Evaluation of absorption cycles with respect to COP and economics
Abstract The calculation of the performance of absorption heat pump cycles or the comparison of different types of machine cannot be done in a reasonable way without considering the first cost of the machine and especially the cost of the heat exchangers, as their area and particularly the distribution of the area between the respective components of the heat pump determine the COP. Therefore it makes sense only to compare machines that are optimized in this respect. A good way to evaluate cycles is to calculate the maximum COP in terms of the total cost of the heat exchangers. For that purpose a computer program was developed for different absorption heat pump cycles with water as refrigerant. The calculation method is simple and thus the result reliable. The program is suitable for evaluating double-lift, single-, double- and some triple-effect cycles, each one with different absorption fluids and with different options, such as different solution flows (parallel, serial), different types of absorber (spray- or falling-film absorber), and different types of generator (pool- or falling-film generator). With this instrument different cycles or similar cycles with different features can be compared. An economically significant estimation of the performance of a cycle working under defined conditions is possible.