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superheated steam produces greater pressure and power and can go very long distances by itself compared to regular steam.
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Not quite. The pressure is no more than that at which it was generated in the boiler, because it is flowing through the superheater to the engine (reciprocating or turbine) - and indeed may be less if throttled through the regulator on the boiler outlet first. I'm not sure where "distance" comes from, but superheating raises the efficiency rather than power, by keeping the steam above its condensation temperature for the instantaneous pressure it passes through in expanding to do its work. This means it can act as a gas for a longer part of the piston stroke, or for further in its route through the many stages of a steam-turbine.
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Why not super heated steam used in nuclear power plant?
Actually, superheated steam is used in nuclear power plants. It is part of the goal of extracting the most energy possible from the steam cycle.
Is it possible to boil water by passing steam at atmospheric pressure?
If the steam is superheated, then yes - it can be used to boil water. If the steam is at the saturation point however, the most you could achieve would be to heat the liquid water to the boiling point while condensing some of the steam.
How is heat generated?
When water is heated, there is a relation between temperature and pressure at which the water and steam are in equilibrium. This applies up to 374 degC at which the corresponding pressure is 222 bar abs or 3220 psi abs. Beyond this temperature liquid water cannot exist and the steam is said to be supercritical. At any temperature between 100 degC and 374 degC there will therefore be a pressure at which steam is just formed and this is said to be dry saturated steam. It is saturated because if the temperature drops even slightly at the same pressure, steam will condense. If at this same pressure the steam is further heated, it is said to be superheated because it is at a temperature higher than dry saturated steam would be. Superheated steam is desirable for use in steam turbines, because it prevents formation of water droplets as the steam is expanded through the turbine-the droplets could damage the turbine blades. In the supercritical region above 374 degC steam will always exist whatever the pressure, so the concept of superheat does not apply here.
What the device used to increase the temperature of the saturated steam without increasing its pressure is called?
There is a small problem with the question: if you increase the temperature of saturated steam without increasing pressure, it will no longer be saturated - it will be superheated. With this in mind, it should be no surprise that the device that does this is normally called a "superheater". The picture accompanying this question is an example of a superheater.
Relationship of temperature of boiling water and temperature of steam?
In the case where heat is being added to generate steam from a container of water, as long as there is water still in the container, the temperature remains constant. It takes energy for water to change state into steam and all of the heat added goes to performing this task so the temperature stays the same, 212 degF (100 degC) at atmospheric pressure. While the water is boiling, the steam is "saturated," meaning any loss of heat would cause some of the steam to condense back into water. Once all of the water has been boiled and changed state, any additional heat supplied will cause the temperature to increase and the steam is "superheated," that is above its saturation temperature.
In order for a high temperature boiler or steam engine to produce superheated steam?
In order for a high temperature boiler or steam engine to produce superheated water, or steam?
Which type of steam is imparted on the blades of turbine?
Superheated steam.
What happens when superheated steam pressure is reduced?
steam quality increase
How much energy is used per kilogram of steam?
That would depend on if the steam is superheated dry steam or not and if superheated dry steam its temperature. It should be possible to google "boiler equations" or "boiler design" to get details.
Which is better wet steam or dry steam?
If by dry steam you mean superheated steam then dry steam because it has a higher calorific value
Is superheated steam suitable for air heaters instead of saturated steam?
No, superheated steam gives off little energy. Most of the heat given off by steam is the latent heat of condensation as it undergoes a phase change from vapor to liquid. Superheated steam could first be "desuperheated" by adding water until it reaches the saturation point, then used for heat transfer processes.
Why saturated steam is used in exchangers frequently rather then superheated?
The heat transfer coefficient of superheated steam is poor. Saturated steam has a better heat transfer coefficient, and also most of the heat transferred from steam occurs because of the condensation phase change.
Why is superheated steam used in power plant?
because if the steam is not superheated the remaining water droplets reduce efficiency and can cause corrosion and pitting. +++ Nearly! Saturated steam, as non-superheated steam is called, is really only steam at the pressure and temperature in the boiler. Once it starts to expand as a gas in doing its work, the pressure and temperature fall and condensation will set in, leaving less and less useful water-vapour to act as a gas. Hence, as you say, the efficiency falls.
What happen if you heat steam?
If you heat steam under pressure you get "superheated steam" under higher than original pressure
What is the meaning of super heat?
Superheated steam is steam at a temperature higher than water's boiling point
What is the difference between dry steam and wet steam to clean?
DRY steam is superheated There is a temperature below which steam will start to condense into water droplets. This is called the saturation temperature, and it varies with the pressure of the steam. Steam that is exactly at its saturation temperature is called saturated steam. Steam that is below its saturation temperature contains droplets of moisture and is called wet steam. Steam that is above its saturation temperature is called superheated steam.
What is the difference between saturated steam and Superheated steam?
Saturated steam occurs when steam and water are in equilibrium. If you have a closed container of water and heat it, above 100 celsius the steam pressure will start to rise, and as the temperature continues to rise, the pressure will go on rising. What is happening is that steam is being evolved to match the temperature (steam tables will give this relation) and the steam conditions are said to be saturated because if the pressure is raised by external means, some of the steam will start to condense back to water.If the steam pressure is held at a lower level than that achieved at saturation, by taking steam off to feed a turbine or other steam usage, there is effectively an excess temperature for that pressure, and the steam is said to be superheated. It in fact then becomes dry, and behaves as a gas. The amount of superheat can be quantified as so many degrees of superheat (celsius or fahrenheit).Turbine designers want steam to be superheated before reaching the turbine, to avoid condensation causing blade erosion, and steam producing boilers in power plants are designed to produce superheated steam. In plants where no turbines are used, only satured steam is normally generated.In heating applications, saturated steam is preferable, because it has a better energy exchange capacity. Superheated steam must cool down, and become saturated steam, before condensing in a heat exchanger. Also, superheated steam is a thermal insulator, like air.That is why it is necessary to direct superheated steam through a desuperheater before using the steam in heating applications.
