![]() Liquids - Latent Heat of Evaporation - Latent heat of vaporization for fluids like alcohol, ether, nitrogen, water and more.Latent Heat Flow - Latent heat is the heat when supplied to or removed from air results in a change in moisture content - the temperature of the air is not changed.Heating Water by Injecting Steam - Water can be heated by injecting steam.Evaporative Cooling - Evaporative cooling tutorial.Energy Accumulated in Heated Water - kWh - The amount of thermal energy stored in heated water.Condensation of Steam - Heat Transfer - Heat transfer when steam condensates.Thermodynamics - Thermodynamics of steam and condensate systems.Gases and Compressed Air - Air, LNG, LPG and other common gas properties, pipeline capacities, sizing of relief valves.Be aware that c ps varies with temperature. T s = superheated steam temperature ( oC)Ĭ ps = 1.860 (kJ/kg oC) at standard atmosphere. H s = enthalpy of superheated steam (kJ/kg)Ĭ ps = specific heat of steam at constant pressure = 1.860 (kJ/kg oC) The specific enthalpy of superheated steam can be calculated from: The energy to evaporate 5 kg of water at atmospheric pressure can be calculated as The energy to evaporate a certain amount of water can be calculated as = 2257 (kJ/kg) Example - Energy to Evaporate Water Specific evaporation enthalpy for water at standard atmosphere is: H e = specific evaporation enthalpy (kJ/kg) The specific enthalpy of evaporation can be calculated from: The value depends on the pressure.įor saturated steam at standard atmosphere - 2) - the specific enthalpy - h g - is 2676 kJ/kg. Specific enthalpy of saturated steam - h g - can be obtained from tables as above. T 0 = refer temperature = 0 ( oC) Specific Enthalpy of Saturated Steam The specific enthalpy of water (in SI units) can be calculated from:Ĭ w = specific heat water (4.19 kJ/kg. At standard atmosphere - 1 bar (14.7 psi) - water starts boiling at 100 oC (212 oF). The value depends on the pressure.įor saturated water at standard atmosphere - 2) -the specific enthalpy - h f - is 419 kJ/kg. Specific enthalpy of saturated water - h f - can be obtained from tables as above. For pressures above the critical point there is no definite transition from liquid to vapor. 2) referrer to water boiling at standard atmosphere.v f - change very little and is also often omitted. Internal energy - u - can be calculated from (2) and is often omitted in tables. suffix - g - referrer to saturated vapor - steam.suffix - f - referrer to saturated liquid.Part of the water vapor - steam - properties can be expressed in a table as:įor full table with Enthalpy and Entropy - rotate the screen! Specific enthalpy is a property of the fluid and can be expressed as: H = specific enthalpy (kJ/kg) Specific Enthalpy ![]() EnthalpyĮnthalpy of a system is defined as the mass of the system - m - multiplied by the specific enthalpy - h - of the system and can be expressed as: The most common vapor is evaporated water - steam or moist. The heat required for changing state as evaporation is referred to as latent heat of evaporation. The heat transferred to a substance when temperature changes is often referred to as sensible heat. the vapor heats above the evaporation temperature - super-heating.the liquid evaporate at the evaporation temperature by changing state from fluid to gas.the liquid heats up to the evaporation temperature.When a liquid evaporates its go through a process where
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