steam power.pdf

8/10/2019 Steam Power.pdf

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SISTEM TENAGA UAP

SIKLUS RANKINEPrinsip Kerja dan Perpindahan PanasAsumsi:1. Perpindahan Panas antara sistem ke lingkungan

diabaikan.2. Energi Kinetik dan Energi Potensial diabaikan.3. Setiap komponen beroperasi pada steady state.4. Penggunaan persamaan-persamaan konversi massa dan

energi.


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Open Vapor Power Cycle: Rankine Carnot CycleDescription: A concept implementation of the Carnot cycle through Rankine cycle. Heat additionand rejection take place at constant temperatures. Practical difficulties arise from the fact that

turbines cannot handle wet vapor well and pumps, designed to handle liquid, cannot handle two

phase mixture well. For analyzing a Rankine cycle use the daemons (thermodynamic calculators)located in the following page: TEST.Daemons.Systems. Open. SteadyState. Specific. PowerCycle.


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Open Vapor Power Cycle: Basic Rankine CycleDescription: The work required by the pump to raise the pressure of a liquid (integral vdp) is much less thanthe work produced by the turbine as vapor(integral vdp) has a much greater specific volume than liquid. Thecooling tower is not necessary in areas where the cooling water can be drawn from natural reservoirs such as

river, lake, or ocean. For analyzing a Rankine cycle use the daemons (thermodynamic calculators) located in thefollowing page: TEST.Daemons.Systems. Open. SteadyState. Specific. PowerCycle.


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Open Vapor Power Cycle: Real Rankine CycleDescription: A real cycle deviates from an ideal Rankine cycle in several ways: the pump and the

turbine are not isentropic, there can be pressure losses in the connecting pipes, boiler, andcondenser, and there can be heat losses from the turbine and the pipes carrying superheated

steam. For analyzing a Rankine cycle use the daemons (thermodynamic calculators) located in thefollowing page: TEST.Daemons.Systems. Open. SteadyState. Specific. PowerCycle.


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Open Vapor Power Cycle: Basic Rankine CycleDescription: The work required by the pump to raise the pressure of a liquid (integral vdp) is much less thanthe work produced by the turbine as vapor(integral vdp) has a much greater specific volume than liquid. Thecooling tower is not necessary in areas where the cooling water can be drawn from natural reservoirs such as

river, lake, or ocean. For analyzing a Rankine cycle use the daemons (thermodynamic calculators) located in thefollowing page: TEST.Daemons.Systems. Open. SteadyState. Specific. PowerCycle.


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Rankine Cycle: ReheatDescription: Reheating the steam coming out of the high pressure turbine raises the effectivetemperature of heat addition and, hence, the thermal efficiency. It also raises the quality of

steam at the exit of the low pressure turbine. For analyzing any modified Rankine cycle use thedaemons (thermodynamic calculators) located in the following page: TEST.Daemons.Systems.

Open. SteadyState. Specific. PowerCycle.


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Rankine Cycle: Regeneration with Closed and Open FWHDescription: Steam bled from the turbine exchanges heat with the condensate returning from the condenser.

Although closed FWH is more expensive and less efficient, each additional closed FWH does not require aseparate pump unlike the open FWH. Although a pump is used in this particular configuration the bleed could

be throttled down to the pressure of the condenser. For analyzing any modified Rankine cycle use the

daemons (thermodynamic calculators) located in the following page: TEST.Daemons.Systems. Open.SteadyState. Specific. PowerCycle.


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Rankine Cycle: Cogeneration - Producing Power and Supplying Process SteamDescription: Process steam is bled from the turbine as well as obtained directly from the supply

line to the turbine, depending on the load. An expansion valve is necessary to reduce thepressure (at constant enthalpy) when the turbine is bypassed. For analyzing any modified Rankine

cycle use the daemons (thermodynamic calculators) located in the following page:TEST.Daemons.Systems. Open. SteadyState. Specific. PowerCycle.


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Open Power Cycle: Combined gas and Vapor CycleDescription: The combined cycle achieves a higher thermal efficiency compared to either of the

constituent cycle by combining the high effective temperature of heat addition of a Brayton cyclewith the low effective temperature of heat rejection of a Rankine cycle. For analyzing any

modified Rankine cycle use the daemons (thermodynamic calculators) located in the followingpage: TEST.Daemons.Systems. Open. SteadyState. Specific. PowerCycle.


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Open Vapor Power Cycle: Rankine Carnot CycleDescription: A concept implementation of the Carnot cycle through Rankine cycle. Heat additionand rejection take place at constant temperatures. Practical difficulties arise from the fact that

turbines cannot handle wet vapor well and pumps, designed to handle liquid, cannot handle twophase mixture well. For analyzing a Rankine cycle use the daemons (thermodynamic calculators)located in the following page: TEST.Daemons.Systems. Open. SteadyState. Specific. PowerCycle.


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Open Refrigeration Cycle: Refrigerator as a Closed Steady SystemDescription: A household refrigerator, operating at steady state, maintains the cold space cold by

removing heat at the same rate as it leaks through the seals and other imperfect insulations.Note that an overall analysis can be performed by treating the refrigerator as a closed steady

system.

steam power.pdf

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