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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. 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
gasoline composition and formation
50
size of reactors for subbitmunious vs. bituminous
2. Less CO2 and most other pollutants than other combustion fuels
Jet Engines Cycle
NG compostion from ground
50
natural gas emissions
3. Same as Brayton cycle
Octane number of gas sold in Utah
Spark ignited engines (gasoline)
NG simple cycle
Octane Rating
4. Fracture rock with water and other stuff - replace with sand - suck out liberated NG
Fracking
Jet Engines Lifetime/Reliability
natural gas emissions
jet Engine Pressure Ratio
5. 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
Cost of NG for consumer
Combined Cycle
NG as delivered to a home and most industries
Spark ignited engines (gasoline)
6. 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).
NG simple cycle
Octane Rating
coal rank and H:C ratio and O:C ratio
Protect Jet Engine Fan Blades
7. Subbituminous much bigger because produce reflective ash
How to get diesel
NG compostion from ground
size of reactors for subbitmunious vs. bituminous
Otto Cycle
8. Refineries - which include fractionation columns - reformers - hydro crackers - catalytic crakers - cokers - reforming - and hydro treating. Know the essential role of each of these operations.;
NG simple cycle
Crude oil is transformed into commercial products how?
diesel engines
Fuel Injection of compression ignited
9. Drilling - then set up production wells with nothing above surface - production decreases exponentially with time
Coal Production and Environment
Compression ignited (diesel)
Diesel vs Gasoline engines
NG production
10. Hard=bituminous - Brown=subbituminous/lignite
Compressor Stator vs. Turbine Stator
Europe Hard vs. Brown Coal
Cost of NG for consumer
Jet Engines Lifetime/Reliability
11. Not too good for it. Strip mined or deep/mountain top mined
Diesel differences from gasoline
Compressor Stator vs. Turbine Stator
Coal Production and Environment
diesel engines
12. 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.
Cost to Generate Coal Power
How to get diesel
Gas/Brayton Cycle coal power
NG compostion from ground
13. 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
Jet Engines Lifetime/Reliability
Trace emissions of coal
50
Rankine Cycle Coal Conversion/Steam Turbines
14. Contains an odorant - deliberately added so leaks will be noticed
Protect Jet Engine Fan Blades
50
NG as delivered to a home and most industries
CNG for transportation
15. Almost zero aromatics in it
Diesel differences from gasoline
Combined Cycle
Making Diesel Like fuels from Coal - NG - and biomass
Spark ignited engines location of fuel injection
16. 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.
Brayton Cycle efficiency
Cetane number
NG simple cycle
Trace emissions of coal
17. Many decades and up to 100 yrs left reserves increasing due to fracking and tight gas recovery almost always seen with oil and frequently without
Natural Gas Reserves?
CNG for transportation
Eastern US
US coal reserves
18. Good alternative to petroleum based fuels?
Eastern US
Coal Ranking (oldest to newest)
CNG for transportation
NG production
19. 2 stroke and 4 stroke - Combustion rate limited by gas - phase kinetics and is very rapid.
Natural Gas Reserves?
Octane Rating
Spark ignited engines (gasoline)
NG compostion from ground
20. 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
gasoline composition and formation
Largest Coal Consumers
50
Crude oil is transformed into commercial products how?
21. 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.
why use higher octane fuels
Octane Rating
coal rank and H:C ratio and O:C ratio
50
22. Higher than compression ratio in diesel or gasoline engines (note that pressure ratio is not exactly the same as a compression ratio).
Gas/Brayton Cycle coal power
Octane Rating
jet Engine Pressure Ratio
Jet Engines Lifetime/Reliability
23. Coal- fired power generation costs are roughly 50% capital and the remaining fuel and operating costs. Fuel costs have remained stable and low historically - making coal an attractive investment for power
Cost to Generate Coal Power
4 stokes of spark ignited 4 stroke
Cost of NG for consumer
Compressor Stator vs. Turbine Stator
24. Measures the ability of a fuel to pressure ignite and in this regard is the opposite of the octane number.
NG simple cycle
Cetane number
Modern vs. Old Coal Power Plants
Compressor Stator vs. Turbine Stator
25. Compressor stator (trailing edge points axially) - turbine stator (trailing edge has significant tangential component).
Compression ignited (diesel)
subbituminous vs. bituminous coals
50
Compressor Stator vs. Turbine Stator
26. From inlet temperatures with cooling of blades and thermal barrier couplings
Fracking
Spark ignited engines (gasoline)
Protect Jet Engine Fan Blades
Europe Hard vs. Brown Coal
27. 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
Protect Jet Engine Fan Blades
Combined Cycle
Ethanol in combustion engines
Largest Coal Consumers
28. 150 yrs
Ethanol in combustion engines
NG simple cycle
NG as delivered to a home and most industries
US coal reserves
29. China - and rapidly growing - India also rapdily growing
Making Diesel Like fuels from Coal - NG - and biomass
Coal Conversion Technologies
Eastern US
Largest Coal Consumers
30. Distillate fraction (heavier than naptha) - though it requires some additional treatment for sulfur removal -
Cost of NG for consumer
How to get diesel
Crude oil is transformed into commercial products how?
Rankine Cycle Coal Conversion/Steam Turbines
31. 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
Diesel Cycle
Otto Cycle
Combined Cycle
Compression ignited (diesel)
32. Hg - As - trace other metals - no dioxins and furans
Trace emissions of coal
Gas/Brayton Cycle coal power
size of reactors for subbitmunious vs. bituminous
NG transportation
33. Inlet/intake - compression - expansion/combustion/power - exhaust
NG simple cycle
Coal Production and Environment
4 stokes of spark ignited 4 stroke
Octane number of gas sold in Utah
34. Anthracites - bituminous coals - subbituminous coals - lignites.
Cetane number
Jet Engines Cycle
Gas/Brayton Cycle coal power
Coal Ranking (oldest to newest)
35. Is dominantly CH4 - but the ethane content is always >1 % and important to the fuel
50
Cetane number
NG as delivered to a home and most industries
NG composition in pipeline
36. Low sulfur vs. high sulfur - bituminous used to provide most power - but switching to cleaner Wyoming subbituminous
Jet Engines Lifetime/Reliability
subbituminous vs. bituminous coals
CNG for transportation
Trace emissions of coal
37. Bituminous coals are in the _____ - subbituminous coals in most of the west (but not Utah) - and lignites primarily in Texas and North Dakota.
Eastern US
Cost to Generate Coal Power
Compression ignited (diesel)
subbituminous vs. bituminous coals
38. Constant volume combustion - isentropic and adiabatic compression and expansion - 2 stroke and 4 stroke engines use (gasoline engines)
Otto Cycle
Largest Coal Consumers
4 stokes of spark ignited 4 stroke
Diesel vs Gasoline engines
39. Brayton Cycle
NG production
Jet Engines Cycle
4 stokes of spark ignited 4 stroke
Fuel Injection of compression ignited
40. Coal rank correlates with both hydrogen:carbon and oxygen:carbon ratio - with rank decreasing with increasing values of both ratio. ex. anthracite low ratios and lignites have high ratios
Diesel differences from gasoline
Combined Cycle
coal rank and H:C ratio and O:C ratio
Gas/Brayton Cycle coal power
41. Fischer Tropsh synthesis
Making Diesel Like fuels from Coal - NG - and biomass
Jet Engines Cycle
Cost of NG for consumer
diesel engines
42. 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
CNG for transportation
gasoline composition and formation
NG transportation
Diesel Cycle
43. Mid 80s
Octane number of gas sold in Utah
Coal Ranking (oldest to newest)
Otto Cycle
Gas/Brayton Cycle coal power
44. 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.
Fuel Injection of compression ignited
Coal Ranking (oldest to newest)
Jet Engines Cycle
Combined Cycle
45. More reliable than reciprocating engines because: continuous operation and fewer moving parts
Jet Engines Lifetime/Reliability
Diesel Cycle
Octane Rating
why use higher octane fuels
46. Little more than half=fuel cost - rest is transportation and distribution
Gas/Brayton Cycle coal power
Cost of NG for consumer
Diesel differences from gasoline
Cetane number
47. 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.
Most Jet Engines on Commercial Aircraft
Coal and Air Pollution
Protect Jet Engine Fan Blades
Cost to Generate Coal Power
48. Coal contributes to essentially every criteria air pollutant and to CO2 and Hg. In most cases (except CO) - coal is a major contributor.
Coal and Air Pollution
50
CNG for transportation
Eastern US
49. 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)
natural gas emissions
Coal Ranking (oldest to newest)
Largest Coal Consumers
Coal Conversion Technologies
50. 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.
Coal Production and Environment
Diesel vs Gasoline engines
US coal reserves
why use higher octane fuels