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Test your basic knowledge |
Energy Engineering
Start Test
Study First
Subject
:
engineering
Instructions:
Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can
study here
.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.
This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.
1. Are turbofans - which derive >80% of their thrust from the ducted fan rather than the high- velocity exhaust. Turbopros and other turbine- based engines also common for helicopters - ships - propeller- based aircraft - etc.
Trace emissions of coal
Most Jet Engines on Commercial Aircraft
Ethanol in combustion engines
Otto Cycle
2. Hard=bituminous - Brown=subbituminous/lignite
4 stokes of spark ignited 4 stroke
Ethanol in combustion engines
diesel engines
Europe Hard vs. Brown Coal
3. Distillate fraction (heavier than naptha) - though it requires some additional treatment for sulfur removal -
NG compostion from ground
NG composition in pipeline
How to get diesel
Coal Conversion Technologies
4. Combustion rate mostly limited by heat and mass transfer rather than kinetics and is therefore much slower than in a gasoline engine - hence the constant pressure assumption - No spark plug required - glow plugs only provide local warming of system f
Compression ignited (diesel)
CNG for transportation
Fracking
NG transportation
5. Brayton Cycle
Jet Engines Cycle
Protect Jet Engine Fan Blades
Diesel Cycle
natural gas emissions
6. Less efficient than either Otto or Diesel cycle at same pressure ratio/compression ratio - but in practice pressure ratio is higher leading to higher efficiencies.
Otto Cycle
How to get diesel
Brayton Cycle efficiency
50
7. Fuel is injected in cylinder at much higher pressures than gasoline fuel injection and through injectors designed to atomize fuel to small droplets that rapidly vaporize and burn.
Jet Engines Lifetime/Reliability
Trace emissions of coal
Fuel Injection of compression ignited
Diesel vs Gasoline engines
8. Modern only output CO2 and no significant impact on other pollutants - Most Coal Power are old and many have significant impact on air pollution
Compression ignited (diesel)
Ethanol in combustion engines
Modern vs. Old Coal Power Plants
Protect Jet Engine Fan Blades
9. Inlet/intake - compression - expansion/combustion/power - exhaust
Diesel differences from gasoline
Coal Production and Environment
4 stokes of spark ignited 4 stroke
Europe Hard vs. Brown Coal
10. More reliable than reciprocating engines because: continuous operation and fewer moving parts
Protect Jet Engine Fan Blades
NG as delivered to a home and most industries
How to get diesel
Jet Engines Lifetime/Reliability
11. Bituminous coals are in the _____ - subbituminous coals in most of the west (but not Utah) - and lignites primarily in Texas and North Dakota.
Gas/Brayton Cycle coal power
Diesel differences from gasoline
Eastern US
gasoline composition and formation
12. your engine is knocking (igniting the gas too early when piston coming up instead of while at top) - High compression engines need higher octane fuels.
Ethanol in combustion engines
4 stokes of spark ignited 4 stroke
US coal reserves
why use higher octane fuels
13. Fischer Tropsh synthesis
Making Diesel Like fuels from Coal - NG - and biomass
Cost of NG for consumer
US coal reserves
Diesel vs Gasoline engines
14. Much lower energy density than gasoline and can be corrosive or damaging to engines and seals. Because it requires less oxygen to burn - it has slightly better engine efficiency. However - its lower energy density means a car gets considerably lower
CNG for transportation
Compression ignited (diesel)
size of reactors for subbitmunious vs. bituminous
Ethanol in combustion engines
15. Not produced from any single fraction of crude in the fractionation column but rather are blends and reformates designed specifically for regional markets and specifications/regulations
Diesel differences from gasoline
gasoline composition and formation
Cetane number
Jet Engines Lifetime/Reliability
16. Critical pressure (218 psi) and above - 38-39% efficient - supercritical from 45-47% efficient - materials limit max temp to 600 degC - pressure ratios up to 10 -000 because condenser reaches really low pressures
Trace emissions of coal
Rankine Cycle Coal Conversion/Steam Turbines
Crude oil is transformed into commercial products how?
Cost of NG for consumer
17. Drilling - then set up production wells with nothing above surface - production decreases exponentially with time
why use higher octane fuels
Cost to Generate Coal Power
NG production
Protect Jet Engine Fan Blades
18. Contains an odorant - deliberately added so leaks will be noticed
NG as delivered to a home and most industries
Gas/Brayton Cycle coal power
Cetane number
size of reactors for subbitmunious vs. bituminous
19. Not very common - small particulate and SO2 and some NOx are problems for this cycle with coal
Gas/Brayton Cycle coal power
50
Compressor Stator vs. Turbine Stator
Eastern US
20. Refineries - which include fractionation columns - reformers - hydro crackers - catalytic crakers - cokers - reforming - and hydro treating. Know the essential role of each of these operations.;
Compression ignited (diesel)
Largest Coal Consumers
Compressor Stator vs. Turbine Stator
Crude oil is transformed into commercial products how?
21. Hg - As - trace other metals - no dioxins and furans
Cost of NG for consumer
Modern vs. Old Coal Power Plants
NG as delivered to a home and most industries
Trace emissions of coal
22. Same as Brayton cycle
diesel engines
subbituminous vs. bituminous coals
Diesel Cycle
NG simple cycle
23. Cetane numbers greater than ___ generally have no advantage over a fuel of 50. Common cetane numbers are 40-45 and 45-50 for regular and premium diesel fuels.
Crude oil is transformed into commercial products how?
50
Eastern US
Cost to Generate Coal Power
24. Constant volume combustion - isentropic and adiabatic compression and expansion - 2 stroke and 4 stroke engines use (gasoline engines)
Gas/Brayton Cycle coal power
Otto Cycle
Jet Engines Cycle
How to get diesel
25. 2 stroke and 4 stroke - Combustion rate limited by gas - phase kinetics and is very rapid.
Octane Rating
why use higher octane fuels
Spark ignited engines (gasoline)
Coal Production and Environment
26. Fracture rock with water and other stuff - replace with sand - suck out liberated NG
Fracking
Compression ignited (diesel)
NG transportation
size of reactors for subbitmunious vs. bituminous
27. Constant pressure combustion - isentropic and adiabatic compression and expansion
Diesel Cycle
Protect Jet Engine Fan Blades
Most Jet Engines on Commercial Aircraft
jet Engine Pressure Ratio
28. Higher than compression ratio in diesel or gasoline engines (note that pressure ratio is not exactly the same as a compression ratio).
jet Engine Pressure Ratio
Diesel vs Gasoline engines
4 stokes of spark ignited 4 stroke
Modern vs. Old Coal Power Plants
29. China - and rapidly growing - India also rapdily growing
NG compostion from ground
diesel engines
Compressor Stator vs. Turbine Stator
Largest Coal Consumers
30. Not too good for it. Strip mined or deep/mountain top mined
subbituminous vs. bituminous coals
Coal Production and Environment
NG as delivered to a home and most industries
Eastern US
31. Measure of a fuels ability to resist compression ignition - with iso- octane having an octane number of 100 and n - heptane an octane number of 0. (n - octane has an octane number of -10).
Modern vs. Old Coal Power Plants
Octane Rating
4 stokes of spark ignited 4 stroke
Gas/Brayton Cycle coal power
32. 150 yrs
Diesel Cycle
natural gas emissions
US coal reserves
CNG for transportation
33. Brayton cycle with exhaust powering a Rankine Cycle (efficiencies of up to 60%) - possibly most economical choice - can't respond to load changes as rapidly as simple cycle
Compression ignited (diesel)
NG simple cycle
Coal and Air Pollution
Combined Cycle
34. From inlet temperatures with cooling of blades and thermal barrier couplings
Protect Jet Engine Fan Blades
Natural Gas Reserves?
NG as delivered to a home and most industries
why use higher octane fuels
35. Anthracites - bituminous coals - subbituminous coals - lignites.
50
Coal Ranking (oldest to newest)
Octane Rating
Coal Conversion Technologies
36. Steam Turbines (Rankine Cycle) - Gas Turbines (Brayton Cycle) - Combined Cycle (not very economically feasible) - Liquid Fuels and Other products (chemicals - Fischer Tropsh - Coal to Methanol for gasoline but less history)
Trace emissions of coal
coal rank and H:C ratio and O:C ratio
Otto Cycle
Coal Conversion Technologies
37. Measures the ability of a fuel to pressure ignite and in this regard is the opposite of the octane number.
Trace emissions of coal
Compressor Stator vs. Turbine Stator
Cetane number
NG production
38. More expensive - heavier - and more durable/reliable than gasoline engines - Diesel cycle is less efficient than gasoline cycle at the same compression ratio - but in practice is more efficient because compression ratios are about 2x higher.
Diesel vs Gasoline engines
jet Engine Pressure Ratio
NG production
Compression ignited (diesel)
39. Less CO2 and most other pollutants than other combustion fuels
jet Engine Pressure Ratio
Coal Conversion Technologies
Most Jet Engines on Commercial Aircraft
natural gas emissions
40. Is dominantly CH4 - but the ethane content is always >1 % and important to the fuel
Compressor Stator vs. Turbine Stator
Europe Hard vs. Brown Coal
NG composition in pipeline
50
41. Good alternative to petroleum based fuels?
Jet Engines Lifetime/Reliability
CNG for transportation
Brayton Cycle efficiency
NG as delivered to a home and most industries
42. Coal contributes to essentially every criteria air pollutant and to CO2 and Hg. In most cases (except CO) - coal is a major contributor.
Cetane number
NG composition in pipeline
Coal and Air Pollution
diesel engines
43. Little more than half=fuel cost - rest is transportation and distribution
Compressor Stator vs. Turbine Stator
Coal Ranking (oldest to newest)
why use higher octane fuels
Cost of NG for consumer
44. Almost zero aromatics in it
Diesel vs Gasoline engines
Cost of NG for consumer
Spark ignited engines (gasoline)
Diesel differences from gasoline
45. Occurs (with a few exceptions) in the intake manifold prior to the air entering the cylinder. Air entering cylinder is a mixture of air and vaporized fuel.
Crude oil is transformed into commercial products how?
NG compostion from ground
Spark ignited engines location of fuel injection
Ethanol in combustion engines
46. 100 bar inside pipelines (1/600 of normal volume) - pumping stations every 40 to 100 mi - pipelines maintained and made sure safe by pigs(devices that measure stuff to make sure nothing's wrong) distribution pipelines are lower pressure and plastic
NG transportation
natural gas emissions
Diesel Cycle
US coal reserves
47. Low sulfur vs. high sulfur - bituminous used to provide most power - but switching to cleaner Wyoming subbituminous
subbituminous vs. bituminous coals
Trace emissions of coal
Octane Rating
natural gas emissions
48. Methane (70-90%) - heavier hydrocarbons (up to 20% through C4) - CO2 (up to 8% - but occasionally much higher) - H2O (usually saturated) - sometimes H2S (up to 5%) - oxygen (< 0.2%) nitrogen (up to 5%) - and other trace quantities.
Most Jet Engines on Commercial Aircraft
Diesel Cycle
NG compostion from ground
Largest Coal Consumers
49. Subbituminous much bigger because produce reflective ash
size of reactors for subbitmunious vs. bituminous
subbituminous vs. bituminous coals
Coal Production and Environment
Spark ignited engines (gasoline)
50. Have broader range of fuels - have higher compression ratios - nearly always super/turbo charged
Spark ignited engines location of fuel injection
Coal Conversion Technologies
Trace emissions of coal
diesel engines