Contents
What connects the turbine to the compressor?
Shaft — The shaft connects the turbine to the compressor, and runs most of the length of the engine. There may be as many as three concentric shafts, rotating at independent speeds, with as many sets of turbines and compressors. Cooling air for the turbines may flow through the shaft from the compressor.
How are aircraft turbine blades attached?
[Figure 1-63] The turbine wheel is a dynamically balanced unit consisting of blades attached to a rotating disk. The disk acts as an anchoring component for the turbine blades. Since the disk is bolted or welded to the shaft, the blades can transmit to the rotor shaft the energy they extract from the exhaust gases.
What are turbine discs?
Turbine discs are engine components manufactured from Titanium 64 or heat-resistant high-temperature alloys such as Inconel 718 and Udimet 720. These are complex workpieces with chambers and grooves that are rarely ideally accessible.
How are turbine discs manufactured?
Turbine discs are usually manufactured from a machined forging with an integral shaft or with a flange onto which the shaft may be bolted.
What is a impulse turbine?
The impulse turbine is the simplest type of turbine. It consists of a row of nozzles followed by a row of blades. The gas is expanded in the nozzle, converting the high thermal energy into kinetic energy.
What makes the discs in a disc turbine?
The compressor discs at the front end of the compressor are produced from titanium. The higher strength of titanium at the moderate operating temperatures at the front end of the compressor, together with its lower weight, provides a considerable advantage over steel.
How are the discs in a compressor made?
The compressor discs at the rear end of the compressor are produced from creep-resisting steels, or even nickel-based alloys, because of the high temperatures to which they are subjected. The compressor discs at the front end of the compressor are produced from titanium.
Where does the power for the compressor come from?
The power to drive the compressor comes from the turbine (see below), as shaft torque and speed. Bypass ducts deliver the flow from the fan with minimum losses to the bypass propelling nozzle. Alternatively the fan flow may be mixed with the turbine exhaust before entering a single propelling nozzle.
How are the casings of a gas turbine made?
H.P. compressor casings of the gas turbine engine are forged as rings or half rings which, when assembled together, form the rigid structure of the engine. They are produced in various materials, i.e., stainless steel, titanium, and nickel alloys.