the wind which is actually kinetic energy because it is moving. When the blades catch this kinetic energy, they spin a shaft that connects to a generator which turns that kinetic energy into mechanical energy.

11. What is power and ho do you calculate it? What are the units of power?

Power is the rate at which work is done. You can calculate power by the formula

P= W/T, where p is power, w is work and t is time.

The units of power is the Watt.

12. What is work and how can it be calculated? What are the units for work?

Work happens when a force applied to an object moves that object.

You can calculate work by multiplying the force by the amount of movement or W= f*d.

The units for work are joules, which are the same units for energy.

Tip speed ratio:

TSR= tip speed of blade/ wind speed1st you have to measure how long it takes

the blades to make 1 full revolution. (count how many time the blades rotate in 1 minute and divide by 60.)

2nd you have to find the tip speed. Which is V=2(pie)r/time.

Now transfer the data into the TSR formula and calculate.