Festin, Charmaine Cheska M.
BSME 3 – 1
Assignment No. 2
1. What is reversible and irreversible process in thermodynamics work done?
Reversible Process is a process where the system and surroundings can be returned to their
exact initial states by following the exact reverse path. These are theoretical and impossible
to achieve in reality. While on the other hand, Irreversible Process a process where the
system and surroundings cannot be returned to their exact initial states by following the
exact reverse path. All real-world processes are irreversible due to friction, heat loss, etc.
For both processes, the work done is the transfer of energy between the system and the
surroundings due to a force acting through a distance.
2. What
is
the
difference
between
IHP
and
BHP
in
the
compressor?
Indicated Horse Power (IHP) represents the theoretical power developed within the
cylinders of an engine or compressor. It is calculated based on the pressure-volume changes
of the working fluid (usually air or a gas) during the compression process. In an ideal
scenario, IHP accounts only for the work done by the expanding gas against the piston,
ignoring factors like friction and inefficiencies. On the other hand, Brake Horse Power
(BHP) is the actual usable power delivered by the compressor shaft. BHP considers realworld losses due to friction, heat transfer, and mechanical components. It is always lower
than IHP. Understanding this difference helps engineers optimize compressor designs and
improve
overall
efficiency.
3. Illustrate the P-H and T-S diagram of a vapor compression refrigeration cycle.
References:
•
Ling, S. J., Moebs, W., & Sanny, J. (2016). Introduction. Pressbooks.online.ucf.edu.
https://pressbooks.online.ucf.edu/osuniversityphysics2/chapter/introduction/
•
Reversible & Irreversible Processes - Definition, Examples & FAQs. (n.d.).
BYJUS. https://byjus.com/physics/reversible-irreversible-processes/
•
Refrigeration cycle & Pressure Enthalpy. (2017, July 31). SlideShare.
https://www.slideshare.net/slideshow/refrigeration-cycle-pressureenthalpy/78417480