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. J

    Using Rogers & Mayhew Steam Tables to Calculate Internal Energy Change

    Well, I am studying for my engineering thermodynamics exam, and i don't seem to have written down some of the information about steam tables. Im fairly confident using them, except i can't remember the exact formulas we use to get the numbers in between the numbers given. For example, i have...
  2. C

    Where Can I Find a Basic 3D Model of a Steam Turbine for Simulation?

    Hello I am new to these forums and probably will be here for a long time. I am looking for a 3D model of a steam turbine I can play with in either CATIA, ANSYS, or Solidworks. I just want to run thermodynamic simulations and not modify any mechanical or structural components. I have been looking...
  3. A

    Work done by steam in cylinder

    Hellow, I came upon this problem when working out the power developed in the cylinder of a double-acting steal engine. A brief explanation of the motion of the piston in a reciprocating engine is neccessary; In the simple case of a crank revolving at a constant rate, say one rpm, the piston is...
  4. S

    Heating Water Beyond Super-Heated Steam: A Middle-Schooler's Question

    Hello I am not a science scholar but just a gifted middle-schooler. Anyway i was wondering, is it possible to heat water past super-heated steam? If it does then what does it turn into? And please don't mock me if this is a stupid question because I see the forums and see over-complicated...
  5. K

    Calculating Heat Discharge in a Steam Engine: Efficiency and Work Rate Analysis

    Homework Statement If a steam engine operates at half of its theoretical maximum efficiency, and does work at a rate of W J/s, calculate how much heat is discharged per second. The Attempt at a Solution emax = W/QH (Carnot) emax = W/2QH --> QH = W/emax Wrong answer. What...
  6. JaredJames

    Learn How to Use Steam Tables for Aerospace Engineering Exam

    hi, i am a first year aerospace engineering student and have just completed the Thermodynamics section of my course. My problem is, that i understand all topics except steam tables. I have absolutely no idea how to use them, and no idea what the calculations associated with them are. (e.g...
  7. T

    Latent heat, steam and ice question

    [SOLVED] Latent heat, steam and ice question Homework Statement 14g of steam at 100C is added to 47g of ice at 0.0 degrees C. a) Find the amount of ice melted and the final temperature. Homework Equations Q=mL Q=mc\DeltaT Q(hot)=-Q(cold) The Attempt at a Solution Ordinarily, in...
  8. P

    Steam turbines, maximum amount of work done?

    Steam turbines, maximum amount of work done? Hi, having a little trouble with this problem, not entierly sure what formula to use, or what value to use for Q. A steam turbine is operated ith an input temp of 800C and exhaust temp of 150C. What is the maximum amount of work the turbine can do...
  9. A

    Thermodynamics - Steam and Two Phase Systems

    Steam at a pressure of 1.25 MN/m² and with a dryness fraction of 0.96 flows through a steam mains of 150mm diameter with a velocity of 26 m/s. The steam is throttled to 0.12 MN/m². After throttling, 5kg of steam is blown into a tank of 98kg water, the original temperature of which is 16ºC. Take...
  10. D

    Is Producing High Temperature, High Pressure Steam Safe for Experimental Use?

    Hi there, I have a safety question. I want to produce high temperature, high pressure steam. On a 1/2 inch tube, length is about 1 meter. Initially I put cold water in tube. Then pump it to 4000 psi. Now I will heat it to achieve about 380C. (in this process, I will open a purge valve many...
  11. S

    Calculating Latent Heat of Steam: Mass, Temp & Thermal Capacity

    Homework Statement Ive been tasked with working out the Latent heat of steam the following are all my results and values used. Mass of the calorimeter and stirrer: 0.068Kg Thermal Capacity of the Calorimeter and Stirrer : 25.772 JK-1 Mass of water and Calorimeter and stirrer: 0.145Kg...
  12. S

    How does a nozzle work (in a steam turbine)?

    Hello, For sometime now I've been into electronics and i have forgotten most of my meager knowledge in thermodynamics. . Could you explain how a convergent-divergent nozzle works ? Steam at high temperature and high pressure but relatively low speed enters into the nozzle. Then why...
  13. V

    How Do You Calculate the Requirements for a Steam Plant Using Waste Gas Heating?

    I desperately need help with a equation. During a planning stage of a steam plant it was determent that 21 650 kg steam per hour at a pressure of 0.5 MPa and a temperature of 200 deg C were required.The available feed water temperature is 34,6 deg C.The efficiency of the plant is 70% and wast...
  14. M

    Steam Tables for Water - Specific Volumes & Enthalpies

    Can anybody post a link for the steam tables of water? Any would work that have specific volumes of the gas and liquid phases at all temperatures, and also have the specific enthalpies of each phase at each temperature. thanks.
  15. B

    How Can I Build a Biomass Steam Generator Using Coco Shells?

    Please help me, this is urgent. Anyone who has a sample of design and construction of a cocoshell feed steam generator? or site/s where i can find complete data in the design of the said steam generator?
  16. M

    Grams and volume of steam needed to raise the temperature of expresso

    [SOLVED] Grams and volume of steam needed to raise the temperature of expresso Homework Statement The temperature of espresso coffee (mostly water) can be increased by blowing 100°C steam into it. How much steam (in grams) is needed to heat up a 13 cm3 cup of espresso from 46°C to 82°C...
  17. R

    Heat released from condensing steam

    Homework Statement How many grams of ice at 0 degrees Celsius can be melted by the heat released when one gram of steam condenses to water at 100 degrees Celsius? Homework Equations Latent Heat of Fusion of Water: 334 J/g Latent Heat of Vaporization of Water: 2256 J/g Specific Heat...
  18. A

    Reaction vessel v Steam pressure

    Hello folks I am building a reaction vessel that will have an inbuilt condenser for a design project at the Saint Martiin`s school of fashion in London. Problem is, I know nothing about physics. would anyone help me out on what and how I calculate the necessary elements that will prevent the...
  19. M

    The properties of Superheated steam

    Looking at the steam tables I see that the entrolpy of steam at a constant temperature increases with a decrease in pressures. As an example, Steam at a temperature of 1000 degrees has an entrolpy 1520 @ 500 PSI. The same temerature steam at a pressure of 2000 PSi holds less energy...
  20. OmCheeto

    Is a Gasoline Engine with Water Spray Cooling Feasible?

    Has anyone heard of a gasoline engine that instead of using a water jacket for cooling, uses a spray of water to cool the cylinder? I was thinking along the lines of installing a bank of water spray injectors around the cylinder to remove the heat, which creates steam which can be further heated...
  21. D

    Another HELP problem: Steam to Ice

    Another URGENT HELP problem: Steam to Ice Homework Statement How many J of energy must be removed when 127.0 g of steam, at a temperature of 153.0°C, is cooled and frozen into 127.0 g of ice at 0°C? Take the specific heat of steam to be 2.1 kJ/(kg·K). Homework Equations Q1 = mc(delta...
  22. T

    Energy lost in conversion of steam to ice

    Homework Statement How many J of energy must be removed when 145.0 g of steam, at a temperature of 188.0°C, is cooled and frozen into 145.0 g of ice at 0°C? Take the specific heat of steam to be 2.1 kJ/(kg·K). Homework Equations Q=m*L The Attempt at a Solution Energy =...
  23. O

    Appropriate thermocouple in measuring superheated steam

    i want to know which type of thermocouple is used in measuring superheated steam temperature coming out of boiler? this temp sensor is used in accordance with desuperheater to reduce the temperature of excessive superheated steam... can u provide with its range, accuracy, and resolution
  24. P

    Solving the Steam & Ice Temperature Problem - Need Help!

    I have this problem, but I could not understand. pls help Steam at 100 degree celsius is added to ice at 0 degree celsius. The mass of the steam is 10 g and the mass of the ice is 50.0 g. What is the final temperature of the mixture? thanks a lot.
  25. D

    How to create a solor powered working steam turbine?

    I have my solar power planned out...1200 2 inch mirrors on plywood that will be aimed at the sun and will have a focal pint about 4 feet from the board. i know how to make the steam system but i haven't a clue how to make a working turbine to create electricity. (steam will be the way of...
  26. A

    Steam Ejector Design Resources

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  27. M

    Can a Steam Engine Be Made with Carbon Fiber Components?

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  28. N

    Another nasty question, RE: superheated wet steam?

    Homework Statement A gas fired superheater takes wet steam at a pressure of 40 bar and a dryness fraction of 0.95 and heats it isobarically such that it leaves at 380c. Assuming no losses occur, sketch the process on a ts diagram and determine; i)the rise in specific entropy through the...
  29. K

    Erossion in air to steam heat exchanger

    We have this heat exchanger installed in our plant. There are two modules. In module-2 saturated steam is entering @200 Deg C and heating the air from 40 to 80 Deg C. Condensate from module-2 is given to module-1 which preheats the air entering in module-2 from ambient temp (30 Deg C) by 10 Deg...
  30. M

    How Much Heat To Turn Water To Steam?

    How much heat must be added to 120g of water at an initial temperature of 60C to heat it to the boiling point? completely convert the 100C water to steam? Specific heat capacity of water = 1.0cal/g-C It would take 120*1 to raise 120g of water up to 1C difference in temperature = 100C -...
  31. R

    Calorimetry homework: mixing steam and liquid water

    Homework Statement What mass of steam at 100 degree celsius must be passed into 5.4 kg of water at 30 degree celsius to raise temperature of water to 80 degree celsius? Homework Equations C(water)=4.2 J/(g C) L(steam)=2268 J/g The Attempt at a Solution Assuming no heat loss...
  32. P

    Flywheel of a steam engine problem

    Homework Statement The flywheel of a steam engine runs with a constant angular speed of 156rev/min. When the steam is shut off, the friction of the bearings and of the air brings the wheel to rest in 2.20h. What is the tangential linear acceleration of a particle 52.4cm from the axis of...
  33. C

    Finding h2 Using Steam Tables and Enthalpy Equations

    Hello again...i was wondering if you can help? I am using enthalpy equations to try and find h1 and h2 to work out 'work and heat transfers' for water, for a piston type question. I have calculated work done using: [w = -PDV] To find the heat transfer i need to use: [Q=m.(h2-h1)] i...
  34. Arctic Fox

    Any such thing as small steam turbine ?

    Any such thing as "small steam turbine"? I've a C-Band satellite dish. I'm going to attach 2" mirrors to the entire reflecting surface and aim it at the sun. Where the feedhorn was, I'm going to design some type of coil to pump water through which the focused sunlight will boil the water...
  35. S

    Steam Power Plant: Solve Home Work Task

    Hi guys been given the following as some home work, haven't got a clue really its a bit confusing! Steam ar 40 bar and 400C enters the high pressure turbine of a steam power plant at a rate of 20kg/s and explands to a pressure of 3 bar at which point it is just dry saturated. at this point...
  36. S

    Efficiency Analysis of a Steam Power Plant with Reheat and Feed Heater

    Hi guys, very similar to my other thread apart from this is work from Thermofluids 2! Steam ar 40 bar and 400C enters the high pressure turbine of a steam power plant at a rate of 20kg/s and explands to a pressure of 3 bar at which point it is just dry saturated. at this point part of the...
  37. K

    The Science Behind Steam Ejectors for Vacuum Creation

    Mmmmm... why only steam is used in a steam ejector for creating vacuum and not anything like air or other inert gases...:confused:
  38. K

    Steam reformer vs dry reformer

    Which one would you prefer? Steam reformer: CH4 + H2O -> CO + 3H2 CO + H2O -> CO2 + H2 Dry reformer: CH4 + CO2 -> 2CO + 2H2 1) The SR uses steam injection, the DR doesn't have steam, which can be good. 2) The DR doesn't yield much H2 for a given amount of CH4... And the...
  39. V

    Calculating Tangential Acceleration of a Particle on a Flywheel

    Homework Statement The flywheel of a steam engine runs with a constant angular speed of 137 rev/min. When steam is shut off, the friction of the bearings and the air brings the wheel to rest in 2.7 h. What is the magnitude of the tangential component of the linear acceleration of a...
  40. F

    Rotational motion- steam engine

    Homework Statement The flywheel of a steam engine begins to rotate from rest with a constant angular acceleration of 1.35 rad/s^2. It accelerates for 33.1 s, then maintains a constant angular velocity. Calculate the total angle through which the wheel has turned 47.5 s after it begins...
  41. V

    Mixing ice, steam, and water and find equilibrium

    Homework Statement .15 kg of steam at 100 degree Celcius is mixed with .2kg of water at 50 degree and .2 kg of ice at 0 degree. Determine the final temperature and phase(s) of the final state. Assume that no energy is lost to the surroundings. Homework Equations The Attempt at a...
  42. J

    Thermopile, let extract some electricity from heat without steam

    I want to build a Thermopile to generate usable electricity with a heat source, like a small fire or something, I can build something like this but, I only get 1 mA and an ant of a volt. And it subjected to 1700C blow torch, it sucks. So does anyone have some info about that, would be nice...
  43. A

    How Much Energy Is Required to Convert Ice at -13°C to Steam at 113°C?

    Given: cp, ice = 2090 J/ kg . Celsius cp, water = 4186 J/ kg . Celsius cp, steam = 2010 J/ kg . Celsius Lf = 3.33 x 10 ^5 J/ kg Lf = 2.26 x 10 ^6 J/ kg How much energy is required to change a 38g ice cube from ice at -13 degrees C to steam at 113 degrees C? Answer in units of J. I...
  44. sas3

    Microwave Steam Engine, Would this work?

    I found this the other day and was wondering if it could work. If nothing else it is an interesting concept. http://www.keelynet.com/energy/microeng.htm"
  45. H

    Water to Steam Energy Question

    Homework Statement How much energy does it take to transform 500 g (0.5kg) of liquid water at 20 oC to steam at 100 oC? Note that the specific heat capacity of liquid water is 4.28x10^3 J/Kg/oC and the latent heat of vaporization for water is 2.3x10^6 J/Kg. Homework Equations Eh=mct ...
  46. J

    Torque difference: steam turbine vs. piston?

    Hi, I was told that there was an inherent torque advantage to using a piston design over a turbine design (in this case for steam). I said I doubted there was any theoretical reason why this would be true, it would all depend on the design of the engine. My argument was that most turbines in...
  47. P

    How Much Energy is Needed to Transform Ice into Water and Steam?

    A 55 g ice cube at 0°C is heated until 40 g has become water at 100°C and 15 g has become steam at 100°C. How much energy was added to accomplish the transformation? I tried using Q=mL for each change and adding them together. Q=.055(3.33x10^5) Q=18315 then Q=.015(2.26x10^6)...
  48. C

    To turn 50g of boiling water to steam requires

    Please someone help me with my homework :D i have tried and tried but i just suck at science 1. To turn 50g of boiling water to steam requires A. 50 Calories (210 Joules) B. 500 Calories (2100 Joules) C. 540 Calories (2270 Joules) 2. If you were caught freezing in cold weather...
  49. J

    Calculating Mass Flow Rate of Steam Turbine

    Steam enters a turbine at 3 mpa and 450 c, expands in a reversible adaibatic process, (KE and PE are negligible) and exhausts at 10 kpa. The power output of the turbine is 800 kW. What is the mass flow rate? I did the problem but I don't know if the anwser is correct and wanted to check...
  50. O

    Can a Car Airconditioning Compressor be Used as a Pico Steam Turbine?

    Hi All, I am a solar thermal enthusiast seeking to try out a few things. I need some info on using car aircondition compressor as a pico steam turbine if it is possible. Links, suggestions and opinions are welcome. Regards, Solomon.
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