What is the function of reheater in gas turbine?
What is the function of reheater in gas turbine?
When a gas turbine plant has a high pressure and low pressure turbine a reheater can be applied successfully. Reheating can improve the efficiency up to 3 % . A reheater is generally is a combustor which reheat the flow between the high and low pressure turbines. In jet engines an afterburner is used to reheat.
What is the function of reheater?
A reheater is basically a superheater that superheats steam exiting the high-pressure stage of a turbine. The reheated steam is then sent to the low-pressure stage of the turbine.
What is reheater gas turbine?
In a gas turbine, reheating is a process in which the hot gases coming out of the combustion chamber expands in two turbines i.e. high pressure and low pressure turbine. The hot gases firstly expands in a high pressure turbine then passes through a heat exchanger and then expands in the low pressure turbine.
How a use of reheater increase the work output in between the turbine?
In reheating type boiler-turbine plant the heat/energy transferred into the steam per kilo is higher and enthalpy loss in condenser is relatively lower (it is always constant kJ/kg). One kilo of steam can work more. That also explains why it is more efficient to tap steam of low pressure part for condense preheating.
What is the maximum temperature of gas turbine?
1,600 degrees Celsius
What is the function of intercooler in gas turbine?
An intercooler is a mechanical device used to cool a gas after compression. Compressing a gas increases its internal energy which in turn raises its temperature. An intercooler typically takes the form of a heat exchanger that removes waste heat in a gas compressor.
Why Brayton cycle is used in gas turbine?
The Brayton Cycle is a thermodynamic cycle that describes how gas turbines operate. The idea behind the Brayton Cycle is to extract energy from flowing air and fuel to generate usuable work which can be used to power many vehicles by giving them thrust.
What is the function of regenerator in gas turbine?
Regenerators can be used for exhaust-gas heat exchange or for intercooling in gas-turbine systems. As an exhaust-gas heat exchanger, a regenerator recovers heat from the exhaust and uses it to preheat the compressed air before the compressed air enters the combustor.
What is the difference between gas turbine and steam turbine?
The primary difference between steam and gas turbines is the fact that steam turbines receive power from expanding steam. Fuels such as natural gas can heat condensed water in a boiler, but it’s also possible to utilize renewable thermal energy for this heating. This water-based cycle is the Rankine Cycle.
Where the gas turbines are used?
Gas turbines are used to power aircraft, trains, ships, electrical generators, pumps, gas compressors, and tanks.
What are the advantages of gas turbine over steam turbine?
Advantages of Gas Turbine Power Plants over Steam Plants No ash handling Low capital cost and running costs Space requirement is less Fewer auxiliaries are used Can be built relatively quicker Can brought on load quickly to support peak loads Thermal efficiency of the gas turbine is higher than steam when …
What are the advantages and disadvantages of gas turbines?
Power Generation/Gas Turbine Power
Advantages | Disadvantages |
---|---|
Less water used since there is no need for a condenser | Temperature of combustion chamber is too high thus resulting in a lower life. |
Maintenance charges are low | . |
Can be started quickly | . |
No stand-by losses | . |
What is the main disadvantage of gas turbine?
The main disadvantage of gas turbines is that, compared to a reciprocating engine of the same size, they are expensive. Because they spin at such high speeds and because of the high operating temperatures, designing and manufacturing gas turbines is a tough problem from both the engineering and materials standpoint.
What are limitations of gas turbine?
Disadvantages: Limited efficient rpm range, expensive to manufacture, poor fuel economy and power at low speed, slow to respond to acceleration from low speed, requires vast amounts of air with huge, high temperature exhaust gas flow, high noise level.
Why is power generation by gas turbines attractive these days?
The economics of power generation by gas turbines is proving to be more attractive, due to low capital cost, and high reliability and flexibility in operation. The initial cost and operating cost of the plant is lower than an equivalent steam power plant. A thermal plant of 250 MW capacity cost about Rs. 250 crores.
How efficient is a gas turbine engine?
Latest generation gas turbine engines have achieved an efficiency of 46% in simple cycle and 61% when used in combined cycle.
What is the efficiency of a gas turbine?
A simple cycle gas turbine can achieve energy conversion efficiencies ranging between 20 and 35 percent. With the higher temperatures achieved in the Department of Energy’s turbine program, future hydrogen and syngas fired gas turbine combined cycle plants are likely to achieve efficiencies of 60 percent or more.
Why is gas turbine efficiency so low?
The compressor efficiency decrease is due primarily to the effects of compressor fouling. Any reduction in the turbine efficiency is due to the decrease in the turbine non-dimensional speed resulting from the increase in the turbine entry temperatures, as observed in Fig. 18.15.
How can you increase the efficiency of a gas turbine?
1) Increase the turbine inlet temperature provided the turbine materials can stand the temperature or one has access to replacement parts that can withstand the temperatures. 2) Increase the pressure ratio. There is a limit to the efficiency increase depending upon the turbine inlet temperature.
Which fuel is used in gas turbine?
Most recent answer. The cleanest fuel is hydrogen. But hydrogen is very expensive to produce. A hydrogen gas turbine is very economical.
How can I improve my gas turbine performance?
IMPROVING OUTPUT Inlet conditioning – reducing the inlet air temperature is a very common method for improving gas turbine output. There are three well known methods for achieving this output improvement: fogging, evaporative cooling, and chilling.
What is heat rate of gas turbine?
Heat rate is one measure of the efficiency of electrical generators/power plants that convert a fuel into heat and into electricity. The heat rate is the amount of energy used by an electrical generator/power plant to generate one kilowatthour (kWh) of electricity.
Which one is not component of gas turbine?
2. Which of the following is not used in gas turbine power plant? Explanation: Natural gas itself or mixture of natural gas and air is used as working medium in gas turbine power plant. Condenser is a device or arrangement used to condense low pressure steam already used by turbine.
What are the major field of application of gas turbine?
Explanation: A Gas Turbine has applications in nearly all fields, the major ones being in the fields of Aviation, Oil & Gas industry, Marine propulsion.
What are the 3 main component of gas turbine?
Gas turbine overview. The gas turbine has three major sections, namely the compressor, combustor and turbine (although, from a materials perspective, the other major component groups – rotor, casing and auxiliaries – are also of interest).
What is the main challenge in the development of gas turbine?
Environmental challenges with gas turbines include low levels of NOx, CO and soot amongst other pollutants. Specifically, ultra-low NOx combustor technology is required to meet the ozone depletion challenge. Researchers are facing concerns about the development of dry low-NOx stationary and aero engines.
What is the working principle of gas turbine?
The gas-turbine operates on the principle of the Brayton cycle, where compressed air is mixed with fuel, and burned under constant pressure conditions. The resulting hot gas is allowed to expand through a turbine to perform work.
What are the four type of gas turbine?
Four types of gas turbine engines are used to propel and power aircraft. They are the turbojet, turbofan, turboprop, and turboshaft.
What is gas turbine engine and its function?
The gas turbine is an internal combustion engine that uses air as the working fluid. The engine extracts chemical energy from fuel and converts it to mechanical energy using the gaseous energy of the working fluid (air) to drive the engine and propeller, which, in turn, propel the airplane.
What are the three main components of gas turbine explains their functions?
comprised of three main sections: a compressor, a combustor, and a power turbine. hot gas is allowed to expand through a turbine to perform work. interaction between the gas and the blades. components of both types are the air compressor, a combustor, and the turbine.