This paper presents the collaboration between Ansaldo Ricerche, Genova, and the Thermochemical Power Group (TPG) of the Dipartimento di Macchine Sistemi Energetici e Trasporti (DiMSET) of the Università di Genova for the development of advanced technologies in the distributed micro-cogeneration field.The work deals with the organization, theoretical background and application of a new software tool for the optimisation of the technical and economical design of microturbine recuperators. The code called CHEOPE (Compact Heat Exchanger Optimisation and Performance Evaluation) considered two types of recuperator concept, which proved to be the most promising for microturbine applications: the furnace-brazed plate-fin type and the welded primary surface type.This first part of the work summarises the general rules for design and performance evaluation of gas-gas heat exchangers, in the form suitable for the two types of recuperator considered. Moreover, the cost equation, employed to estimate the capital cost of these types of heat exchanger, is discussed.CHEOPE can be used both for solving the sizing problem and the rating problem.With regard to the former, the code is capable of a special optimisation of the recuperator matrix, which takes into account the compactness, the pressure drops and the expected cost of the device. The objective function can be customized according to the designer’s priorities. The tests performed for the validation are presented, and three case studies are illustrated for three different microturbine sizes, for a 50kW, a 100kW and a 500kW machine.
