Upper bounds for thermally driven cooling cycles optimization derived from the f-(φ)over-bar chart method

An analytical approach for the economical evaluation and optimization of absorption and an ejector cooling cycle is presented. The f-(phi) over bar chart method is used here to correlate the basic design parameters of the solar system with the system cooling cycle performance. The optimization is carried out by using the life cycle cost savings function as the objective function. This function is expressed in terms of the capital cost and the operating cost, the later expressed in terms of the solar fraction f. The optimization is carried out for a lithium-bromide chiller and an ejector cooling cycle with R11 as working fluid. A numerical example is presented to compare the optimum bound regions for both cycles, in terms of the capital costs respective to each system. The Carnot cycle limit is also determined. Upper bounds for economical feasibility in terms of the costs of the auxiliary energy and electric energy are also set down. The design approach presented here is convenient to determine the optimum conditions in terms of the monthly means of the global radiation incident on a horizontal surface. (C) 2003 Elsevier Ltd. All rights reserved.