ABSTRACT
This chapter develops the concepts of chemical availability and fuel availability and the equations for their numerical calculations. The chemical availability is the available work from the substance at the state (T0, P0) both as the substance reacts chemically with those drawn from the environment and as the reaction products eventually come to the dead state. In an availability analysis, attention is given not only to the boiler second law efficiency but also to the distribution of availability loss and destruction in the overall process. The Gibbs function frequently is used when a process involves a chemical reaction. The Gibbs function represents the chemical potential of the substance in a given state and becomes very useful in the calculation of available work in a chemical reaction process. The chapter defines the environment for the calculations of the thermomechanical and diffusion availabilities, and confines those substances for which the products of reaction are also the components of the environment.
