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Technical data


Influence of number of rotor blades

Article no: P9515500
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Principle

From their environment, students usually know of wind turbines that have 3 blades. There are also models with only 2 blades or with completely different structures. In contrast, water wheels have more blades ("Blätter"), and they are suitable for driving large machinery. In the past they were, for example, used for grinding grain.

Wind wheels are used for the production of electrical energy. The optimal number of blades is a consequence of not only fthe maximum useful energy produced by the wind but also from the necessary material inventory and the stability of the wind wheel while in operation.

Benefits

  • Experiment is part of a complete solution set with a total of 26 experiments for Renewable Energy solar cells, wind power, water power
  • Safe experimentation: The fan in the blower is protected against touch
  • The power supply used is versatile and is particularly suitable for pupil tests for all ages

Tasks

Compare wind wheels that have different numbers of rotor blades.

For the comparison the generator of the wind wheel is equipped first with 3, and then with 6 rotor blades. The wind wheel will then be loaded with a light bulb and secondly a LED, while the output voltages of the wind wheel are measured in response to different wind speeds.


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