
372 Forensic Engineering Fundamentals
by the HRR. Heat is positive when it enters a system and negative when it leaves the system.
By the work energy principle, in thermodynamic terms, work and heat are the methods of
energy transfer in a re.
e transfer of heat in a re and the associated work that is developed over the
release of the energy constitute the change of energy in the system of a re. is energy
in transition represents the internal energy of the constituents that burned as a result
of the re. We may think of this energy transition in terms of the rst law of thermo-
dynamics. A more detailed analysis of the transfer of heat is expla ...