蒸发式风冷冷水机组性能分析与优化

发布时间：2018-01-17 22:11

本文关键词：蒸发式风冷冷水机组性能分析与优化　出处：《湖南科技大学》2013年硕士论文　论文类型：学位论文

【摘要】：建筑能耗在国家总能耗中占有重要比重，减少建筑能耗是实现我国能源环境可持续发展的必然要求。空调能耗是建筑能耗的主体，降低空调能耗，对促进建筑节能减排具有重要意义。风冷冷水机组具有结构紧凑、系统简单、安装方便及投资费用低等突出优点，在中小型建筑中得到了较广泛的应用。然而，与水冷式冷水机组相比，风冷式冷水机组能效较低，不利于建筑节能。因此，本文试图采用一种简单、可靠、有效的方法，来提高风冷冷水机组的能效，促进风冷冷水机组的运行节能。蒸发式风冷冷水机组是将直接蒸发冷却器与风冷冷水机组相结合，通过直接蒸发冷却器降低冷凝器进风温度，从而降低机组冷凝温度，提高机组能效。本文在建立直接蒸发冷却器和风冷冷水机组数学模型基础上，通过MATLAB计算机软件编程，仿真分析了蒸发式风冷冷水机组的性能的影响因素：气候条件、迎面风速及填料厚度。为了更加准确合理地评价蒸发式风冷冷水机组在各地的节能潜力，本文提出采用机组季节能效比增加作为评价指标，并以该指标作为优化目标。优化了机组填料厚度，给出了蒸发式风冷冷水机组在我国各主要城市使用的最佳填料厚度。为进一步考虑机组负荷随建筑负荷变化，同时考虑机组在不同冷凝控制策略时的节能潜力，本文还建立了蒸发式风冷冷水机组的详细分析模型，利用该模型，分析了机组在不同负荷率下的节能潜力大小。为进一步帮助工程设计人员分析设计蒸发式风冷冷水机组，在理论研究基础上，本文开发了机组计算软件包。通过本文的研究，可以得出以下有益结论：（1）在给定的气候条件和迎面风速下，存在一个最佳的填料厚度，使得机组性能最佳。针对我国的气候条件，最佳填料厚度的取值在80~140mm之间。（2）蒸发式风冷冷水机组性能受负荷率和冷凝控制策略的影响较大，比较分析结果表明：变冷凝温度控制比定冷凝温度控制具有更高的节能潜力。（3）优化的蒸发式风冷冷水机组较传统风冷式冷水机组具有较高的节能潜力，有较大的推广应用前景，尤其是在我国西部和北部地区，，节能潜力更大。
[Abstract]:Building energy consumption occupies an important proportion in the national total energy consumption. Reducing building energy consumption is the inevitable requirement to realize the sustainable development of energy environment in China. Air conditioning energy consumption is the main part of building energy consumption, reducing air conditioning energy consumption. The air-cooled chillers are widely used in small and medium-sized buildings because of their advantages such as compact structure, simple system, easy installation and low investment cost. Compared with water-cooled chillers, air-cooled chillers have lower energy efficiency and are not conducive to building energy saving. Therefore, this paper attempts to adopt a simple, reliable and effective method to improve the energy efficiency of air-cooled chillers. Promote the operation of air-cooled chillers energy-saving. Evaporative air-cooled chillers combine direct evaporative coolers with air-cooled chillers to reduce the inlet air temperature of the condenser and thus to reduce the condensing temperature through the direct evaporative cooler. On the basis of establishing mathematical model of direct evaporative cooler and air-cooled chiller, this paper is programmed by MATLAB computer software. The factors affecting the performance of evaporative air-cooled chillers, such as climatic conditions, direct wind speed and packing thickness, are simulated and analyzed. In order to evaluate the energy saving potential of evaporative air-cooled chillers in different places more accurately and reasonably. In this paper, the increase of unit seasonal energy efficiency ratio is used as the evaluation index, and this index is taken as the optimization target, and the packing thickness of the unit is optimized. The optimum packing thickness of evaporative air-cooled chillers used in major cities of China is given. In order to further consider the variation of unit load with building load and the energy saving potential of units under different condensing control strategies, a detailed analysis model of evaporative air-cooled chillers is established and used in this paper. The energy saving potential of the unit under different load rates is analyzed. In order to further help the designers to analyze and design evaporative air-cooled chillers, based on the theoretical research. In this paper, the software package of unit calculation is developed. Through the research in this paper, we can draw the following useful conclusions: 1) under the given climatic conditions and the direct wind speed, there is an optimum packing thickness, which makes the performance of the unit optimal, aiming at the climate conditions of our country. The optimum packing thickness is between 80 mm and 140 mm. 2) the performance of evaporative air-cooled chillers is greatly affected by the load rate and condensing control strategy. The results of comparison and analysis show that the variable condensing temperature control has a higher energy saving potential than the fixed condensing temperature control. 3) the optimized evaporative air-cooled chillers have higher energy saving potential than the traditional air-cooled chillers, and have a great prospect of popularization and application, especially in the western and northern regions of China.
【学位授予单位】：湖南科技大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU831.4

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