Join 60,000+ competitive exam aspirants
or with email
Your Cart
SubtotalтВ╣0
TotalтВ╣0
Examoogle тАв User тАв info@examoogle.com тАв EE-2024-8821
Chapter 1 of 12 тАв Page 1 of 248ЁЯФТ Protected PDF тАв Watermarked
Join 60,000+ competitive exam aspirants
The thermal efficiency of a steam plant is defined as ________.
the ratio of heat of combustion of coal to the heat equivalent of mechanical energy transmitted to the turbine shaft
the ratio of heat equivalent of mechanical energy transmitted to the turbine shaft to the heat of combustion of coal
the ratio of heat of combustion of coal to the heat equivalent of electrical output
the ratio of heat equivalent of electrical output to the heat of combustion of coal
the ratio of heat equivalent of mechanical energy transmitted to the turbine shaft to the heat of combustion of coal
The thermal efficiency of a steam power plant is the ratio of the energy output available at the turbine shaft to the total energy input supplied by the combustion of fuel. It represents the conversion efficiency of thermal energy from the fuel into mechanical work within the heat engine cycle.
ASME PTC 6 (Performance Test Code on Steam Turbines)
The thermal efficiency of a steam power plant is the ratio of the energy output available at the turbine shaft to the total energy input supplied by the combustion of fuel. It represents the conversion efficiency of thermal energy from the fuel into mechanical work within the heat engine cycle.
╬╖thтАЛ=mfтАЛ├ЧCVWturbineтАЛтАЛ
╬╖thтАЛ=Heat┬аof┬аCombustion┬аof┬аCoalHeat┬аEquivalent┬аof┬аMechanical┬аEnergyтАЛ
In a steam plant, chemical energy in coal is converted to thermal energy in the boiler. This steam expands through the turbine, converting heat energy into mechanical shaft work. The efficiency measures how effectively the plant captures this energy, limited by thermodynamic constraints like the Carnot cycle limits and heat losses in the boiler and condenser.
Thermal efficiency accounts for the losses in the combustion process and turbine expansion.
It is different from overall plant efficiency which includes electrical generator losses.
Higher steam temperatures and pressures generally improve thermal efficiency.
Typical values for modern steam power plants range from 30% to 45%.
Provides a direct measure of thermodynamic cycle performance.
Independent of generator efficiency for isolated analysis.
Does not account for losses in electrical transmission or auxiliary equipment.
Cannot be used to estimate net plant output without accounting for house load.
Performance monitoring of steam power cycles.
Comparing design efficiency between different power plant configurations.
The overall efficiency is defined as (Electrical Output) / (Heat of Combustion of Coal).
Option A is inverted and mathematically incorrect for an efficiency definition.
Option C and D relate to overall efficiency rather than thermal/cycle efficiency.
B is correct тАФ the thermal efficiency is defined as the ratio of the heat equivalent of mechanical energy transmitted to the turbine shaft to the heat of combustion of coal.
Remember that 'Thermal Efficiency' typically refers to the heat engine (cycle) performance, while 'Overall Efficiency' refers to the plant performance including the generator and auxiliary systems.
Get instant step-by-step AI explanations, full shift Previous Year Papers (SSC GD, RRB, SSC JE), and regional rank analysis on the official Examoogle App.
Free Download тАв 100K+ Aspirants