Cold Generation Systems: A Theoretical Approach

Abstract

The objective of this study was to derive the thermodynamic formulae for ideal combined driving and cooling cycles when the objective of the overall cycle is to produce cooling by using a high-temperature heat source. For this it has been necessary to investigate absorption cooling thermodynamics and to focus on the analysis of one-, two- and three-stage cycles and multi-stage cycles in general. This paper has investigated the absorption thermodynamic principles involved to obtain simple formulae, in a similar way to the Carnot cycle. The first driving cycle considered has a high-temperature source such as a combustion process. From this driving cycle the heat dissipated at the lower temperature is used to drive the next consecutive driving and/or absorption cooling cycles. All the work produced in the driving cycles is used for the cooling cycles with mechanical compressors, whereas the dissipated heat of the last driving cycle is used to drive the absorption cycles. A simple universal law for driving and cooling cycles has been derived, which is applicable to combined heat and power (cogeneration) systems.