【作者】 刘义成；

【导师】 白雪莲；

【作者基本信息】 重庆大学 ， 供热、供燃气、通风及空调工程， 2011， 硕士

【摘要】 江水源热泵作为可再生能源的一种形式,将水体中储存的冷量或热量通过热泵提取后供给室内,具有节水、节电和减少污染物排放的巨大优势;冷却塔作为传统的制冷装置,在空气温度较低时使用优势明显。因此将两种技术联合应用,能充分发挥各自的优势,实现对资源的合理优化,最大限度的实现系统高效、经济、节能。本研究针对江水源热泵复合式系统应用的一些关键技术问题进行研究,从而为实现该系统的高效经济运行提供理论依据,为工程应用提供参考。对水源热泵复合式系统做全方位的分类,并说明各种系统形式的适用范围;分析了影响江水源热泵系统能效和常规冷却塔系统能效的逐时外部条件;依据能效优先的原则,对两种系统进行对比分析,推导出江水源热泵在不同负荷率下,相对常规系统节能的临界温差Δt的计算公式;综合考虑逐时江水温度、逐时室外空气湿球温度、逐时取水高差和逐时部分负荷率,遵从建筑空调冷热量供应侧和需求侧最佳匹配的理念,首次提出四类建筑江水源热泵复合式系统冷却塔负荷分担比例;基于水源热泵复合式系统的分类,考虑各方案的经济因素、技术因素、环境效益、社会影响四个方面,采用模糊层次分析法FAHP选择合理的系统方案;针对某江水源热泵+冷却塔复合式系统,在冷却塔50%负荷分担比例的前提下,提出6种可能最优的控制策略,利用matlab分别编程计算分析。研究结果表明:水源热泵复合式系统可以按照辅助系统的形式、作用方式、作用位置、组合方式等分类,在工程应用中负荷侧并联和冷热源侧并联两种形式应用较多;利用DEST建立典型模型,分析了不同建筑末端负荷特性,并分析了重庆地区江水温度、取水高差、空气温度等逐时变化,为系统负荷与能耗的动态耦合分析提供依据;江水源热泵相对节能临界温差Δt与取水高差H和部分负荷率PLR有关,本研究根据江水取水泵的变频限制,针对0.7<PLR<1和<0.5PLR<0.7分别推导出Δt不同的计算公式;按照全年“50h不保证率”计算得到辅助系统承担的负荷比例根据建筑物不同略有差别,即住宅:0.2—0.4,办公:0.28—0.58,商场:0.48—0.68,酒店:0.4—0.6;根据模糊层次分析法FAHP,五种方案的权重系数分别为常规系统0.1803,土壤源热泵系统0.1988,江水源热泵系统0.1930,江水源+土壤源热泵系统0.2172,土壤源+冷却塔系统0.2106,得出复合式系统权重系数较高,方案应用时可优先考虑;对江水源热泵复合式系统可能最优的6种控制策略分别编程计算分析,得出对于酒店、住宅等全天空调系统均需开启的建筑物,复合式系统优势更加明显;系统能耗受到机组和输配系统的双重影响,对于本研究案例两者之间的最佳耦合点为:热泵机组79.01%,输配系统20.99%;6种控制策略中,动态控制策略节能效果最好,节能率为8.49%,温差控制策略3( t_r- t_w>2时开启辅助系统)节能效果也较好,节能率为7.67%。本文研究表明,水源热泵复合式系统具有推广应用的价值,可以解决在夏初及夏末时间段江水源热泵取水高差大、部分负荷率低造成的系统能效较低的问题。更多还原

【Abstract】 As a form of renewable energy, river water source heat pump, which getting the cooling and heating capacity stored in water, has advantage of water saving, power saving, and reducing pollutant discharging; cooling tower as a tranditional cooling device has obvious superiority when use in the air temperature is lower.So combined of the two technologies can give full play their respective strengths, achieve the rational optimization of resources and maximum system efficiency, economy, energy saving.In this study, research on several key technical problems of river water source heat pump hybrid system ,so provide the theoretical basis for hybrid system’s efficiency and economic operation and offer reference for engineering application. We do a full range of categories of hybrid systems of water source heat pump, and describe the application of various systems in the form.; analysis of the hourly external conditions impact of river water source heat pump system efficiency and conventional cooling tower system efficiency; based on priority of energy efficiency principle, comparative analysis the two kind system, calculation formula of relative energy saving critical temperature difference to general system under different loading rates is derived; considering the hourly river temperature, hourly outdoor air’s wet bulb temperature, hourly water height and hourly rate of part-load, following the best matched concept of building air conditioning load supply side and the demand side, first put forward load sharing proportion of hybrid system of water source heat pump for four kind of architecture; based on the classification of hybrid water source heat pump system, consider economic factors, technical factors, environmental and social impact of various options,use fuzzy analytic hierarchy process choose reasonable system solutions; according to a river water source heat pump and cooling tower system, under the cooling tower 50% load allocation proportion put forward six may optimal control strategy and programming calculation and analysis using matlab.The results show that: Water source heat pump systems can follow the form of auxiliary system, mode of action, role position, combinations, etc. and in engineering applications load side and the heat source side in parallel are more; establish typical model using DEST to analyze the load characteristics of different construction end and analyze of Chongqing river temperature, water height, hourly air temperature, providing basis for system load and enery dynamic coupling analysis; river water source heat pump energy-saving critical temperature relative to water height and part-load ratio, based on the intake pump frequency limit, for 0.7 <PLR <1 and < 0.5 <PLR <0.7 were derived from a different formula; according the annual "50h does not guarantee rate" the load ratio of auxiliary system to bear slightly different according to different buildings, which house 0.2 to 0.4, office: 0.28 -0.58, shopping malls :0.48-0.68, hotel 0.4-0.6; According to FAHP, the weight coefficients of five kinds of programs were 0.1803 for the conventional system, Ground Source Heat Pump, 0.193 for water source heat pump, 0.2172 for WSHP and GSHP, 0.2106 for GSHP and cooling tower, obtained hybrid system has a higher weight factor, the program may give priority to applications; for river water source heat pump hybrid system may six best control strategies were programmed calculation and analysis, come to the hotel, residential air conditioning systems, etc. need to be open all day have more obvious advantages of hybrid systems; Energy consumption by unit and distribution system double impact, the best coupling of case study between the two points: heat pump 79.01%, transmission and distribution system20.99%; Six kinds of control strategy, the best energy-saving is dynamic control strategies, energy-saving rate of 8.49%, temperature control strategy 3 ( t r- t w> 2 on auxiliary systems) are also have well energy saving effect, energy-saving rate of 7.67%.This study shows that hybrid river water source heat pump technology has application value, can solve the problem of low system efficiency cosed by Large taking water elevation and low part-load in the early summer and late summer period更多还原