Browsing by Author "Xie, G."

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    Improvement of the Performance for an Absorption Refrigeration System with Lithium bromide-water as Refrigerant by Increasing Absorption Pressure
    (Energy Systems Laboratory (http://esl.tamu.edu), 2006) Xie, G.; Sheng, G.; Li, G.; Pan, S.
    Because the absorption refrigeration system uses the Lithium bromide- water solution as refrigerant, it is profitable for the environment that human beings are living since the values of ODP and GWP of the refrigerant almost are zero. However, the low COP of the absorption machine was limited seriously to compete with the refrigeration machine that is drove by electricity. Therefore, most researchers focus their attention on the improvement of performance of the absorption system through many approaches. In this paper, an improved cycle was adopted to raise the pressure inside the absorber of the machine in order to intensify the absorption effect of thick Lithium bromide solution and enhance the COP of the absorption refrigeration system. A mathematical model that is used for predicting the performance of the system will be established, and the influence of pressure change on the overall performance of the machine will be discussed in the paper.
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    The Technical and Economical Analysis of a Centralized Air-Conditioning System with Cold Storage Refrigeration in High-Rise Residential Buildings
    (Energy Systems Laboratory (http://esl.tamu.edu), 2006) Xiang, C.; Xie, G.
    In recent years, the application of a centralized air-conditioning system (CACS) with cold storage refrigeration in high-rise residential buildings has gradually increased. Due to the large difference between civil residential buildings and commercial buildings, characteristics such as the cooling load in summer and the storey height must be considered in the design of the air-conditioning system, and the cold storage equipment and the cold supplying means must be properly selected. The option of establishing centralized air-conditioning equipment with cold storage and supplying unified cold in high-rise residential buildings is analyzed objectively with technical and economical methods in this paper. It is not true that the option of supplying unified cold can save energy all the time. CACS with cold storage will not always be economical. Based on a 27-floor building, the running costs in summer and the first costs are both compared between CACS with and without cold storage refrigeration. The cold storage method selected will significantly impact the residents.
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    The Technical and Economical Analysis of the Air-conditioning System Usage in Residential Buildings in Beijing
    (Energy Systems Laboratory (http://esl.tamu.edu), 2006) Sheng, G.; Xie, G.
    In this paper, we show that the air-conditioning usage in residential buildings in Beijing grows rapidly in relation to the development of civil construction. More and more people are not satisfied with the current style of only using split air-conditioning units in residential buildings, and are using the central air-conditioning system in residential buildings. To determine the best air conditioning mode, a residential tower building with 22 layers was chosen for analysis. The advantages and disadvantages of the central air-conditioning system and the residential multi-unit air-conditioning equipment system and the LiBr absorption chiller were compared based on calculating the first-cost and the annual cost (according to providing cooling 90 days annually). The predicted results show the economical feasibility of using the refrigerating units in air-conditioning systems in Beijing region, and point out the developing directions for the future.