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Why is heat trasnfer coefficient of saturated steam is higher than superheated steam?
Ashankey
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.
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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.
What happen if you heat steam?
If you heat steam under pressure you get "superheated steam" under higher than original pressure
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
Would a laminar flow element a venturi a flow nozzle or an orifice plate produce the smallest total head loss?
The lowest head loss is from a venturi since it has the lowest coefficient of discharge. typical coefficients range from 0.95-0.99 where the higher coefficient is directly proportional to larger square root of Reynolds number.
What happens to the resistance of silicon as its temperature increases?
A: As temperature increases its resistance increases. Like all silicon diodes it will reach a point where the temperature coefficient is zero but it is at such elevated temperature to make it invaluable
What is a desuperheater?
HiSuperheated steam is steam that is at a temperature higher than the saturation temperature for the steam pressure. For example, steam at a pressure of 3 bar g has a saturation temperature of 143.762°C. If further heat were to be added to this steam and the pressure remained at 3 bar g, it would become superheated.So, desuperheating is the process by which superheated steam is restored to its saturated state, or the superheat temperature is reduced.The idea behind desuperheating is that saturated steam has a better energy exchange capacity (U coefficient) than superheated steam.Superheated steam must cool down before condensing, therefore it is less efficient than saturated steam in appliances such as heat exchangers.Also, superheated steam is a thermal insulator, just like air.
Why is the superheated vapor from the condenser is higher than the superheated vapor going into the compressor?
becaause it was just compressed by the compressor and is the high side of the system before the tex valve
The lower the phenol coefficient is the stronger the disinfectant is?
No,, the higher the phenol coefficient the stronger the disinfectant
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.
What is the meaning of super heat?
Superheated steam is steam at a temperature higher than water's boiling point
Which one has higher saturated fats lard or olive oil?
Lard has more saturated fats
What is the physical significance of damping coefficient?
The damping coefficient applies both to hydraulic circuits and springs. Hydraulics In general, higher the coefficient or viscosity higher is the tendency to ensure steady flow and hence a higher system efficiency. This is governed by the properties of hydraulic oil selected for use. Springs Higher the coefficient, greater is the tendency for a spring to reach a desired equilibrium position. This is governed by the properties of spring material selected for the applciation.
What value of the coefficient of friction the greater the resistance to sliding?
higher
The the value of the coefficient of friction the greater the resistance to sliding.?
higher
The value of the coefficient of friction the greater the resistance to sliding?
higher
What happen if you heat steam?
If you heat steam under pressure you get "superheated steam" under higher than original pressure
Saturated fats are liquid at room temperature?
saturated fats turn to liquid at room temp and higher but otherwise they are solid
