What type of combustion system is there in gas turbine?

What type of combustion system is there in gas turbine?

Type of combustion chamber. The diffusion and premixed flame are two main type of combustion, which are using in gas turbines. Apart from type of flame, there are two kind of combustor design, annular and tubular.

How are turbine blades cooled?

Cooling is achieved by passing the air through these passages from hub towards the blade tip. This cooling air comes from an air compressor. In case of gas turbine the fluid outside is relatively hot which passes through the cooling passage and mixes with the main stream at the blade tip.

What are the two main types of turbine?

There are two main types of hydro turbines: impulse and reaction. The type of hydropower turbine selected for a project is based on the height of standing water—referred to as “head”—and the flow, or volume of water, at the site. Other deciding factors include how deep the turbine must be set, efficiency, and cost.

What is the head of a turbine?

Head is the change in water levels between the hydro intake and the hydro discharge point. It is a vertical height measured in metres. The two diagrams below show how the head would be measured on a typical ‘low head’ and a typical ‘high head’ site.

Which turbine is used for 200m head?

Explanation: Kaplan turbine is reaction turbine and it operates at low head 10-70 meters and output power is 5-200 MW. Explanation: Francis turbine is also reaction turbine but pressure energy is less when compared with Kaplan turbine . hence head is between 40 and 600 meters.

Which turbine is best for low head and high flow rate?

Turbines and Efficiency A Pelton design, for example, works best with high Head. A Crossflow design works better with low Head but high Flow. Likewise, other turbine types such as Francis, Turgo and Kaplan, each have optimum applications.

What is specific speed of turbine?

The specific speed value for a turbine is the speed of a geometrically similar turbine which would produce unit power (one kilowatt) under unit head (one meter). The specific speed of a turbine is given by the manufacturer (along with other ratings) and will always refer to the point of maximum efficiency.

Which turbine rotates faster for a given head and flow condition?

A special case of the propeller turbine is the Kaplan. In all these cases, specific speed is high, i.e. reaction turbines rotate faster than impulse turbines given the same head and flow conditions. The Francis turbine is suitable for medium heads, while the propeller is more suitable for low heads.

What is high and low head?

Low head,medium head,high head. Though there is no rule regarding water head height but below 30 meters is considered as low head,above 30 meters to 300 meters is called medium head and above 300 meters is known as high head hydro electric power plant.

Why is head hydropower low?

Low head hydropower is typically installed close to areas where the energy is needed, preventing the need for large electrical transmission lines.

What is head loss in a penstock?

The head loss in penstock comprises of friction loss (hf) due to resistance offered by penstock inner surface and other losses. As the head loss at trash rack is not dependent on the flow velocity in the penstock and is not considered for the optimum design of penstock.

How is penstock thickness calculated?

The diameter of the pipe /penstock (Dp) = 1.6 m (1600 mm) Pipe thickness (e) = 9 mm(which will be in the analysis) Penstock length (Lp) = 66 m….

1. K = bulk modulus of water 2.1×10^ 9 N/m2.
2. E = modulus of elasticity of pipe material 206 * 10^9 (N/m2)
3. D = pipe diameter 1600 mm.
4. e = wall thickness 6 mm.
5. L = length of pipe, 66 m.

What is called as exposed penstock?

Exposed penstocks are installed above the terrain surface and supported on piers (briefly called supports or saddles). The main advantage of exposed penstocks is the possibility of continuous inspection during operation.

Which type of penstock is less expensive?

A short straight penstock is least expensive.

What material is a penstock made of?

Generally, they are made of steel and water under high pressure flows through the penstock. They are a vital component of a hydroelectric facility that allows water to move to the turbine. Grates or filters can be attached to the ends of penstocks to trap large debris such as branches.

What material is used for making penstocks?

For high head penstocks, steel is the only material that should be used, but the required steel strength must be determined. At lower heads, wire wound wood stave, banded wood stave, fiberglass, plastic, concrete and mild steel can all be used.

Which is the major loss in flow through the penstock?

The various hydraulic losses which occur from penstock intake to power house are (1) entrance losses, (2) friction losses in pipe, (3) losses due to bends, (4) losses due to expansion joints, and (5) losses due to other appurtenances and fittings such as reducers, expanders, valves, dismantling joints, and manholes ( …

What is the purpose of penstock?

A penstock is a sluice or gate or intake structure that controls water flow, or an enclosed pipe that delivers water to hydro turbines and sewerage systems. The term is inherited from the earlier technology of mill ponds and watermills.

What is penstock and its types?

Penstocks or sluice gates are the equivalent of valves used in open channels (though both of these terms are sometimes used to mean other hydraulic control devices and structures). There are types in which flow goes over the gate (weir penstocks), and types where flow goes under the gate (submerged sluice gates).

Which principle is used in hydraulic turbine?

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