Plant Systems Quiz #3 Flashcards
(35 cards)
The ______ is the best cycle in terms of thermal efficiency.
Carnot Cycle
In a supercritical cycle/system the less fuel consumption is observed because the biggest heat was eliminated which is the ______.
latent heat of vaporization
In Reheat cycle, the ______ is the steam that goes back to the boiler (reheater) and then goes to the ______ as a ______ steam.
cold reheat steam, IP turbine, hot reheat
In a close heater (FW heater) the ______ temperature is higher than the ______ temperature of the extracted steam that supplies the heater.
feedwater outlet, condensate outlet
A ______ is also a ______ where distinction between ______ and ______ phases do not ______.
supercritical water, supercritical fluid, liquid, gas, exist
Rankine cycle is more stable than Carnot cycle because three (3) stable points of the cycle which are ______, ______, and ______, compared to Carnot it has only ______ stable conditions.
saturated liquid @ Pcondenser, saturated vapor @ Pboiler, and saturated liquid @ Pboiler, two
Furnace enclosure designs for ______ (SC), ______ (USC), and ______ (A-USC) are of temperatures (degC); ______, ______, and ______ respectively.
supercritical, ultra supercritical, advanced ultra supercritical, 540, 600, 700
______, a gentleman from Glasgow in 1855 develop a power cycle that is the basis of Thermal Power Plant steam cycles today.
William Rankine
The famous Combined Cycle is a ______ as the higher cycle and a ______ as the lower cycle.
Brayton Cycle, Rankine Cycle
Multi-stage reheating is possible but not practical. One major reason is because the vapor exiting the turbine exhaust will be ______ at higher temperature thus ______ ______.
superheated vapor, decreases, thermal efficiency
In a ______ boiler system in order to prevent economizer ______ damage, a recirculating valve is installed between the ______ tube and the _______, while in a supercritical ______, a ______ _______ pump is installed between the connecting ______ and the ______.
subcritical, tube, downcomer, economizer, steam generator system, boiler, circulation, sphere, economizer
In a power plant, there is no ______ steam, the only use is in the following ______ and ______ to become ______ steam then passing different stages at constant pressure and temperature, namely; ______, ______, ______, ______.
saturated, roof, walls, superheated, low-temperature superheater, SH DIV panel, SH platen, SH final (Final Superheater)
Modern coal-fired power plants operate between ______ degC to ______ degC and pressure larger than ______ bars.
375, 700, 221
- Supercritical region is defined by ______ MPa and ______ degC.
22.1, 374
Three Basic Improvements to have a higher Rankine Cycle Efficiency:
a.) Superheat the steam entering the turbine
b.) Lower down condenser pressure
c.) Increase boiler pressure
The advantage of regenerative Rankine cycle is at lower temperature heat is added.
FALSE
In a supercritical system, the power block is called Boiler, Turbine, Generator.
FALSE
An open feedwater is basically a mixing chamber. Ideally, the mixture leaves the heater as saturated liquid at extraction steam pressure.
TRUE
The disadvantage of Reheat Rankine is the steam quality effluent of the low-pressure turbine can be kept very high.
FALSE
Having plenty of extractions in the power plant cycle saves more fuel because it heats better the feedwater heater.
FALSE
In supercritical point, steam and water cannot be distinguished.
TRUE
The operational flexibility of Supercritical technology is shorter start-up time because it operates at lower hg (enthalpy vapor state) and hf (enthalpy liquid state) of steam and water.
FALSE
Regenerative cycle is enough to have a better efficiency for big capacity Power Plant.
FALSE
A close feedwater heater operates at different pressures of extracted steam and feedwater. It also operates in higher pressures.
TRUE
