Matura Thesis 2017

As part of my Matura thesis at the Cantonal Middle School of Uri, I built a model of a Pelton turbine and investigated the influence of the blade shape on the performance of a Pelton turbine.

Abstract

In hydroelectric power generation, the kinetic energy of the water is used to drive a generator with the help of a turbine wheel. The efficiency of the turbine depends on the type of turbine wheel. The Pelton turbine is a frequently used type of turbine, which is equipped with specially shaped blades. This special shape allows high efficiencies to be achieved. Within the scope of this work, a model with three different turbine wheels was built in order to find out in experiments what influence the blade shape has on the performance. For this purpose, various test series were carried out. From these data, the maximum power and the efficiency were calculated. These values were then compared with each other, interpreted and compared with the theory.

Scope

  • Build a model
  • Perform measurements
  • Evaluate measurements

Awards & Mentions

  • Rating with the best mark 6

Project Outcome

Comparison of the different blade shapes

It could be shown that significantly more power can be measured with the Pelton turbine than with a flat or C-shaped profile.

The cause of the performance maximum

Furthermore, it was observed that the optimum performance is at a specific rotational speed. Due to the law of momentum transfer, the turbine delivers the maximum power when the complete kinetic energy is taken from the water. This is the case when the blade moves at half the speed of the water jet. This behaviour was confirmed by measurements on the model.