Author: haroonkhan
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Actual Indicator Diagram
Actual indicator diagram is shown in Figure 5.5. In this diagram, points 1, 2, 3, 4 and 5 show actual admission pressure, point of cut-off, point of release, point of closing the exhaust port and starting of compression, and point of opening of admission port, respectively. The area of actual indicator diagram is less than the…
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Modified Rankine Cycle: Theoretical Indicator Diagram
Theoretical indicator diagram for a steam engine is shown in Figure 5.3 without clearance volume and with clearance volume in Figure 5.4. In Figure 5.3, clearance volume is zero. Steam at boiler pressure enters into the cylinder at point 1 and cut-off at point 2. Then the steam expands inside the cylinder isothermally from point 2 to point 3. Point 3…
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STEAM ENGINES AND THEIR WORKING PRINCIPLES
A steam engine is a reciprocating heat engine that performs mechanical work by using steam as its working fluid. Steam engines are external combustion engines based on modified Rankine cycle, where the working fluid is separate from the combustion products. Water is heated in a boiler until it reaches a high pressure and temperature (superheated…
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INTRODUCTION TO STEAM POWER SYSTEMS
Steam power system is a system in which the heat energy of the steam is used to produce mechanical power. Various types of fuels (coal, diesel, natural gas, geothermal, nuclear, etc.) are used to produce the high quality of steam, i.e., superheated steam and then the thermodynamic expansion process is used to convert the heat…
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PERFORMANCE OF BOILERS
Evaporation Rate: It is steam generation rate of boilers which may be expressed in terms of kg of steam per unit heating surface area or kg of steam per cubic metre of furnace volume or kg of steam per kg fuel burnt. Equivalent Evaporation: It is equivalent of evaporation of 1 kg of water at 100°C to…
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Chimney Height and Cross-sectional Area
Chimney Height: where h is draught in mm of water, H is chimney height in metre, Ta is temperature of outside air in Kelvin, Tf is flue gas temperature in kelvin, m is mass of air supplied per kg of fuel in kg. If Hf is height of hot gas column in metre Mass Flow Rate of Hot Flue Gas: Condition for Maximum Discharge: Example 4.12: Calculate minimum…
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CHIMNEY HEIGHT CALCULATION
Draught Draught is a small pressure difference causing flow of flue gas and air through the boilers. It is necessary for efficient combustion and to release the gases at sufficient height to avoid local pollution. There are mainly three types of draughts—induced draught, force draught, and natural draught. Natural draught is pressure difference of hot…
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Pressure Reducing Valve
The function of pressure reducing valve is to maintain constant pressure on its delivery side of the valve irrespective of fluctuating demand of steam. This is achieved by throttling of steam passing through the pressure reducing valve. It is generally used in low capacity boilers where it is difficult to maintain constant delivery pressure with…
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Steam Separator
The function of a steam separator is to separate the suspended water particles carried by steam on its way from the boiler to the engine of turbine. It is installed in the main stream pipe very near to engine. The constructional details are shown in Figure 4.28. Figure 4.28 Steam Separator The steam from boiler enters the…
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Steam Trap
The function of steam trap is to drain the water condensed due to partial condensation and jacket without allowing the steam to escape through it.