导热塑料盘管蓄冰槽传热性能的研究
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摘要
在当前全球(特别是我国)对能源需求越来越迫切的形势下，冰蓄冷空调系统以其简单的结构和显著的社会经济效益得到了日益广泛的应用。在目前应用的多种蓄冰系统中，内融式冰盘管蓄冰系统具有可靠性高，结冰融冰比较迅速等优点，因此得到了广泛的应用。
冰盘管材料的热导率对其传热性能有重要的影响。目前，钢材等金属材料由于其具有较高的热导率而被广泛地用作盘管材料，但乙二醇溶液对钢等金属的腐蚀性会对盘管工作的长期稳定性产生严重影响。
本文提出采用新型的导热塑料来代替钢作为盘管材料。导热塑料是一种新型材料，它既具有普通塑料的耐化学腐蚀性能，又具有比普通塑料高得多的导热能力。为此，本文做了以下研究工作：
1．建立内融式冰盘管在蓄冰和融冰时的数学模型，从理论上分析了盘管材料对蓄冰槽传热性能的影响；
2．搭建实验台，测试导热塑料盘管蓄冰槽的传热性能，通过实验结果与理论结果的比较来验证数学模型；
3．全面比较导热塑料盘管与钢盘管，包括它们的传热性能、流动阻力、加工工艺、产品价格等；
4．比较“完全冻结”与“不完全冻结”方式在蓄冷和释冷时的传热性能；
5．分析进口温度和流量对释冷过程传热性能的影响。
最后，对全文进行了总结。
Nowadays, power is in short supply all over the world, especially in China. Ice storage air conditioning system has been used more and more widely due to its simple structure and outstanding social and economic benefits. Among all the ice storage systems, internal-melt ice-on-coil has been widely used because of its high reliability and relatively high charging and discharging rate.
Thermal conductivity of tube material plays an important role in heat transfer characteristics of ice-on-coil. Nowadays, such metal as steel has been widely used as tube material, but the corrosiveness of secondary refrigerant (glycol water) to metal tube has negative effect on the long-term stability.
This paper proposes to use a kind of novel conductive plastics instead of steel as tube material. In comparison with steel, novel conductive plastics have good anti-corrosiveness and their thermal conductivity is much higher than that of common plastics.
In order to study the heat transfer characteristics of conductive plastic ice-on-coil, the following works have been done in this paper:
1. A numerical model of the heat transfer characteristics of conductive plastic ice-on-coil has been developed during both charging and discharging periods. The impacts of thermal conductivity on the heat transfer characteristics of ice-on-coil have been analyzed by using this model.
2. An experimental apparatus is built up to study its heat transfer characteristics and to verify the numerical model.
3. Comparison between metal ice-on-coil and conductive plastic ice-on-coil has been made in their heat transfer property, flow pressure drop, installation, processing
method and price.
4. Comparison between "partial charged" method and "fully charged" method of internal-melt ice-on-coil in their heat transfer property during both charging and discharging periods has also been made.
5. The impacts of inlet temperature of ice-on-coil and mass flowrate of secondary refrigerant during both charging and discharging periods have been analyzed.
In the end, the summary of this paper is also given.
冰盘管材料的热导率对其传热性能有重要的影响。目前，钢材等金属材料由于其具有较高的热导率而被广泛地用作盘管材料，但乙二醇溶液对钢等金属的腐蚀性会对盘管工作的长期稳定性产生严重影响。
本文提出采用新型的导热塑料来代替钢作为盘管材料。导热塑料是一种新型材料，它既具有普通塑料的耐化学腐蚀性能，又具有比普通塑料高得多的导热能力。为此，本文做了以下研究工作：
1．建立内融式冰盘管在蓄冰和融冰时的数学模型，从理论上分析了盘管材料对蓄冰槽传热性能的影响；
2．搭建实验台，测试导热塑料盘管蓄冰槽的传热性能，通过实验结果与理论结果的比较来验证数学模型；
3．全面比较导热塑料盘管与钢盘管，包括它们的传热性能、流动阻力、加工工艺、产品价格等；
4．比较“完全冻结”与“不完全冻结”方式在蓄冷和释冷时的传热性能；
5．分析进口温度和流量对释冷过程传热性能的影响。
最后，对全文进行了总结。
Nowadays, power is in short supply all over the world, especially in China. Ice storage air conditioning system has been used more and more widely due to its simple structure and outstanding social and economic benefits. Among all the ice storage systems, internal-melt ice-on-coil has been widely used because of its high reliability and relatively high charging and discharging rate.
Thermal conductivity of tube material plays an important role in heat transfer characteristics of ice-on-coil. Nowadays, such metal as steel has been widely used as tube material, but the corrosiveness of secondary refrigerant (glycol water) to metal tube has negative effect on the long-term stability.
This paper proposes to use a kind of novel conductive plastics instead of steel as tube material. In comparison with steel, novel conductive plastics have good anti-corrosiveness and their thermal conductivity is much higher than that of common plastics.
In order to study the heat transfer characteristics of conductive plastic ice-on-coil, the following works have been done in this paper:
1. A numerical model of the heat transfer characteristics of conductive plastic ice-on-coil has been developed during both charging and discharging periods. The impacts of thermal conductivity on the heat transfer characteristics of ice-on-coil have been analyzed by using this model.
2. An experimental apparatus is built up to study its heat transfer characteristics and to verify the numerical model.
3. Comparison between metal ice-on-coil and conductive plastic ice-on-coil has been made in their heat transfer property, flow pressure drop, installation, processing
method and price.
4. Comparison between "partial charged" method and "fully charged" method of internal-melt ice-on-coil in their heat transfer property during both charging and discharging periods has also been made.
5. The impacts of inlet temperature of ice-on-coil and mass flowrate of secondary refrigerant during both charging and discharging periods have been analyzed.
In the end, the summary of this paper is also given.
引文
1 张国强，龚光彩等，能源、环境与空调制冷，制冷学报，2000，(3)
2 胡兴邦，朱华，叶水泉，冯踏青，储冷空调系统原理、工程设计及应用，浙江大学出版社，1997．
3 严德隆，张维君，空调蓄冷应用技术，中国建筑工业出版社，1997．6
4 叶水泉，陈国邦，空调蓄冷技术及其发展，低温工程，2001，No．1
5 王晓亮，蓄冰板单元传热性能研究，浙江大学硕士学位论文，1998．12
6 方贵银，蓄冷空调工程实用新技术，人民邮电出版社，2000，5
7 S.M.Hasnain. Review On Sustainable Thermal Energy Storage Technologies, Part Ⅱ: Cool Storage. Energy Convers, Mgmt Vol.39, No. 11, 1998.
8 Ibrahim Dincer. On Thermal Energy Storage Systems and Applications in Buildings. Energy and Building, Vol.34, 2002.
9 郭开华，气体水合及其在空调蓄冷技术中的应用，制冷，2，1994，22—28
10 王力军，朱京国，胡定科，内肋管壳式冰蓄冷器及其性能的实验研究，暖通空调，3，1998，40—43
11 吕树申，王世平，林培森，气体水合物蓄冷技术研究报告之一——发展概况，制冷，1，1994，8—14
12 郭开华，舒碧芬，空调蓄冷及气体水合物蓄冷技术，制冷，1995．4，15—21
13 潘雨顺，吴建国，贾燕芳，冰蓄冷低温送风空调技术研究现状与发展优势，低温与特气，2001．10，Vol19，No．5
14 周伟坤，陈林，陈国邦，新型导热塑料在蓄冰过程中的传热性能研究，低温与超导，2002．Vol．30．No．3
2 胡兴邦，朱华，叶水泉，冯踏青，储冷空调系统原理、工程设计及应用，浙江大学出版社，1997．
3 严德隆，张维君，空调蓄冷应用技术，中国建筑工业出版社，1997．6
4 叶水泉，陈国邦，空调蓄冷技术及其发展，低温工程，2001，No．1
5 王晓亮，蓄冰板单元传热性能研究，浙江大学硕士学位论文，1998．12
6 方贵银，蓄冷空调工程实用新技术，人民邮电出版社，2000，5
7 S.M.Hasnain. Review On Sustainable Thermal Energy Storage Technologies, Part Ⅱ: Cool Storage. Energy Convers, Mgmt Vol.39, No. 11, 1998.
8 Ibrahim Dincer. On Thermal Energy Storage Systems and Applications in Buildings. Energy and Building, Vol.34, 2002.
9 郭开华，气体水合及其在空调蓄冷技术中的应用，制冷，2，1994，22—28
10 王力军，朱京国，胡定科，内肋管壳式冰蓄冷器及其性能的实验研究，暖通空调，3，1998，40—43
11 吕树申，王世平，林培森，气体水合物蓄冷技术研究报告之一——发展概况，制冷，1，1994，8—14
12 郭开华，舒碧芬，空调蓄冷及气体水合物蓄冷技术，制冷，1995．4，15—21
13 潘雨顺，吴建国，贾燕芳，冰蓄冷低温送风空调技术研究现状与发展优势，低温与特气，2001．10，Vol19，No．5
14 周伟坤，陈林，陈国邦，新型导热塑料在蓄冰过程中的传热性能研究，低温与超导，2002．Vol．30．No．3