Throughout the world, water turbines have been used in the generation of power. This happens when water that is under pressure strikes the turbine vane thus producing mechanical work. The force that is generated gives out rotational motion when the jet hits the vanes. A clear example of a water turbine is the Pelton wheel. This form of a turbine has more than one water jets which are normally tangentially directed towards vanes which are tightened on the turbine disc rim. The water creates an impact on the vanes producing a torque on the wheel. The torque makes the wheel to rotate thus developing power. The prediction of the pelton wheel’s output and determination of the optimum speed of rotation requires the understanding of the jet’s deflection to produce a force at the bucket and its relation to the momentum rate of the jet. This experiment explores the various forces that are exerted by a water jet on different plates. In this experiment, the measurement of the generated force when a water jet strikes a deflector was obtained.
Whenever a horizontal water jet with a velocity v1 hits a freely moving plate, a force would be generated to the plate through the jet’s impact. This force, according to the theory of momentum is equal to the needed force in bringing back the plate in the initial position. This force should be same as the rate of momentum change of the flowing water towards that direction. In this regard, when F is a force of balancing needed to return the plate to the original position, it means that;
F = ρ Ǫ (v1-v2), where V2 includes the velocity of the jet in the direction that is horizontal after hitting the plate, V2 is certainly zero. This implies that
F = ρ Ǫ v1 ...Show more