Pelton Wheel Turbine, Numerical Study, Industrial

Description

Pelton Wheel Turbine, Numerical Study, Industrial Application

Abstract Pelton wheel turbine

This article is about a popular impact turbine. The Pelton turbine is the only impact hydraulic turbine currently in use. According to Newton’s second law, this turbine uses a fluid jet to generate energy. This turbine is hit by a pressurized water nozzle tangentially to the bucket connected to the runner and rotates the runner.

The buckets are pairs so that in addition to the balance of force that is applied, the momentum is transferred smoothly and efficiently. The pellets are in different sizes. Large sizes are used in dams because these turbines are specifically designed for large heads, and small sizes are used to generate electricity in remote areas.

Purpose Pelton wheel turbine

In this project, a small Pelton turbine with a diameter of 300 mm and 15 buckets is simulated in ANSYS Fluent software. Also, this project aims to get the amount of torque produced in this turbine.

Pelton wheel turbine Introduction

Lester Allen Pelton, an American inventor, traveled to the American West in 1860 at the age of 30 in search of treasure and worked in a mine in northern California. At that time, most works were done with the help of steam engine power. But these engines consumed large amounts of wood as fuel.

The water cycles used in large rivers with very low efficiencies were useless in small rivers near the mine. Hence, Pelton began to design a wheel that could operate at low water flow rates.

In the mid-1870s, he built his first laboratory turbine from wood, and the first sample of real iron was installed in 1878 in a mine near Nevada. The Pelton wheel’s positive advantages and high efficiency made his invention soon reach mass production.

Pelton’s initiative was to design a separator to divide the input jet into two equal streams. The same idea increased the water cycle efficiency from about 35% to 90%. There are several types of impact turbines. But the model that Pelton invented is still the most efficient.

Pelton wheel turbine

The rotor of this turbine consists of a disk with several blades installed around it. These blades are also called plates. One or more nozzles are positioned so that the jet of water coming out of each nozzle can be thrown directly and tangentially to the disk toward the center of each plate.

A separator or splitter divides the input jet into each plate into two equal streams. These two equal streams leave the plate after passing through a curved path on the inner surface of the plate in the opposite direction to the direction of the inlet jet.

Simulation

The geometry of the simulation is drawn in ANSYS SpaceClaim software. The mesh of the present model was created by ANSYS Meshing software, which produced about 10,000,000 triangular cells. In addition, to reduce the computational cost in Fluent software, triangular meshes were converted to Polyhedral (2923341 Polyhedral meshes).

Pelton simulations are performed steady with the k-ε model is Realizable as the turbulence model; we also used the VOF model for the two-phase equation. The fluid used in this simulation is air and water for the continuous phase. Pelton rotation is performed using the mesh motion command(3000 red/s). Coupling of velocity and pressure equations is also performed using the Coupled algorithm.

 Pelton wheel turbine result

This project aims to obtain the produced momentum of this Pelton and the produced lateral force to select the appropriate axis.

Looking at the chart above, we conclude that after 0.078 seconds, Pelton’s momentum reaches a constant oscillation.

Direction	Force
x	-0.37569732
y	-1.4908452
Z	31.86981