DESCRIPTION

Technical Description

The conversion of pressure energy into kinetic energy in the rotor is characteristic for reaction turbines.

The experimental unit is placed upon the base unit HM 290. The two units together provide the basic experiments to get to know the operating behaviour and the most important characteristic variables of reaction turbines.

The water jet discharged from the rotor which drives the turbine according to the reaction principle can be observed during operation. This facilitates the understanding of the principle of operation and the underlying laws (eg. momentum).

HM 288 consists of a rotor mounted in a transparent housing and a loading device outside of the housing. The eddy current brake generates a defined load. The eddy current brake is specially developed by GUNT. It is wear-free and can be finely adusted.

The torque delivered by the turbine is determined via an electronic force sensor. The speed is measured with an optical speed sensor. The measuring values are transferred to the base unit HM 290.

The water supply and the flow rate measurement are realised with the base unit HM 290. A pressure control included in HM 290 enables the recording of characteristics at a constant head.

All the advantages of software-supported experiments and evaluation are offered by the GUNT software in HM 290.

The well-structured instructional material sets out the fundamentals and provides a step-by-step guide through the experiments.

Learning Objectives / Experiments

- principle of operation of a reaction turbine
- characteristic curves at constant head
  * relationship between torque and speed
  * efficiency dependent on speed
  * flow rate dependent on speed
  * hydraulic power and mechanical power depending on speed
- evaluation of measuring values and characteristics based on the theory