Application Research Of Second Best Solution Group Analysis Method In Chilled Source System With Complex Variables

As the chilled source system involved a huge number of complex equipment, running frequently change in the environment. The actual operation condition deviate from the design conditions and cause influence the operational efficiency of it. As the chilled source system is the building relationship of energy consumption and temperature control, low-efficiency operation not only waste the energy but also reduce the quality of indoor-temperature control and even can not to meet the requirements of environment control, the design and the control of the chilled source system are relating to the advantages and disadvantages about the whole system. Therefore, many sides to simulate and optimize the design and operation of the chilled source system are necessary.This article consider the physical characteristics of the chilled source system, and set up the operation model of chilled water pump group and the model of chilled water pipe net with multiple variables. Using the chilled water pump group operation model to analyze the operating characteristic of pump group with different types, and simulate the operating characteristic with different rated flow and different bypass pressure control. Base on the simulated data, by the yearly energy consumption of chilled water pump groups as index, by using an optimized random step method and sub-optimal solutions group method, to optimizing the type of the pump group, and setting up the analysis method of energy consumption area, can provide theoretical guidance for the energy-saving operation of a chilled pump group and energy saving space in future development. The results show us that use an optimized random step method and sub-optimal solutions group method can solve the predicament about local optimum and convergence.Chilled water pipe network operation model by the AHU operation model and the network dynamic model of chilled water. This paper to the office and contains 20 different range of pipe network and the office a reverse-return chilled water system and a direct-return chilled water system as an example, analyzes the different state of outdoor air and indoor control state, delivery requirements, chilled water supply temperature under different operating characteristics, at the same time in the early construction of office floors each room use an optimized random step method and sub-optimal solutions group method for load distribution optimization, the results showed: using an optimized random step method and sub-optimal solutions group method can solve the predicament about local optimum and convergence. The direct-return chilled water system face when load changes in total energy consumption and energy consumption characteristics is better.