Boilers Flashcards
ideal gas law
also called the general gas equation. every gas has a constant that can be calculated under ideal conditions and the behavior of gasses can be predicted under ideal conditions
work
the product of force acting through a distance
3 modes of heat transfer
conduction, convection, and radiation
latent heat
heat to create phase change, no change in temperature, ie vaporization - water to steam
sensible heat
change in temperature, ie water getting hotter
Steam cycle
Generation - expansion - condensation - feed - Generation - expansion - condensation - feed
safety valves
- prevent overpressure
- open completely when set pressure is reached and stay open until pressure drops
- 2 common types: huddling chamber type and nozzle reaction type
- typically 3 on a propulsion boiler: 2 on steam drum, 1 on superheater
the removal of water from a boiler. Its purpose is to control boiler water parameters within prescribed limits to minimize scale, corrosion, carryover, and to remove suspended solids present in the system.
blowdown
excess air
more air than theoretically needed to achieve complete combustion (15% optimal). 17 pounds of Air to burn 1 pound of fuel
plate in the end of the straight mechanical atomizer that the oil sprays through, before the burner tip
sprayer plate
burner barrel with a burner tip attached with a cap nut. the quantity of oil is controlled by varying the oil pressure.
straight mechanical burner
similar to, but has higher turndown ratio than straight mechanical burner, due to an oil return path.
return-flow atomizer burner
auxiliary steam provides the energy to atomize the oil. 2 passages, one for oil, one for steam
racer steam atomizer
atomizes oil by throwing it off the edge of a tapered cup
rotary-cup atomizer
increases surface area of oil for rapid combustion
atomization