0
What else can I help you with?
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.
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.
Why is heat trasnfer coefficient of saturated steam is higher than superheated steam?
when steam is at its saturation point for a given pressure, any heat removed will cause liquid water to form. So when saturated steam is used to heat something else, the heated object/substance receives the condensation heat of the steam. The latent heat of condensation/evaporation is 970 But/lb @ 0 psig. On the other, superheated steam only gives up about 10 BTU/lb if it is cooled 20 degrees F. That means that much more steam would be used to transfer the equivalent amount of heat. The liquid water interface also improves the heat transfer.
What is the function of a superheater?
It is used to convert saturated or wet steam into dry steam for use in steam turbines, which are used for marine propulsion and the generation of electricity. +++ Also used for steam feeding reciprocating engines such as railway locomotives. It is not just a matter of dryness. Superheating allows the steam to work as a gas for longer during its passage through the turbine or cylinder, hence increasing the thermal efficiency of the whole plant.
Is thermodynamics a type of mechanical engineering?
Thermodynamics is a branch of physics that was started after there was a need to understand the energy in superheated steam, so that steam engines could be made as efficient as possible. So thermodynamic is definitely part of mechanical engineering because it is now used in the design of all kinds of engines, piston engines, turbines etc.
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.
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 not super heated steam used in nuclear power plant?
Superheated steam is not used in nuclear power plants because it can cause corrosion in the turbines. Additionally, using saturated steam allows for better control over the temperature and pressure in the system, enhancing safety and efficiency. Nuclear power plants typically operate with saturated steam to avoid these issues.
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.
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 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.
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.
Why is heat trasnfer coefficient of saturated steam is higher than superheated steam?
when steam is at its saturation point for a given pressure, any heat removed will cause liquid water to form. So when saturated steam is used to heat something else, the heated object/substance receives the condensation heat of the steam. The latent heat of condensation/evaporation is 970 But/lb @ 0 psig. On the other, superheated steam only gives up about 10 BTU/lb if it is cooled 20 degrees F. That means that much more steam would be used to transfer the equivalent amount of heat. The liquid water interface also improves the heat transfer.
What is a Binary Vapour Cycle?
A binary vapour cycle is a representation of a mercury cycle and a steam cycle on a same scale.In this vapour cycle there is comparison between the mercury cycle and steam cycle. In mercury cycle there occurs isothermal expansion of saturated water from boiler into dry saturated steam followed by isentropic expansion followed by condensation of steam and at last heating of steam and thus mercury has completed the cycle in 4 way process. In steam cycle first ther is isothermal expansion which results in converting of saturated water into dry saturated steam followed by superheated process where the steam is superheated followed by isentropic expansion of superheated steam followed by condensation of exhaust steam and at last heating of steam thus completing the cycle.
Why superheated steam in distillation column?
Superheated steam is often used in a distillation column to provide efficient heat transfer for the separation process. The high temperature of the superheated steam helps to vaporize the liquid components being distilled while maintaining a consistent temperature throughout the column. This can improve the overall separation efficiency and allow for better control of the distillation process.
How steam required for steam tracing of jacketed lines is calculated how much steam required for sulfur melting?
The steam required for steam tracing is calculated on the basis of the amount of heat transfer that is required or the temperature that you want to maintain with the help of steam. It also depends on the pipe material through which the steam is passing,the condition of the steam that whether it is saturated or superheated etc. Overall heat transfer cofficient is calculated considering all the factors like fouling or scaling,inside and outside dia. , surface area etc. After calculating the amount of heat to be transferred, the requirement of rate of steam is calculated. Generally, Low pressure steam is used as it has got more latent/Sensible heat as compared to MP or Superheated steam.
How can you use superheated steam to grow plants?
steam will kill just about any plant and superheat steam even more so. they are used for cleaning and disinfecting greenhouses and soil.
