Term
| What are the four phases of the Rankine cycle? |
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Definition
| Generation, Expansion, Condensate, and Feed |
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Term
| In a Rankine (steam) cycle, what are the parts in the Generation phase? |
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Definition
| Boiler, and the Superheater |
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Term
| In a Rankine (steam) cycle, what are the parts of the Expansion phase? |
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Definition
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Term
| In a Rankine (steam) cycle, what are the parts of the Condensate phase? |
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Definition
| Main Condenser, Condensate Pump, Air Ejector Condenser, MU Feed Tank |
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Term
| In a Rankine (steam) cycle, what are the parts in the Feed phase? |
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Definition
| Deaerating feed tank(DFT), Booster Pump, Economizer, and Feed Pump |
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Term
| What are the four purposes fo the DFT? |
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Definition
1) Removes air out of the water
2) Preheats water
3) Stores water
4) Maintain net positive suction for Main Feed Booster Pump |
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Term
| Classify the Rankine cycle. |
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Definition
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Term
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Definition
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Term
| What does the Automatic Boiler Control System maintain? |
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Definition
| It maintains the boiler water level pressure. |
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Term
| What does the MFP Differential Pressure Control System do? |
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Definition
| Ensures that the feed water-supply pressure is maintained at a constant value above the steam-drum pressure (75 psi). |
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Term
| What is an advantage and disadvantage of condensate depression? |
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Definition
Advantage: prevents cavitation and vapor lock of the MCP
Disadvantage: Causes cycle to be less efficient |
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Term
| In the nuclear power plant primary loop, what replaced the boiler? |
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Definition
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Term
| What is the purpose of the control rods? |
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Definition
Control rods control the fission process.
1) Shut down the reactor
2) Change avg. temperature
(shim out--raises temp. shim in--lowers temp shim all the way down--shuts off) |
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Term
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Definition
| Critical - Number of 1n’s is constant between generations |
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Term
| What does sub-critical mean? |
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Definition
| Sub-Critical - Number of 1n’s less than previous generation |
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Term
| What Super-Critical mean? |
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Definition
| Super-Critical - Number of 1n’s more than previous generation |
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Term
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Definition
| SCRAM - Emergency Rx Shutdown via inserting control rods (absorb 1n’s) |
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Term
| What are the four strokes of the diesel engine? |
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Definition
1) Intake
2) Compression
3) Combustion-Power Stroke
4) Exhaust |
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Term
| What are the five elements of every thermodynamic cycle? |
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Definition
PHHEW!!
Pumos, Heat receiver, Heat source, Engine, Work substance |
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Term
| How do the five elements of the thermodynamic cycle relate to a Gas Turbine Engine? |
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Definition
| Pump-compressor, Heat receiver-Atmosphere, Heat source- Combustion, Engine- turbine, Work substance-Exhaust gases |
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Term
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Definition
Crankshaft - rotating motion.
drives reduction gears, prop shaft, pump, generator (work output), and camshaft. |
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Term
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Definition
Camshaft - rotating motion.
controls operation of valves. |
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Term
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Definition
Piston - reciprocating motion
crown - closed end
skirt - open end |
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Term
| What is a connecting rod? |
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Definition
| Connecting rod - reciprocating/rotating motion. Connects piston to crankshaft. |
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Term
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Definition
| Piston rings - seal cylinder, distribute oil, transfer heat from piston to cylinder wall. |
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Term
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Definition
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Term
| What are the advantages of the Diesel Engine? |
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Definition
1) Efficient at all loads (high or low).
2)Low initial cost.
3)Easy to adapt to propulsion plant use.
4)Reliable.
5)Requires few operators. |
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Term
| What are the disadvantages of the Diesel Engine? |
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Definition
1)Several units required per shaft (very large units take up lots of space).
2)Frequent down periods for extensive maintenance.
3)Very noisy.
4)Flammability and storage of fuel
(Require Air for Combustion). |
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Term
| What are the Advantages of the Gas Turbine Engine? |
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Definition
1) Weight reduction of 70%
2) Compact, little or no cooling water req.s
3) Reduced manning requirements
4) Quicker response time
5) Faster Acceleration/deceleration
6) Modular replacement
7) Less vibrations
8) High reliability |
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Term
| What are the Disadvantages of the Gas Turbine Engine? |
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Definition
1) Very inefficient @ low partial loads
2) Not easily reversed
3) Many parts under high stress
4) High pitched noise (high energy- long range)
5) Needs large quantities of air
6) Large quantities of hot exhaust (IR target)
7) Cannot be repaired in place |
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Term
| What is the Brayton cycle? |
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Definition
| The gas turbine engine thermodynamic cycle is called the BRAYTON CYCLE. |
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Term
| Classify the Brayton cycle. |
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Definition
| Open Cycle,flow and unheated |
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Term
| How does split shaft operate? |
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Definition
HP Turbine runs compressor then sends exhaust to LP Turbine to run teh rest of the ship.
Power shaft is decoupled from compressor-thermodynamically coupled.
Allows both to operate at efficient speeds (not the same). |
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Term
| What three plant line-ups are available? |
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Definition
| Full Power->30 knots-all 4 GTE's, Split Power-up to 30 kts-one engine engaged per shaft, and Trail shaft-up to 19 kts-one GTE engaged on one shaft other shaft wind-milling |
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Term
| What are the four functions of the intake system for Gas Turbines? |
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Definition
1)Continuous supply of debris-free air.
Located to prevent ingestion of seawater
-Demisters
-Anti-icing – Intake heaters
-Foreign object damage (FOD) screen
2) Cooling air duct.
3) Acoustic insulation – Silencers.
4) Engine Removal. |
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Term
| What are the three functions of the exhaust system for Gas Turbines? |
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Definition
1) Expels exhaust to prevent re-ingestion.
2) Reduces exhaust temperature (IR signature and potential damage to personnel/equip).
-Exhaust plenum eductor (nozzles)
-Mixes exhaust air with outside air
3)Acoustic reduction – Silencers. |
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Term
| What are three advantages of the two stroke engine? |
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Definition
1) Two power strokes
2) Works upside down
3) lighter & more simple valve system |
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Term
| What are two disdvantages of a two stroke engine? |
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Definition
1) needs a blower to aid intake-power reduced
2) combustion process not as complete as a four stroke engine |
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