Environmental Engineering Reference
In-Depth Information
400
350
350
Total Tons/year = 874
306
300
250
214
200
150
100
50
3
0.2
0
Wood-fired HHs
Oil-fired
Wood Heaters*
Coal-fired
Natural Gas
*Includes non-certified & certified wood stoves, pellet stoves, and masonry heaters
Fig. 3.18 Estimated PM
2.5
emissions caused by residential heating with various fuels in Fairbanks
(Alaska) [
75
]
Functionally, external combustion engines produce vehicle propulsion through
the adiabatic energy of gases that are burnt and evacuated at high pressure and
speed—sometimes passing through a turbine. For this reason, many researchers do
not include them in the class of proper engines. Additionally, rocket engines use
other oxidisers, much stronger than oxygen, instead of air. This is because, on the
one hand, rocket engines must produce as much energy as possible in a very short
time, and on the other hand, air supply is no longer possible when leaving the
atmosphere.
Most internal combustion engines are engines with spark (Otto) or compression
(Diesel) ignition. If spark-ignition engines are almost exclusively petrol engines
and are used for cars or smaller applications (boat engines, low-voltage generating
sets, etc.), depending on their size, diesel engines use diesel oil, light or heavy fuel
oil and even coal dust or carbon black (marine engines).
Historically speaking, one should also mention steam engines, either Watt-
Carnot or Stirling, which were the basis for industrial and water and road transport
development for almost 200 years. However, applications for historical machinery
are anticipated for the future [
76
].
3.3.2.1 External Combustion Engines (Jet and Rocket Engines)
Almost without exception, medium or long-range wide body jet airliners use jet
engines or turbojet engines. The distribution of nanoparticles released by jet
engines in the northern hemisphere is given in Fig.
3.19
. The analytical
