Turbomachinery Assignment Help




Turbomachinery, in mechanical engineering, describes machines that transfer energy between a rotor and a fluid, including both turbines and compressors. While a turbine transfers energy from a fluid to a rotor, a compressor transfers energy from a rotor to a fluid. The two types of machines are governed by the same basic relationships including Newton's second Law of Motion and Euler's energy equation for compressible fluids. Centrifugal pumps are also turbomachines that transfer energy from a rotor to a fluid, usually a liquid, while turbines and compressors usually work with a gas

Turbomachines are also categorized according to the type of flow. When the flow is parallel to the axis of rotation, they are called axial flow machines, and when flow is perpendicular to the axis of rotation, they are referred to as radial (or centrifugal) flow machines. There is also a third category, called mixed flow machines, where both radial and axial flow velocity components are present. Turbomachines may be further classified into two additional categories: those that absorb energy to increase the fluid pressure, i.e. pumps, fans, and compressors, and those that produce energy such as turbines by expanding flow to lower pressures. Of particular interest are applications which contain pumps, fans, compressors and turbines. These components are essential in almost all mechanical equipment systems, such as power and refrigeration cycles.

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a Secondary Flow is a relatively minor flow superimposed on the primary flow, where the primary flow usually matches very closely the flow pattern predicted using simple analytical techniques and assuming the fluid is inviscid. (An inviscid fluid is a theoretical fluid having zero viscosity.) The primary flow of a fluid, particularly in the majority of the flow field remote from solid surfaces immersed in the fluid, is usually very similar to what would be predicted using the basic principles of physics, and assuming the fluid is inviscid. However, in real flow situations, there are regions in the flow field where the flow is significantly different in both speed and direction to what is predicted for an inviscid fluid using simple analytical techniques. The flow in these regions is the secondary flow. These regions are usually in the vicinity of the boundary of the fluid adjacent to solid surfaces where viscous forces are at work, such as in the boundary layer.

A turbocharger, or turbo, is a gas compressor used for forced induction of an internal combustion engine. A form of supercharger, the turbocharger increases the pressure of air entering the engine to create more power. A turbocharger has the compressor powered by a turbine which is driven by the engine's own exhaust gases rather than direct mechanical drive. This allows a turbocharger to achieve a higher degree of efficiency than other types of forced induction compressors which are more vulnerable to parasitic loss.

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The Exoskeletal Engine (ESE) concept represents a paradigm shift in turbomachinery design. Current gas turbine engines have central rotating shafts and discs and are constructed mostly from heavy metals. They require lubricated bearings and need extensive cooling for hot components. They are also subject to severe imbalance (or vibrations) that could wipe out the whole rotor stage, are prone to high- and low-cycle fatigue, and subject to catastrophic failure due to disc bursts from high tensile loads, consequently requiring heavy containment devices. To address these limitations, the ESE concept turns the conventional configuration inside-out and utilizes a drum-type rotor design for the turbomachinery in which the rotor blades are attached to the inside of a rotating drum instead of radially outwards from a shaft and discs.