Genetic Algorithms Applied To Direct-fired Lithium Bromide Absorption Chillers Ann Model For Steady-state Optimization

During the recent decades, direct-fired absorption chillers using waterlithium bromide as refrigerant have been widely used. However, because of the relatively short period of its domestic development, and limitations of its techniques, the operation cost of the units is quite high. As a result, the energy conservation and optimal control of direct-fired absorption chillers using waterlithium bromide as refrigerant becomes a hot topic in the research area of HAVC communities. A certain type?of direct-fired absorption chiller is taken as an example; the paper discusses the modeling and optimization of direct-fired absorption chillers using water-lithium bromide as refrigerant by integrating newly developed intelligent technologies: neural network and genetic algorithm.As this kind of chiller is a complex system with multi-input and multi-out put, conventional identification methods can抰 commendably resolve the highly non-linear modeling of direct-fired absorption chillers using water-lithium bromide as refrigerant. With self-learning and self-organizing ability, the neural network method has transferred the research focus from interior characters, and complicated thermodynamics equations of the chillers to the direct input/output of the system, simplifying the related problems greatly. Therefore, a high quality identification system model using forward feedback network BP algorithm is obtained by combining the actual experimental data and those provided by the manufacturers.Genetic algorithm is essentially a kind intelligent searching optimization technology. With the precondition that neural network model can accurately reflect the operation situation of the systems, the paper discusses how to effectively integrate the neural network and genetic algorithm, by utilizing the comprehensive searching ability, to minimize the energy consumption of the system under a specific load. The controlling state parameters of the system and the calculation results indicate the optimization result of a steady state is satisfactory.Results of the research indicate that the system operation cost has been in a large measure reduced by utilizing the intelligent technology in the optimization of the direct-fired absorption chillers using water-lithium bromide as refrigerant. Therefore, intelligent technology is practically of great use in HVAC systems.