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Related Quantities. Part A. Heat of Combustion and Potential Heat.


pdf icon Related Quantities. Part A. Heat of Combustion and Potential Heat. (798 K)
Babrauskas, V.

Chapter 8;

Heat Release in Fires, Elsevier Applied Science, NY, Babrauskas, V.; Grayson, S. J., Editor(s)(s), 207-223 pp, 1992.

Keywords:

heat release rate; fire protection engineering; heat of combustion; potential heat

Abstract:

In a combustion reaction, the essential quantity is the heat of reaction. Since in typical combustion reactions we are dealing with constant-pressure, rather than constant-volume systems, it is most convenient to work with enthalpies, rather than energies. The enthalpy, H (kJ), is defined as: H = U + PV where U is the energy (kJ), P is the pressure (kPa), and V is the volume (m3). In thermodynamics and engineering calculations, specific enthalpy, h, is often used (and also specific energy, u). Molar units (kJ/mol) for these terms are typical in thermodynamics calculations, while in engineering computations it is often convenient to adopt mass (kJ/kg) units.