Mechanical Engineering Assignment Help >> Theory of Turbines and Its Operations, Types of Turbines, Assignment Help

Live Experts: Theory and Operations of Turbines Assignment Help, Homework Help & Turbines Projects Assistance

Theory of turbines and its operations is a different subject in engineering courses. It is completely based on the learning of working process and operations of turbines. It is also included in electrical engineering course. The students are often struggling with turbines problems and numeric questions. There are applied many basic concepts of physics, mechanical engineering and electrical engineering, thus the subject needs more concentration in learning. We at Expertsmind.com offer theory of turbines and its operations assignment help, turbines homework help, mechanical engineering projects assistance and problems solutions with the best online support for 24*7 hours. Get solved turbines numeric questions and theoretical projects solutions at Expertsmind.com.

Turbines

A rotary engine which extracts energy from a fluid flow and then converts the energy into useful work is termed as turbine.

A simple design of a turbine contain as rotor assembly, which is the moving part, having shaft or drums with blades attached to them. The movement of the blades, which is caused by the flow of fluids, creates rotational energy which is imparted to the rotor. Some examples of turbines are water and wind mills.

The gas steam and water turbine consists of a casing around the blades which contains and controls the working fluids. The steam turbine was invented by Sir Charles Parsons and the impulse turbine was invented by Swedish engineer Gustaf De Laval. The modern steam turbines have both the impulse and reaction in the same unit. A pump or a compressor is a turbine operating in reverse. The term turbo is derived for Latin and was first used by Claude Bertin in the year 1828 and later his student Benoit Fourneyron built the first practical water turbine.

Theories of operations of turbines

A flowing or working fluid contains kinetic as well as potential energy and the fluid may be compressible as well as incompressible. The energy of these fluids is trapped by turbines in several ways.

Impulse turbines- The impulse generated by changing the direction of flow of high velocity fluid or gas jet is used to spin the turbine. This leaves the fluid flow with a decreased amount of kinetic energy. The fluid or gases in the turbine blades have no pressure change and the entire pressure drop takes place in the stationery blades. The fluid is accelerated using a nozzle, which changes its pressure head to velocity head. This is done before the fluid reaches to turbine. This process is used in De Naval turbines and Pelton Wheels. The transfer of energy in impulse turbines is described by Newton’s second law of motion.

Reaction turbines- A torque is developed in these turbines when they react to the gas or the fluid pressure or the mass. When the gas or fluid passes through the turbine rotor blades, the pressures in the system changes. The turbine must be fully immersed in the flowing fluid and the pressure casement is also provided for a working fluid. The primary function of the working fluid is to contain and direct the working fluid. It also maintains the functions imparted by the draft tubes in water turbines. This concept is used in most steam turbines including the Francis turbine. Newton’s third law is used to describe the transfer of energy in reaction turbines.

Various types of turbines

1. Steam turbines-For generation of electricity in thermal power plants, steam turbines are used. Coal fuel oil or nuclear power provides the primary source of energy. In initial times, the steam turbines were used as ship propellers.

2. Gas turbines-the construction of a gas turbine include inlet, fan compressor, nozzle and combustor and are also refereed to as turbine engines.

3. Transonic turbine-The gas flow in a transonic turbine is supersonic when it exits the nozzle guide vanes, though the downstream velocities become subsonic. These turbines are less efficient and more uncommon and operate at higher pressure ratio than normal.

4. Contra rotating turbines- It was invented by the Swedish engineer Fredrik ljungstorm in Stockholm, and is also known as ljugstorm turbine. It has a multi stage radial turbine which offers greater efficiency. It also has an extremely compact design and is widely successful in backpressure power plants.

5. Statures turbines- There is no intermediate set of stator vanes in the stator less turbine and the gas flow which is exiting an upstream motor directly impinges onto a downstream rotor.

6. Ceramic turbine- Ceramic blades are used in these turbines in place of the nickel based alloys blades. Ceramic blades have much more brittleness and thus are more risky as a catastrophic blade failure can occur. Thus they are used only in gas turbines and jet engines.

7. Shrouded turbines- Some turbine blades have shrouding at their top which interlocks with adjacent blades and increases damping which reduces the flutter of the blade. In some large electricity generation turbines which are land based this shrouding is complemented with lacing wires. The lacing wires help in reducing the chances of blade failure in both high and low pressure turbines.

8. Bladeless turbine –they use the boundary layer effect instead of a fluid impinging on the blades, which is the common case unconventional turbine.

9 wind turbines-they operate as a single stage without using nozzle and other interstage guide vanes.

11 Water turbines-the Francis water turbine is the most widely used turbine with its other variant known by the name of Kaplan turbine. The Pelton turbine is a type of impulse water turbine.