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. askingask

    Vacuum by condensation causes water to boil?

    So basically if I have a closed container with a valve, and inside the container there is water. Now i heat the container and boil the water. The valve is open so steam escapes form there. I now close the valve and cool the container causing the steam to condense inside. Inside the container is...
  2. sandvoxel

    I Simulating a 2-Phase Water System: Tips and Resources for Dynamic Simulation

    I am currently trying to simulate a boiler using the IAPWS-IF97 model of water states. I have looked into the equations but I always seem to run into a condition where I need 2 states at once that depend on one another. I was wondering if anyone had some good learning resources on simulating a 2...
  3. S P

    As much steam as possible from engine exhaust gas + warm water?

    Hi all, The idea is to generate as much as possible water steam from heat of internal combustion engine exhaust gas. The so called steam generation device is a simple sloped engine exhaust pipe where water from engine cooling and hot gas is fed at the top and all the mix is exiting at the...
  4. AhmedAB

    I have a problem finding a steam table for n-pentane

    hey, I was searching for a steam table for a long time but I wasn't lucky, I don't know why an n-pentane, iso-pentane or even pentane table is hard to find , so I am here today asking for a steam table for n-pentane or pentane table, forgive me if I was asking too much, Thank you very much you all.
  5. jesmitter

    Thermodynamics Question About Steam

    How long does it take for 500 degree F - 1000 psi steam to move through 24" of 3/16 ID pipe and fill a 1 cubic inch volume cylinder to 1000 psi? Can it be modeled mathematically or with the help of Steam Tables?
  6. Nick Goodson

    Figuring Out Heat Transfer & Entropy of Steam at 10 MPa

    Hello everybody, would somebody please put me on the right track to answering this question? 'Consider water undergoes a heat transfer at constant pressure of 10 MPa and changes from liquid to steam. Find the entropy of the system (sfg) as well as the heat transfer per unit mass in this...
  7. J

    Working out steam velocity with only pressure difference

    I am currently doing an assignment on nuclear power and in the turbine, the steam is moving from pressure of 6Mpa to 0.008 Mpa. is there any way to work out the velocity of the steam when moving between these pressure differences?
  8. D

    I Steam flow rate in 2-chamber steam engine system

    Our system of interest has a duct on the left and a piston chamber on the right that make the shape of the letter T rotated 90º clockwise. The smaller tube on the left is abbreviated as P1 has an unspecified length while the piston chamber is P2. The air in P2 heats up and expands while the...
  9. E

    Here is a 3D model I made of a large industrial steam turbine

    This is a 3D model I made of a large industrial steam turbine. It was modeled after one of the turbines at the Port Richmond generating station in Philadelphia Pennsylvania. I plan on modeling the entire turbine hall of that power plant, but that will take several months, at least. The program...
  10. PaxFinnica96

    Engineering Steam Turbine with Open Regenerative Feed Heater

    I would very much appreciate anyone to cast their eye over my attempt at solving this problem which I've been struggling with the past few days. Many thanks in advance. Assuming that: energy input from open-type regenerative feed heater pump is negligible no energy is lost the heater pressure...
  11. Will26040

    How do I get the Convection Coefficient for steam in a jacketed vessel?

    Please could someone point me in the direction of an equation/ book I can use to obtain the convection coefficient for steam in a heating jacket. Steam is at 1 bar pressure. I think I need to use a dimensionless number. Thanks
  12. lenilein

    Massflow of steam to be supplied to a drying cylinder

    Good afternoon, I am trying to calculate the massflow of steam required in a cylinder used for paper drying but I think there is a bug in my calculation and I would love to get your help to find where the issue is! Saturated steam is continuously supplied to a cylinder. The steam condenses in...
  13. S

    Calculate energy required to heat water using a steam coil

    I'm trying to complete this past exam paper Q. Water volume = 200hl = 20000L 1L=10^-3 m^3 20000L = 200 m^3 Density of water at 15 deg C = 999 kg m^3 Density = Mass/Volume 999 kg m^3 = Mass/(200 m^3) Mass of water = (200)(999) = 199800 kg Heat required to to heat 199800 kg water: Q =m C dT =...
  14. seeker11

    Steam Speed from a Heat Ruptured 120 Gallon Water Tank?

    PROBLEM: A 120 gallon tank (26" diameter, 60" height) containing 40 Gallons of water is heated up until the tank ruptures from overpressure at 125 PSI (maximum tank rating). How to calculate the initial escaped steam velocity at the ruptured tank, assuming the gash is 2 feet long in the...
  15. S

    Steam boiler efficiency calculations

    Summary:: I'm going through my homework. I am confident I have everything correct except for my boiler efficiency. It seems too high at 99%. I would like to think my logic is sound but it can't be right. A boiler is designed to generate steam at 5 MPa and 400oC. A fuel is selected with a...
  16. Twigg

    Kelvin-Planck 2nd Law of Thermo & a Syringe Steam Engine

    So I found this steam engine on the youtubes: Consider the system not including the candles, only including the can that makes up the boiler shell and the piston, flywheel, etc. The boiler can acts as a hot reservoir; however, the Kelvin-Planck statement of the 2nd law says you can't have an...
  17. K

    Will steam generated inside an oven not break it?

    Disclaimer first: Though the question is around cooking, IMO it certainly is to with physics / engineering. Yet, if the admins find this post inappropriate, pl. delete it. I am planning to make some rice cakes which is prepared by steaming a mix of rice powder and water. Because I don't have...
  18. S

    History History of Steam Plants: USA Heyday & Accidents

    The term "Steam plant" can refer to a place that distributes steam for heating buildings - as opposed to a plant that generates electricity. I have the impression that there are few, if any, such steam plants in operation in the USA. When was their heyday? Were there accidents from broken...
  19. Yeahaight

    Steam = 100C -- how much steam got injected into the water to heat it up?

    I guess, firstly I have to calculate the heat that is needed. Q=c*m(t2-t1) I'm not sure what to do further from here.
  20. S

    Calculate the flow of steam to heat wort (in the brewing process)

    I need help solving this please. Its a past exam paper. requires wort to undergo 5% by mass evaporation in one hour does this mean starting vol is 500hl and after one hour vol should be 475hl Wort volume = 500 hl = 50,000 L / hr 1 L = 10^-3 m^3 50,000 L = 50 m^3 /hr = 0.833 m^3 / min = 0.01388...
  21. S

    Calculate the Mass of Steam / Enthelpy

    Detergent: Volume = 20hl = 2000L 1L = 10^-3 m3 2000L = 2m3 Density: 1020 kgm-3 Mass Detergent: (2)(1020) = 2040 kg Detergent heat gain = (2040)(4.13)(80-10) = 589,764 kJ Detergent heat gain = steam heat loss 589,764 = m(2738-603)(100-0) Mass Steam = 2.76 kg 95% effeciency = 2.91 kg The...
  22. S

    Steam Flow through holes in a pipe

    What will be mass flow rate of dry saturated steam through holes on a pipe. Pipe ID: 25mm, Steam Pressure 3 kg/cm^2, Holes' Dia: 3mm, Number of Holes: 5.
  23. B

    Could steam cars be possible in the 2020s?

    I was wondering if electric could be use to boil the water to power a steam car for modern use ?? Also why haven't steam cars being developed more for the 2020's?
  24. chemisthypnos

    How much steam is produced in an electric arc furnace?

    Hello, everyone. Does anyone know how much steam is produced by an electric arc furnace in a set amount of time? I have not been able to find any information on this despite how much water is no doubt used to cool the electric arc furnace. Can anyone help?
  25. E

    Internal energy of a container filled with water & steam

    I've worked out that half of the steam must condense (since the pressure of the steam needs to remain constant for the forces on the massless piston to balance). Also, if the total volume of the container is ##V##, the work done on the system equals ##\frac{P_{atm}V}{4}##. When half of the steam...
  26. S

    What is the Formula for Calculating Enthalpic Capacity in Steam Heat Transfer?

    I) Area = 3.14 x L xD 3.14 x 60 x 0.11 = 20.72m2 Q=UADT = (1.0Wm2k-1)(20.72m2)(150-20) = 2693.6 W Changed flow rate from 0.1kgs-1 to 360kghr-1 II) Enthalpic Capacity in dry steam = steam flow rate x latent heat vaporisation Q=mDh = 360 x 2114 (formula looks for lat heat vap but we have latent...
  27. E

    3D model I created of the largest steam locomotive ever built

    Here is a 3D model (blender 2.8) I created of the Chesapeake And Ohio Allegheny 1601 steam locomotive, which remains today the largest locomotive ever built.
  28. tinakaran26

    Direct steam injection into cooling water line at pump suction

    Currently there is an operation scenario at one of our plant which directly injecting steam into cooling water line at pump suction in order to generate hot water at 60 deg C for circulation, by doing this its generate vapor at pump suction and lead to cavitation which ultimately damage pump and...
  29. Izazo

    Calculating Steam Turbine output power

    So I know the formula " W_turbine = m_flow rate * (H_in - H_out) " BUT is there any formula that utilizes the turbine volumetric flow rate (m^3/sec) at the outlet? The following data is available, I just need the formula... P_in= 2.36 Mpa P_out= 0.95 MPa m_flow rate= 0.02 kg/sec eff_turbine= 70...
  30. Izazo

    Outlet Volume flow rate from a steam turbine

    I am working Organic Rankine Cycle. I studied a number of research papers and in most of them, they have calculated outlet volume flow rate from the turbine or expander, but have not mentioned the calculations. So here are the available data; Pin = Turbine Inlet Pressure, 2.5 MPa Pout = Turbine...
  31. T

    Flow rate of steam in power plants

    I want to know what's the flow rate (in kg/s) of saturated steam at 5 barA pressure to the turbines of a 250 kW power plant.
  32. S

    Calculating Centripetal Acceleration of a Locomotive's Crank Pin

    Problem Statement: A locomotive is running at a constant speed of 100 km / h. The diameter of driving wheels is 1.8 m. The stroke of the piston of the steam engine cylinder of the locomotive is 600 mm. Find the centripetal acceleration of the crank pin relative to the engine frame. Relevant...
  33. Chandrakanth_balusa

    Question about the Ramping-up procedure for a steam boiler

    Hello Experts, I have a question regarding the operation of a steam boiler. if the load is increased on the turbine generator set of a steam power plant, i learned that the fuel injection to the boiler has to be increased to serve the additional load. so my question is, do we also have to...
  34. S

    Automotive Design of a Valve stem cross section in a Steam turbine emergency valve

    I want to design cross section area required for valve stem when valve is closed under spring force. Valve stem should be designed for buckling load but I am unable to calculate buckling load coming due to impact force coming when valve bangs on valve seat. Valve is having concentric spring. Is...
  35. L

    Steam Engine Questions: Confederate Torpedo Boats and Operation in the 1860s

    Were steam pressure gauges used in 1860? Was a vessel reversed by reversing the engine or within the gearing? For a small steam powered launch, how long from a dead stop would it take to get a boiler up to operating steam? This is for my study of Confederate torpedo boats. Thank you for your...
  36. Chandrakanth_balusa

    How does the pressure in a steam header react to a sudden load change?

    Hello People, I have querry regarding the pressure variation in the steam header in the steam power plant. if there is a sudden change in the load and the mass flow through the turbine has to be increased, i would like to know how it effects the pressure value? if yes how does this change...
  37. Chandrakanth_balusa

    How to estimate the time it takes to generate steam?

    Hello people, I have a question regarding the time calculation. could you please let me know if there are any equations with which I can find the time to generate steam in the header for certain pressure level. lets say I am supplying fuel and mass flow of water to the boiler at certain...
  38. Chandrakanth_balusa

    Estimation of the Power Output of a steam turbine

    Hoow can one estimate the amount of steam required to generate certain amount of electical power mathematicaly?
  39. TheBigDig

    Efficiency of a steam power plant

    My inital assumption was to just take T1 = 5600 and T2= 300K, find the maximum efficiency and then divide it by two and three but I don't believe this question to be that simple. I'm confused as to where the 750K fits in as I thought no matter what occurred in between the heat reservoir and heat...
  40. J

    Steam turbine start-up degree of superheat

    Trying to find more information on steam quality requirements on a start up of a 70's vintage GE turbine ( impulse type 2 casings compound double flows reheat condensing turbine). I've read in detail manufacturers recommendations regarding rate of metal temperature change in the 1st stage and...
  41. P

    What is the most efficient way to create steam with the desired properties?

    Hello! new here. recently I've developed an interest in the way electricity is produced, I've seen some mechanisms, most of them are steam turbine based. i have a few questions about the topic, mainly about thermodynamics. if i want to create enough energy to move a steam turbine that requires...
  42. C

    B Could steam be expanded through a nozzle to get 0°C gas?

    Obviously expanding the gas cools it down. I'm interested if you could boil water and then expand the high pressure steam to cool it down to 0°C. Or are there subtler thermodynamics that would prevent this?
  43. EastWindBreaks

    Are theses approaches correct? (entropy change of water turning into steam)

    Homework Statement An insulated piston-cylinder device contains 5 L of saturated liquid water at a constant pressure of 150 kPa. An electric resistance heater inside the cylinder is now turned on, and 2200 kJ of energy is transferred to the steam. Determine the entropy change of the water...
  44. S

    Chernobyl and steam explosions

    Hello I must do a report on Chernobyl: before, during and after. I have all I need except for a clear and simple explanation of how steam explosions work in this regard. All the online sites I've been on provide information that is too advanced, and as a non native English speaker, the...
  45. Paul Lasdivan

    Steam Turbine: Solve for Velocity

    Homework Statement Homework Statement [/B] A steam turbine developed 2372.20 Hp when its inlet condition is 1300 Btu/lb enthalpy and 400 ft/s velocity and steam flow of 200 Btu/min :The exit enthalpy is 800 Btu/min. Find the exit velocity. That is the original problem statement but i think the...
  46. J

    Power generated by the steam turbine

    Homework Statement Shown in the figure Homework Equations W= (p2v2-p1v1) / (1-n) The Attempt at a Solution I am not sure where to start and where to use all the data given in the table. Please help. It would be nice if someone could explain the basic nature of the steam turbine, how it...
  47. J

    Power generated by the steam turbine

    Hello, I'm trying to solve a question, please help me.
  48. T

    Water / steam homogeneous mixture

    We all here (I presume that members here have better understanding of physical processes than average person) know that it isn't a fact that water began to boil at 100°C but much before that. When being heated in an open pot, as the temperature rises, water began to boil and more and more water...