CHAPTER 8 THERMODYNAMICS CYCLES (three laws of thermodynamics their…
three laws of thermodynamics
in mechanical engineering, etc.
Power generation by power cycles
for the power cycles.
isothermal process = extreme (very difficult to achieve)
Gas power cycle
consider the mixture of fuel and air is similar to the components of air mixture (since air composes by the majority of N2 in the mixture. And N2 has no chemical reaction).
Refrigeration by refrigeration cycles:
work of pumps (?)
definition of cycle
gas or vapor cycles
: related to the phases
closed or open cycles
: related to the open vs. closed cycles.
an overview of reciprocating engines
Note about the the air + fuel mixture:
because air contains 80% of N2 that does not have any reactions in the mixture of fuel and air. Therefore, we can consider this mixture as AIR only.
in the P-v diagram
includes 4 strokes: up-down-up-down, and 2 revolutions (what is revolution?)
OR include 2 strokes, 1 revolution.
Used because small and compacted.
efficiency (of the engine):
relates to heat in and out.
heat out q out = internal energy (because we have constant volume, and
cv at **
(because we use the assumption = use the
limitation: because of the mixture of air and fuel inside, so when it is pressured too much, this can be ignited before the functioning of spark =
similar to Otto cycle but in this case at P constant.
ratio of diesel cycle = ratio of Otto cycle: efficiency is similar.
: ideal - gas equation: PV/T = constant
or P/T = constant because V= constant (Otto cycle)