Expansion of steam

The theoretical values for enthalpy may be read from a Mollier chart, where hj is the enthalpy of the steam at the turbine inlet, and hg is the enthalpy of the steam at the exhaust pressure and at the inlet entropy. The expansion of steam through the turbine is theoretically at constant entropy. These theoretical rates must be corrected for performance inefficiencies of the particular turbine. The calculations presented here are good for the average design, but exact values for a particular make and model turbine must be quoted by... 

A turbine design where the expansion of steam occurs entirely in fixed nozzles. The steam jets from the nozzles are directed into disc-mounted buckets on the rotor forcing the shaft to rotate. 

Turbines utilize the expansion of steam or a gas to deliver power to a rotating shaft. Salient features of such equipment are... 

Isentropic expansion of steam from the initial conditions to this pressure results in a slightly superheated vapor, for which by double interpolation in Table F.2 ... 

Consider the first section of the turbine and the first feedwater heater, as shown by Fig. 8.6. The enthalpy and entropy of the steam entering the turbine are found from the tables for superheated steam. The assumption of isentropic expansion of steam in section I of the turbine to 2,900 kPa leads to the result ... 

Now consider a steam turbine as shown by the methods in Chap. 8, the reversible, adiabatic expansion of steam through a nozzle from about lOOpsia to atmospheric pressure produces a flow with a velocity of about 3000 ft/s. Thus, the blade desirable to use a... 

Explosions of Pressure Vessels Containing Non-reactive Materials This type of explosion has similarities to a BLEVE. It is typical for a pressure vessel with a weak structure that will fail at quite low pressures (less than 2 lb/ in. (gauge)). Materials are not thrown as violently as in a BLEVE. The pressure vessel itself may have severe damage from the rapid expansion of steam or from a combustion explosion within the vessel. 

Calculate the fraction of the enthalpy of vaporization of water used for the expansion of steam at its standard hoiling point. 

V Expansion of steam in a turbine Fuel oil fuel gas burning... 

Isoenthalpic An expansion of steam that does not convert heat to velocity. An irreversible process. 

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