What is disc turbine?
The Rushton disc turbine or Rushton turbine is a radial flow impeller used for many mixing applications (commonly for gas dispersion applications) in process engineering and was invented by John Henry Rushton. The design is based on a flat disk with vertical, flat blades vertically mounted.
What are the different types of turbine blades?
Turbine blades are classified into three types: Impulse, reaction, and impulse-reaction.
What properties are required for the material used for a gas turbine blade?
Modern turbine blades often use nickel-based superalloys that incorporate chromium, cobalt, and rhenium. Aside from alloy improvements, a major breakthrough was the development of directional solidification (DS) and single crystal (SC) production methods.
How are turbine blades attached to turbine discs?
A series of grooves or notches, conforming to the blade root design, are broached in the rim of the disk. These grooves allow attachment of the turbine blades to the disk; at the same time, space is provided by the notches for thermal expansion of the disk.
What are turbine discs made of?
In the past, turbine discs have been made in ferritic and austenitic steels but nickel-based alloys are currently used. Increasing the alloying elements in nickel extends the life limits of a disc by increasing fatigue resistance.
What is agitator in reactor?
An agitator is a device which is used to import motion in the form of stirring to the liquids or semi solids. The agitator is a device which contains a shaft and an impeller/propeller. The shaft is connected to the gear box and the assembly is driven by motors using electricity.
How new materials can improve gas turbines?
The advancements in coatings and cooling systems have enabled these materials to operate at temperatures as high as 1500°C. 2 Specific core power versus turbine rotor inlet temperature for gas turbine engines [3]. Additionally, weight reductions are also an important area of improvement.
What can cause turbine blade creep?
Turbine blade failure can have many causes, from exterior effects such as foreign object strikes material effects such as creep and fatigue. Often creep and fatigue work together to cause failure [81], for example small cracks caused by creep (grain boundary sliding) leading to low cycle fatigue failure [82] .
Where the blade is attached to the turbine?
Wind turbines consist of the blades attached to a hub, which is jointly called the rotor. The rotor is connected to a the nacelle, and the nacelle holds the key electrical and mechanical equipment at the top of the tower including the main shaft, gearbox and generator.
Why are turbine blades hollow?
Turbine blades contain rows of hollow aerofoils for cooling to increase the engine operating temperature. Cool air flows through the holes, which are located just below the surface, to remove heat from the superalloy.
What are slotted disc turbines used for?
The use of inexpensive slotted disc turbines in place of much more expensive bladed turbines can fill a void in the need to convert heat energy to electrical energy, and can help to reduce dependence on the electrical grid. Slotted discs may be used in other applications such as gas turbine and hydroelectric applications.
How to increase the diameter of a slotted disc turbine casing?
In the slotted disc turbine, it is not necessary to vary the diameter of the disc, and therefore the diameter of the casing. The same effect can be achieved by increasing the length of the slots, by changing the angle of the tabs, or a combination of both.
What is a set of discs in a turbine called?
A set of discs in a turbine is referred to as a disc-stack. There are theoretical limits as to how many discs can be added. Types of Discs. There can be two types of discs in a turbine, a rotor disc and a stator disc. The same fabrication method can be used to forms both types.
What is a slotted disc made of?
A slotted disc, illustrated in Fig. 1, is made from a round flat disk of sheet metal. Slits are cut along the radials of the disk and tabs are formed by expanding the metal on one side of the slit in such a manner as to form a tab, and therefore an opening through which steam can pass.