What is Steam: Definition and 535 Discussions

Steam is water in the gas phase. This may occur due to evaporation or due to boiling, where heat is applied until water reaches the enthalpy of vaporization. Steam that is saturated or superheated is invisible; however, "steam" often refers to wet steam, the visible mist or aerosol of water droplets formed as water vapour condenses.
Water increases in volume by 1,700 times at standard temperature and pressure; this change in volume can be converted into mechanical work by steam engines such as reciprocating piston type engines and steam turbines, which are a sub-group of steam engines. Piston type steam engines played a central role in the Industrial Revolution and modern steam turbines are used to generate more than 80% of the world's electricity. If liquid water comes in contact with a very hot surface or depressurizes quickly below its vapor pressure, it can create a steam explosion.

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  1. S

    Utilizing to generate power of excess 60# steam

    Is it possible to use 60# steam to generate electrical power. Regards,
  2. N

    Calculating Efficiency of a Steam Turbine at Varying Temperatures

    Homework Statement A steam turbine takes vapor at 463 deg c and exahusts it to a steam boiler at 238 deg c. the turbine then receives a steam from the boiler at this temperature and exhausts it to a condenser at 38 deg c. what the is the maxumim efficiency of this combination. Homework...
  3. K

    Dryness Fraction and Entropy Generation in Non-Isentropic Steam Expansion

    Homework Statement I place the question first: Superheated steam at an absolute pressure of 10 bar and temperature of 340C expands in a nozzle reversibly and adiabatically until the pressure is 0.1 bar. the mass flow rate is 4.2kg/s. The questions asking for: 1) Drawing the appropriate...
  4. L

    Calculating Composition & Temp of Mixture After Adding Steam & Ice

    Homework Statement One kg of steam at 100 degrees Celsius is added to 1 kg of ice at 0 degrees Celsius. What is the composition and temperature of the resulting mixture. The heat of fusion for water is 79.7 kcal/kg, the heat of vaporization is 539 kcal/kg, and specific heats of ice and water...
  5. A

    Calculating Water and Steam Temperatures

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  6. J

    Solving a Steam Engine Flywheel Angular Displacement Problem

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  7. R

    Low Cost Clay/Ceramic Steam Engine

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  8. T

    Thermodynamics: Final temp of Ice + steam?

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  9. B

    Hot water / cold steam interaction

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  10. M

    Thermodynamics: Steam Power Plant

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  11. I

    A few questions about steam, water vapor, and humidity

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  12. S

    Choice of steam Turbine/Expander?

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  13. S

    Troubleshooting Simple Steam Problems: Tank Capacity and Temperature"

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  14. V

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  15. C

    I am having trouble understanding a steam turbine

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  16. C

    Steam quality, mass flow rate, temperature and pressure of the steam

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  17. M

    Steam system pipe sizing inquiry

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  18. N

    Ethene + Steam = Ethane and perhaps a magical unknown substance

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  19. J

    Calculate Heat Removed from 130 g Steam to Ice

    Homework Statement How much heat must be removed when 130 g of steam at 145°C is cooled and frozen into 130 g of ice at 0°C. (Take the specific heat of steam to be 2.01 kJ/kg·K.) Answer is in kcal. Homework Equations The Attempt at a Solution I know steam turns back into...
  20. G

    [thermo] pressure & steam tables related question

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  21. L

    Find mass of steam using the 'Ideal Gas Equation'.

    Show that there is a mass of (4.8 x 10^-3)kg of steam above the water when the temperature is 122 Celcius? Volume of Steam = 4.2 x 10^-3 (metres cubed) Pressure of steam= 2.1 x 10^-5 (Pa) molar mass of water = 18g per mole molar gas constant = 8.3 Joules/mol/K Homework...
  22. S

    Complete vaporization time of water into superheated steam - DESUPERHEATER

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  23. T

    How much heat is required to convert ice into steam?

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  24. R

    What Is a Reaction Turbine with a Velocity-Compounded Impulse Stage?

    Homework Statement Sketch and describe a reaction turbine with a velocity-compounded impulse stage. Homework Equations The Attempt at a Solution Would anyone happen to know where I could find this?? Link?
  25. M

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  26. T

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  27. K

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  28. K

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  29. I

    Shark Steam Mop: 3 Mo. Experience & Tips

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  30. R

    Steam Tables For Apple Computers

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  31. R

    Steam Tables For Apple Computers

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  32. N

    Why Does Entropy Behave Differently in Water and Steam with Temperature Changes?

    Homework Statement Why does the entropy of the water increase with increasing temperature, while the entropy of steam decreases, while the entropy of steam decreases with increasing temperature? The Attempt at a Solution I think the reason why the entropy increases with water is because...
  33. H

    Steam vs Water Heat: Which is More Dangerous?

    Homework Statement Will 1ml of 100 degrees C water or 1ml of 100 degrees C steam be more dangerous to your skin? Homework Equations not too sure The Attempt at a Solution I keep hearing that steam would be more lethal than the water but I would like some math to back it up. What math...
  34. M

    Steam jet refrigeration , mini project

    im from India , in my third year of B.E. Mech degree .. course... and my group is planning to do steam jet refrigeration system...as a MINI PROJECT ( Design And Fabrication Project in the syllabus).. the components of the project are - 1. boiler 2. steam nozzle 3. thermocompressor 4...
  35. F

    Steam Generation with Microwaves

    Hello reader, I was heating some coffee in the microwave oven today when I had an idea come to me. Is it Possible to heat water with microwaves, (dielectric heating) to superheat water? Then allow it to form to steam, turn that steam into dry steam. And then use that to turn a generator...
  36. P

    Help needed with heat loss calculation from a steam pipe please

    I’m an entrepreneur in South Africa with the rights to a type of insulating coating. It’s new on the market here and no real research and development has been done on the coating to determine how much energy it can save. I’m a marketer and I don’t have the educational background to answer this...
  37. P

    How Can Efficiency Be Maximized in a Velocity Compounded Impulse Steam Turbine?

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  38. P

    Calculating Exit Temperature of Steam Through a Valve

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  39. S

    Effect of variation of steam supply

    Hi, I am doing my revision and one of the question got me thinking but I am not sure if I got it right. The question asks what is the effect of variation of steam supply on power output,power factor,armature current and load angle of the synchronous machine. I think reduced in steam...
  40. G

    How Much Coal Must Be Burned in a Steam Power Plant to Generate 900 MW?

    Homework Statement 18. (II) At a steam power plant, steam engines work in pairs, the heat output of the first one being the approximate ehat input of the second. Th eoperating temeprautres of the first are 680 degrees C and 430 degrees C, and of the second 415 degrees C and 280 degrees C...
  41. M

    Top High Torque Low Pressure Steam Power Generators for 1kW Output

    Does anyone know a suitable engine / turbine / expander that can run under 2 bar (30 PSI) of pressure and generate upto 1 kw power output? Basically a high torque, low pressure...i have been searching like crazy everywhere, cannot find anything...Also will a manufactured tesla turbine be able to...
  42. L

    Need help with latent heat involving ice and steam

    Homework Statement A well-insulated bucket of negligible heat capacity contains 177 g of ice at 0°C. (a) If 20 g of steam at 100°C is injected into the bucket, what is the final equilibrium temperature of the system? I've already solved this part to be 0 degrees Celsius. (b) What...
  43. S

    Thermodynamics: Steam Powered Carnot Engine Question

    Homework Statement A steam engine has a cylinder 80cm in diameter with a piston that has a total travel length of 1.8m. Assume that there is no "dead space" between the cylinder head and the piston when the piston is farthest in the cylinder. Steam is piped into the cylinder head from an...
  44. M

    Calculating Heat Required to Change 1.0 kg of Ice to Steam

    Homework Statement How much heat in kcal is required to change 1.0 kg of ice, originally at -30 degrees C, into steam at 120 degrees C? Assume 1.0 atm of pressure. (Please use the following values for the constants needed in the problem: Latent heat of fusion=79.7 kcal/kg; Specific heat of...
  45. H

    How can I improve the design of my steam power plant for optimal efficiency?

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  46. S

    Is Saturated Steam Pressure the Same as Saturated Vapor Pressure?

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  47. A

    What Is the Resistivity of Pure Steam?

    I am working on a Project that involves determination of Quality of Steam. In that I have few queries, so please help if possible: 1. Is there any mathematical relationship between Resistivity of water and temperature? because i am not able to find one, but since i am working on this...
  48. G

    Chem: Why more heat released from steam than liquid water?

    I was sick so I actually missed this lesson in class and this wasn't mentioned in the notes I got from a fellow student, nor is it in my textbook. I can't even find a definition for what it means that the heat of condensation is "evolved," so if anyone can fill me in on that I'd greatly...
  49. C

    Calculating Steam Consumption for Heating Curry Sauce | Heat Transfer Rate

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  50. leviterande

    Steam Powered VTOL: Exploring an Efficient Air Compression Method

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