Test your basic knowledge |

Energy Engineering

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. 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






2. 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






3. Constant pressure combustion - isentropic and adiabatic compression and expansion






4. 2 stroke and 4 stroke - Combustion rate limited by gas - phase kinetics and is very rapid.






5. 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.






6. Fracture rock with water and other stuff - replace with sand - suck out liberated NG






7. 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






8. Not too good for it. Strip mined or deep/mountain top mined






9. Good alternative to petroleum based fuels?






10. Compressor stator (trailing edge points axially) - turbine stator (trailing edge has significant tangential component).






11. Hard=bituminous - Brown=subbituminous/lignite






12. 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






13. Distillate fraction (heavier than naptha) - though it requires some additional treatment for sulfur removal -






14. More reliable than reciprocating engines because: continuous operation and fewer moving parts






15. 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






16. China - and rapidly growing - India also rapdily growing






17. 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.






18. 150 yrs






19. Same as Brayton cycle






20. Constant volume combustion - isentropic and adiabatic compression and expansion - 2 stroke and 4 stroke engines use (gasoline engines)






21. Brayton Cycle






22. Inlet/intake - compression - expansion/combustion/power - exhaust






23. Coal contributes to essentially every criteria air pollutant and to CO2 and Hg. In most cases (except CO) - coal is a major contributor.






24. 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.






25. 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.






26. 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.






27. Not very common - small particulate and SO2 and some NOx are problems for this cycle with coal






28. Modern only output CO2 and no significant impact on other pollutants - Most Coal Power are old and many have significant impact on air pollution






29. Bituminous coals are in the _____ - subbituminous coals in most of the west (but not Utah) - and lignites primarily in Texas and North Dakota.






30. Have broader range of fuels - have higher compression ratios - nearly always super/turbo charged






31. Subbituminous much bigger because produce reflective ash






32. Mid 80s






33. Little more than half=fuel cost - rest is transportation and distribution






34. Low sulfur vs. high sulfur - bituminous used to provide most power - but switching to cleaner Wyoming subbituminous






35. Less CO2 and most other pollutants than other combustion fuels






36. 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






37. Fischer Tropsh synthesis






38. 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.






39. Hg - As - trace other metals - no dioxins and furans






40. Drilling - then set up production wells with nothing above surface - production decreases exponentially with time






41. 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






42. Refineries - which include fractionation columns - reformers - hydro crackers - catalytic crakers - cokers - reforming - and hydro treating. Know the essential role of each of these operations.;






43. Is dominantly CH4 - but the ethane content is always >1 % and important to the fuel






44. Contains an odorant - deliberately added so leaks will be noticed






45. From inlet temperatures with cooling of blades and thermal barrier couplings






46. Higher than compression ratio in diesel or gasoline engines (note that pressure ratio is not exactly the same as a compression ratio).






47. 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






48. 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.






49. Almost zero aromatics in it






50. 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).