6 min read•Last Updated on July 30, 2024
Combined gas-vapor power cycles blend gas and steam turbines for maximum efficiency. By using waste heat from gas turbines to generate steam, these systems achieve higher power outputs and lower fuel consumption than standalone cycles.
These hybrid systems offer numerous benefits, including improved thermal efficiency, reduced emissions, and operational flexibility. Understanding the principles behind combined cycles is crucial for optimizing power generation and meeting evolving energy demands.
Process Simulation of a 620 Mw-Natural Gas Combined Cycle Power Plant with Optimum Flue Gas ... View original
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Process Simulation of a 620 Mw-Natural Gas Combined Cycle Power Plant with Optimum Flue Gas ... View original
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Process Simulation of a 620 Mw-Natural Gas Combined Cycle Power Plant with Optimum Flue Gas ... View original
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Process Simulation of a 620 Mw-Natural Gas Combined Cycle Power Plant with Optimum Flue Gas ... View original
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Process Simulation of a 620 Mw-Natural Gas Combined Cycle Power Plant with Optimum Flue Gas ... View original
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Process Simulation of a 620 Mw-Natural Gas Combined Cycle Power Plant with Optimum Flue Gas ... View original
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Process Simulation of a 620 Mw-Natural Gas Combined Cycle Power Plant with Optimum Flue Gas ... View original
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Process Simulation of a 620 Mw-Natural Gas Combined Cycle Power Plant with Optimum Flue Gas ... View original
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Process Simulation of a 620 Mw-Natural Gas Combined Cycle Power Plant with Optimum Flue Gas ... View original
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Process Simulation of a 620 Mw-Natural Gas Combined Cycle Power Plant with Optimum Flue Gas ... View original
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A boiler is a device used to generate steam or hot water by transferring heat from a fuel source to water. It plays a crucial role in various thermodynamic cycles, especially in converting thermal energy into mechanical energy. The efficiency and design of the boiler significantly affect the overall performance of systems like steam power plants and combined gas-vapor cycles.
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A boiler is a device used to generate steam or hot water by transferring heat from a fuel source to water. It plays a crucial role in various thermodynamic cycles, especially in converting thermal energy into mechanical energy. The efficiency and design of the boiler significantly affect the overall performance of systems like steam power plants and combined gas-vapor cycles.
Term 1 of 27
Thermal efficiency is a measure of how well an energy conversion system, such as a heat engine, converts heat energy into useful work. It is defined as the ratio of the useful work output to the heat input, typically expressed as a percentage. This concept is crucial for evaluating and optimizing the performance of various thermodynamic cycles and systems.
Heat engine: A device that converts thermal energy into mechanical work by operating between two heat reservoirs.
Carnot cycle: An idealized thermodynamic cycle that provides the maximum possible efficiency a heat engine can achieve, based on reversible processes.
Second-law efficiency: A measure of how effectively a system utilizes available energy relative to the maximum possible efficiency determined by the second law of thermodynamics.
A turbine is a mechanical device that converts fluid energy into mechanical work, typically by rotating blades driven by a flowing fluid such as water, steam, or gas. This conversion is crucial for various applications, particularly in energy generation and propulsion systems, where turbines play a significant role in harnessing energy from different sources.
Compressor: A device that increases the pressure of a gas by reducing its volume, often used in conjunction with turbines in gas power cycles.
Heat Exchanger: A system designed to transfer heat between two or more fluids without mixing them, commonly used in conjunction with turbines to enhance energy efficiency.
Generator: A machine that converts mechanical energy from a turbine into electrical energy, commonly found in power plants.
A heat recovery steam generator (HRSG) is a type of heat exchanger that captures exhaust heat from gas turbines or other sources and uses it to produce steam. This steam can then be utilized for power generation or other processes, significantly improving the overall efficiency of combined gas-vapor power cycles by reusing waste heat.
Combined Cycle Power Plant: A power plant that utilizes both gas and steam turbines to generate electricity, maximizing efficiency by recovering waste heat from the gas turbine.
Thermal Efficiency: The ratio of useful work output to the heat input, often expressed as a percentage, indicating how well a system converts heat energy into work.
Exhaust Heat Recovery: The process of capturing waste heat from industrial processes or engines to be reused in heating applications or power generation.
A condenser is a heat exchanger used to condense vapor into liquid by removing heat from the vapor, usually through contact with a cooler surface or fluid. This process is crucial in various thermodynamic cycles and systems, enabling efficient heat transfer and phase change essential for energy conversion, refrigeration, and air conditioning.
Heat Exchanger: A device that facilitates the transfer of heat between two or more fluids without mixing them, commonly used in condensers and other thermal systems.
Phase Change: The transition of a substance from one state of matter to another, such as from gas to liquid in the condensation process.
Cooling Tower: An evaporative cooling system that removes waste heat from industrial processes or HVAC systems, often working in conjunction with condensers.
The Brayton Cycle is a thermodynamic cycle that describes the functioning of a gas turbine engine, where air is compressed, mixed with fuel, and then combusted to produce work. This cycle is significant for understanding how heat engines convert thermal energy into mechanical energy and highlights the importance of thermal efficiency in energy conversion processes.
Compressor: A device that increases the pressure of air or gas by reducing its volume, essential in the Brayton Cycle for raising the pressure of the intake air before combustion.
Turbine: A rotary mechanical device that extracts energy from fluid flow, converting it into useful work; in the Brayton Cycle, it generates power by utilizing the high-temperature gases produced during combustion.
Thermal Efficiency: A measure of how well a heat engine converts the heat from fuel into work output; higher thermal efficiency indicates a more effective engine, relevant for evaluating the performance of cycles like Brayton.
The Rankine cycle is a thermodynamic cycle that converts heat into work through a series of processes involving a working fluid, typically water or steam. It consists of four main processes: isentropic compression, isobaric heat addition, isentropic expansion, and isobaric heat rejection, making it a foundational concept in the study of heat engines and energy conversion systems.
Heat engine: A device that converts thermal energy into mechanical work, operating on various thermodynamic cycles including the Rankine cycle.
Thermal efficiency: A measure of how effectively a heat engine converts heat from fuel into work, expressed as the ratio of work output to heat input.
Reheat cycle: An enhancement of the Rankine cycle where steam is reheated after partial expansion to improve efficiency and reduce moisture content in the turbine.
Overall efficiency refers to the ratio of the useful output of a system to the total input energy supplied to that system. It provides a measure of how effectively a power cycle converts input energy into useful work, taking into account various factors like heat losses and irreversibilities that can affect performance. Understanding overall efficiency is crucial when evaluating and comparing different power generation systems, particularly when analyzing processes that involve multiple cycles or stages.
thermal efficiency: The ratio of the work output of a thermal cycle to the heat input, indicating how well a system converts heat energy into work.
exergy: A measure of the maximum useful work obtainable from a system as it moves towards equilibrium with its environment, highlighting the potential for energy conversion.
first law of thermodynamics: A fundamental principle stating that energy cannot be created or destroyed, only transformed from one form to another, which is key in analyzing energy systems.
A combined cycle power plant is a highly efficient power generation system that utilizes both gas and steam turbines to produce electricity. This setup captures the waste heat from the gas turbine's exhaust and uses it to generate steam, which then drives a steam turbine for additional power production, maximizing energy output from the same fuel source.
Gas Turbine: A type of combustion engine that converts natural gas or other liquid fuels into mechanical energy by rotating a turbine.
Heat Recovery Steam Generator (HRSG): A key component in combined cycle plants that captures exhaust heat from the gas turbine to produce steam for the steam turbine.
Thermal Efficiency: The ratio of useful work output to the heat input, indicating how effectively a power plant converts fuel into electricity.
Compressor efficiency is a measure of how effectively a compressor converts input energy into useful work, specifically in compressing a gas or vapor. It is a critical factor in evaluating the performance of compressors within combined gas-vapor power cycles, influencing both energy consumption and overall system effectiveness. Higher compressor efficiency means less energy is wasted, leading to improved cycle performance and lower operational costs.
Isentropic Efficiency: Isentropic efficiency compares the actual performance of a compressor to an ideal, reversible process, indicating how closely the real process approaches the maximum possible efficiency.
Thermal Efficiency: Thermal efficiency measures how effectively a cycle converts heat into work, taking into account both the work input and output throughout the cycle.
Compression Ratio: The compression ratio is the ratio of the outlet pressure to the inlet pressure of a compressor, playing a significant role in determining the compressor's performance and efficiency.
Turbine efficiency is a measure of how effectively a turbine converts the energy in a fluid into mechanical energy, typically expressed as a percentage. It indicates the ratio of useful work output to the energy input from the working fluid. High turbine efficiency is essential for maximizing the performance of energy systems, particularly in applications where energy conversion processes are critical.
isentropic efficiency: Isentropic efficiency is a specific measure of a turbine's performance that compares the actual work output to the work output of an ideal, isentropic process, highlighting the impact of irreversibilities.
power cycle: A power cycle is a series of processes that convert heat into work, typically involving a working fluid that undergoes phase changes to produce mechanical energy.
fluid dynamics: Fluid dynamics is the study of how fluids move and interact with their surroundings, which is crucial for understanding turbine performance and efficiency.
Regenerative feedwater heating is a process used in power plants to improve efficiency by using steam from the turbine to preheat the water before it enters the boiler. This method reduces the energy required to convert the feedwater into steam, thereby enhancing the overall performance of the combined gas-vapor power cycle. By recovering waste heat, it minimizes thermal losses and optimizes energy use.
Heat exchanger: A device that transfers heat between two or more fluids without mixing them, commonly used in regenerative feedwater heating systems.
Thermal efficiency: The ratio of useful work output from a system to the heat input, often increased by implementing regenerative heating techniques.
Condensate return: The process of returning condensed steam back to the boiler, which plays a crucial role in optimizing the feedwater heating cycle.
Net work output is the total amount of work produced by a thermodynamic cycle after accounting for the work input required to operate the system. In the context of combined gas-vapor power cycles, it reflects the efficiency and effectiveness of the cycle in converting energy into useful work, showcasing the balance between the energy provided and the energy consumed. This term is crucial for evaluating the performance of power cycles that integrate both gas and vapor systems.
thermal efficiency: The ratio of the net work output of a cycle to the heat input into the cycle, indicating how effectively a cycle converts heat energy into work.
specific work: The amount of work produced per unit mass of working fluid, often used to assess performance in thermodynamic cycles.
heat exchanger: A device that facilitates the transfer of heat between two or more fluids without mixing them, often used in combined cycles to enhance efficiency.
HRSG effectiveness refers to the efficiency with which a Heat Recovery Steam Generator (HRSG) captures and utilizes waste heat from gas turbines to produce steam for additional power generation. This term highlights how well the HRSG converts exhaust gases into usable energy, influencing the overall performance and efficiency of combined gas-vapor power cycles.
Heat Recovery Steam Generator (HRSG): A device that captures waste heat from gas turbine exhaust and uses it to generate steam, which can then be used to drive a steam turbine for additional power output.
Combined Cycle Power Plant: A power generation facility that combines gas and steam turbines to maximize efficiency, using waste heat from the gas turbine to produce steam for the steam turbine.
Thermal Efficiency: The ratio of useful work output from a power cycle to the heat input, indicating how effectively a system converts thermal energy into mechanical energy.
The number of transfer units (NTU) is a dimensionless measure used in heat and mass transfer operations to quantify the efficiency of a process, particularly in heat exchangers and absorption systems. It represents the number of times a unit of energy or mass is transferred from one phase to another and is essential for evaluating the performance of combined gas-vapor power cycles where heat recovery is critical.
Heat Exchanger: A device designed to efficiently transfer heat from one fluid to another without mixing them.
Thermal Efficiency: A measure of how well an energy conversion process transforms input energy into useful output energy, often expressed as a percentage.
Absorption Refrigeration: A refrigeration process that uses a heat source to provide the energy needed for cooling, commonly utilizing ammonia-water or lithium bromide-water solutions.