editors proceedings of the 8th international symposium on … · 2016. 2. 10. · hazim b. awbi...
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Angui LiYingxin ZhuYuguo LiEditors
Proceedings of the 8th International Symposium on Heating, Ventilation and Air Conditioning
Lecture Notes in Electrical Engineering 262
Volume 2: HVAC&R Component and Energy System
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Lecture Notes in Electrical Engineering
Volume 262
For further volumes:http://www.springer.com/series/7818
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Angui Li • Yingxin Zhu • Yuguo LiEditors
Proceedings of the 8thInternational Symposiumon Heating, Ventilationand Air Conditioning
Volume 2: HVAC&R Componentand Energy System
123
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EditorsAngui LiXi’an University of Architecture
and TechnologyXi’anPeople’s Republic of China
Yingxin ZhuTsinghua UniversityBeijingPeople’s Republic of China
Yuguo LiThe University of Hong KongHong KongPeople’s Republic of China
ISSN 1876-1100 ISSN 1876-1119 (electronic)ISBN 978-3-642-39580-2 ISBN 978-3-642-39581-9 (eBook)DOI 10.1007/978-3-642-39581-9Springer Heidelberg New York Dordrecht London
Library of Congress Control Number: 2013945148
� Springer-Verlag Berlin Heidelberg 2014This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part ofthe material is concerned, specifically the rights of translation, reprinting, reuse of illustrations,recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission orinformation storage and retrieval, electronic adaptation, computer software, or by similar or dissimilarmethodology now known or hereafter developed. Exempted from this legal reservation are briefexcerpts in connection with reviews or scholarly analysis or material supplied specifically for thepurpose of being entered and executed on a computer system, for exclusive use by the purchaser of thework. Duplication of this publication or parts thereof is permitted only under the provisions ofthe Copyright Law of the Publisher’s location, in its current version, and permission for use mustalways be obtained from Springer. Permissions for use may be obtained through RightsLink at theCopyright Clearance Center. Violations are liable to prosecution under the respective Copyright Law.The use of general descriptive names, registered names, trademarks, service marks, etc. in thispublication does not imply, even in the absence of a specific statement, that such names are exemptfrom the relevant protective laws and regulations and therefore free for general use.While the advice and information in this book are believed to be true and accurate at the date ofpublication, neither the authors nor the editors nor the publisher can accept any legal responsibility forany errors or omissions that may be made. The publisher makes no warranty, express or implied, withrespect to the material contained herein.
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Preface
The 8th International Symposium on Heating, Ventilation, and Air Conditioning—ISHVAC2013 is held in Xi’an, China from October 19 to 21, 2013, organized byXi’an University of Architecture and Technology and co-organized by TsinghuaUniversity and The University of Hong Kong. The proceedings consist of over 220peer-reviewed papers presented at the ISHVAC2013. We sincerely hope that the8th International Symposium of Heating, Ventilation, and Air Conditioning willprovide a good platform again to HVAC experts and researchers in China andelsewhere share their latest research findings and new technology development,and looking into the future of HVAC.
Xi’an has more than 3,000 years of history as one of the four great ancientcapitals of China. Xi’an has now re-emerged as one of the important cultural,industrial, and educational centers in China. History tells us a lot. The history ofHVAC is much shorter. Addington (2001) wrote, after the 1918–1919 influenzapandemic, which killed more people than World War I, ‘‘Engineers and manu-facturers were quick to capitalize on the public’s concern with cleanliness, andpointed out that the air handler could produce ‘manufactured weather’ that wascleaner and purer than what nature provided (Carrier 1919). In spite of thecontinued work of open-air enthusiasts such as Winslow and Dr. Leonard Hillduring the next several decades to challenge mechanical systems, most of the earlyventilation laws remained in place and the air-handler-based system became thestandard for conditioning interior environments.’’ The new revitalization ofnatural ventilation and new development of mixed-mode ventilation in the past10 years confirms the wisdom of Winslow and Dr. Leonard Hill.
The success of HVAC is and will also be judged in the balance of providingpeople a comfortable and healthy indoor environment and using the minimumresources and energy. The key to the success of HVAC is in understanding thehuman physiological needs in thermal comfort and healthy air, and the rolesplayed by human behavior, which is dynamical in nature. We cannot just focus onthe HVAC technologies as we have done in the past 100 years.
Urbanization is a huge thing in rapidly developing countries such as in China.More than 50 % of the world’s population now lives in cities. The urban popu-lation will reach 1 billion by 2030 in China. In the next 10 years, it is expected atleast 1 % of the population will become urban dwellers every year. The expec-tation for better indoor environment is also on the rise in China and other
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developing countries as the living standard rises. Building consumes a largeproportion of our energy in the world. Efficient HVAC is the key in high per-formance buildings. Continuing urban warming has been observed and studied inmany megacities in the world. Just imagine if you are asked to cool the air in aMong Kok district in Hong Kong or Wang Fu Jing Street in Beijing by a fewdegrees, what would you do? When shall we design a city just like designing abuilding? What can HVAC engineers and researchers help?
Xi’an literally means ‘‘Peaceful in the West’’ in Chinese, and it was historicallyknown as Chang An (‘‘Perpetually Peaceful’’). We also wish that the world willnot only be peaceful, but also sustainable. The HVAC Engineers and Researchershave a great role to play.
Finally, the conference organizing and the high quality of the proceedings arethe result of many people’s hard work, dedication, and support. The first appre-ciation goes to the Members of the International Scientific Committee. Greatappreciation should also go to many people who worked tirelessly on the Orga-nizing Committee. We greatly appreciate all the sponsors and cooperators for theirspecial contributions.
We also express our thanks to the authors who enthusiastically presented theirwork, ideas, and results.
Angui LiYingxin Zhu
Yuguo Li
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International Scientific Committee
Yi Jiang (China)Jiaping Liu (China)Phillip J. Jones (UK)Hazim B. Awbi (UK)William Bahnfleth (USA)Pradeep Bansal (NZ)Mark Bomberg (USA)Qingyan Chen (USA)Zhenqian Chen (China)Qihong Deng (China)Shiming Deng (HK, China)Lei Fang (DK)Leon R. Glicksman (USA)Yanling Guan (China)Per Heiselberg (DK)Jan Hensen (NL)Sture Holmberg (SE)Xiang Huang (China)Shinsuke Kato (JP)Angui Li (China)Baizhan Li (China)Xianting Li (China)Yuguo Li (HK, China)Zhiwei Lian (China)Martin W. Liddament (UK)John C. Little (USA)Weiding Long (China)Shuzo Murakami (JP)Vincenzo Naso (IT)Jianlei Niu (HK, China)Bjarne W. Olesen (DK)Saffa Riffat (USA)Dirk Saelens (BE)Jan Sundell (China)
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Shin-ichi Tanabe (JP)Kwok wai Tham (SG)Peter V. Nielsen (DK)Markku Virtanen (FI)Fenghao Wang (China)Ruzhu Wang (China)Shengwei Wang (HK, China)Yew Wah Wong (SG)Hongxing Yang (HK, China)Xudong Yang (China)Yang Yao (China)Harunori Yoshida (JP)Hiroshi Yoshino (JP)Shijun You (China)Chuck Yu (UK)Guoqiang Zhang (China)Jensen Zhang (USA)Xiaosong Zhang (China)Xu Zhang (China)Yinping Zhang (China)Jianing Zhao (China)Rongyi Zhao (China)Xudong Zhao (UK)Neng Zhu (China)Yingxin Zhu (China)
viii International Scientific Committee
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Organizing Committee
Angui LiYingxin ZhuYuguo LiLei ZhaoYi WangYanfeng LiuZhiwei WangYuesheng FanQiuhui YanXiaohong NanXiong LiuQinghong Zheng
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Contents
Part I Energy System
1 Net-Zero Energy Technical Shelter . . . . . . . . . . . . . . . . . . . . . . . 3Chen Zhang, Per Kvols Heiselberg and Rasmus Lund Jensen
2 The Study on Paraffin-Water Emulsion PCMwith Low Supercooling Degree . . . . . . . . . . . . . . . . . . . . . . . . . . 19Xiyao Zhang, Jianlei Niu, Jianyong Wu and Shuo Zhang
3 Analysis of Energy Utilization on Digestion BiogasTri-Generation in Sewage Treatment Works . . . . . . . . . . . . . . . . 27Zhiyi Wang, Hongxing Yang, Jinqing Peng and Lin Lu
4 Approach and Practice of District Energy Planning UnderLow-Carbon Emission Background . . . . . . . . . . . . . . . . . . . . . . . 37Baoping Xu, Changbin Zhu and Wenlong Xu
5 Study on the Heat Insulation Performance of EMU Structure . . . 47Huasheng Xiong and Xuquan Li
6 Thermal Matching of Heat Sources for District Heating SystemBased on Energy Quality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55Kan Zhu, Jianjun Xia, Yi Jiang and Hao Fang
7 Performance Analysis of Single Well Groundwater HeatPump Systems Based on Sand Tank Experiment . . . . . . . . . . . . . 63Wei Song, Long Ni, Yang Yao and Jeffrey D. Spitler
8 Investigating the Thermal Performance of HorizontalSlinky Ground Heat Exchangers for Geothermal Heat Pump. . . . 73Ping Cui, Jie Yang, Yun Lin and Zhaohong Fang
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9 The Secondary Ring-Shaped Pipe Network OptimizationDesign of a District Cooling Project in Chongqing . . . . . . . . . . . . 85Xiaodan Min, Xiangyang Rong, Pengfei Si, Hai Liu and Lijun Shi
10 Factor Analysis for Evaluating Energy-Saving Potentialof Electric-Driven Seawater Source Heat Pump DistrictHeating System Over Boiler House District Heating System. . . . . 93Haiwen Shu, Hongbin Wang, Lin Duanmu and Xiangli Li
11 A Review on Radiant Cooling System in Buildings of China . . . . 101Hongbin Wang, Haiwen Shu and Lin Duanmu
12 Performance Analysis on Energy-Storage HeatTransfer Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109Zhen Tong, Xiaohua Liu, Lun Zhang and Yi Jiang
13 Analysis and Optimization on Solar Energy ChemicalHeat Storage Material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121Qiuhui Yan, Xuedong Zhang and Li Zhang
14 CO2 Heat Pump Water Heater: System Designand Experimental Study . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131Yefeng Liu, Zhiyang Zhuo, Feng Zhang and Tuanwei Bao
15 Design and Analysis on a Kind of Compound RenewableEnergy System for Heating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143Guohui Feng, Mingzhi Jiang, Kailiang Huang,Jialin Sun and Cheng Cheng
16 Operation Regulation of Combined District Heating Systemswith Multiple Large-Scale Peak-Shaving Heat Sources. . . . . . . . . 165Haichao Wang, Wenling Jiao, Chengzhao Jiang,Risto Lahdelma and Pinghua Zou
17 Study on the Energy System of Ice Storage Air Conditioningof China World Trade Center Phase 3 by the Methodof ‘Local-Global Optimization’ . . . . . . . . . . . . . . . . . . . . . . . . . . 175Zonggen Si, Hongqi Li and Yongpeng Shen
18 Experimental Study on Heat Transfer of Pool Boilingand In-tube Condensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183Ming Wang and Yajun Guo
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19 Optimum Design of a Solar-Driven Ejector Cooling System . . . . . 193Wei Zhang, Saffa B. Riffat, Xiaoli Ma and Siddig A. Omer
20 Influence of Intermittent Operation on Soil Temperatureand Energy Storage Duration of Ground-Source HeatPump System for Residential Building . . . . . . . . . . . . . . . . . . . . 203Tao Yu, Zhimei Liu, Guangming Chu and Yunxia Qu
21 China’s Low-Carbon Economy and Regional EnergyEfficiency Index Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215Huifen Zou, Hao Tang, Ying Zhang, Fuhua Yang and Yingchao Fei
Part II HVAC&R Component and System
22 A Flexibility Chilled Beam System in Hot and Humid Climate. . . 227Risto Kosonen
23 Experimental Evaluation of a Total Heat Recovery Unitwith Polymer Membrane Foils . . . . . . . . . . . . . . . . . . . . . . . . . . 235Lei Fang, Shu Yuan and Jinzhe Nie
24 Radiant Floor Behavior in Removing Cooling Loadsfrom Large Glassed Buildings . . . . . . . . . . . . . . . . . . . . . . . . . . . 243Stefano P. Corgnati and Matteo Jarre
25 Influence of Different Temperature Control PatternsThrough TRV on District Heating Loads . . . . . . . . . . . . . . . . . . 251Valentina Monetti, Enrico Fabrizio and Marco Filippi
26 Window Operation and Its Impacts on Thermal Comfortand Energy Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259Liping Wang
27 An Evaluation of Filtration and Air Cleaning EquipmentPerformance in Existing Installations with Regardto Acceptable IAQ Attainment . . . . . . . . . . . . . . . . . . . . . . . . . . 267H. E. Burroughs, Chris Muller, Wenlei Yao and Qingli Yu
28 Variation Law of Aqua Ammonia Falling Film AbsorptionVertically Outside of Transversally Grooved Tube . . . . . . . . . . . 277Xiaozhuan Chen, Wei Sheng, Xiufang Liu, Junjie Chenand Jianhua Liu
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29 Experimental Research on Resistance Characteristicsof Filtering Materials of Biofilter Process of SludgeComposting Plants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 289Gaoju Song, Henggen Shen, Wenjuan Ren, Yonggang Songand Jiaping Zhang
30 Research of Data Center Fresh Air VentilationCooling System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 299Yin Liu, Renbo Guan, Jing Ma and Ke Zhang
31 Design Principle of Air Curtain Ventilation. . . . . . . . . . . . . . . . . 307Haiguo Yin and Angui Li
32 The Comparison of Cooling Performance Between New-TypeCapillary Radiant Panel and Traditional Radiant Panel . . . . . . . 317Jianbo Chen, Haizhao Yu and Gang Liu
33 Analysis on Influence Factors of Lewis Number in a CrossflowReversibly Used Cooling Tower by Experimental Investigation . . . 327Jiasheng Wu, Yanshun Yu, Lin Cao and Guoqiang Zhang
34 Study on Energy Efficiency Evaluation Method of CoolingWater System of Surface Water Source Heat Pump . . . . . . . . . . 333Jibo Long and Siyi Huang
35 Experimental Measurement of Airflow TurbulenceCharacteristics in a Full-Size Aircraft Cabin . . . . . . . . . . . . . . . . 341Chen Shen, Junjie Liu, Wei Wang and Nan Jiang
36 Measurement and Control System of HVAC&R IntegrationTesting Platform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 351Kai Zhang, Xiaosong Zhang, Shuhong Li and Geng Wang
37 Discussion on Testing Method of Ventilation SystemAir Leakage Rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 361Jing Ma, Yin Liu and Renbo Guan
38 Dynamics Characteristics of an Indirect District Heating Systemand Operational Optimization. . . . . . . . . . . . . . . . . . . . . . . . . . . 369Lei Zhao, Jia Wang, Lidong Zhu and Lianzhong Li
39 Simulation on a Two-Stage Compression Heat Pumpwith Focus on Optimum Control. . . . . . . . . . . . . . . . . . . . . . . . . 381Shuang Jiang, Shugang Wang, Xu Jin and Tengfei Zhang
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40 Experimental Analysis of Direct Evaporative Coolingin Special Temperature Range and ExtendedApplication Study . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 399Yao Chen, Yonggao Yin and Xiaosong Zhang
41 Hydraulic and Thermodynamic Condition Analysisof Unidirectional Loop Hot Water Heating System . . . . . . . . . . . 411Shanshan Cao, Yang Yao, Hua Zhao and Huanhuan Li
42 Experimental Study on Measuring the Amount of JetEntrainment by the Tracer Gas Concentration Method . . . . . . . . 421Xin Wang, Youqin Liu and Yuntian Dai
43 Experimental Investigation of Airflow Pattern of FabricAir Dispersion System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 429Xiaoli Wang and Angui Li
44 Dynamic Soil Temperature of Ground-Coupled Heat PumpSystem in Cold Region . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 439Tian You, Wei Wu, Baolong Wang, Wenxing Shi and Xianting Li
45 Study on Heat Transfer of Soil Thermal Recoveryof Ground Source Heat Pump System . . . . . . . . . . . . . . . . . . . . . 449Ping Zhou, Chao Chen, Jinshun Wu, Guixia Hu, Yang Guoand Kang Li
46 Optimized Configuration of Cooling Source in DistrictedCCHP System: A Case Study in Guangxi . . . . . . . . . . . . . . . . . . 461Chundie Li, Jun Lu, Chuck Yu, Xinhui Zhang and Wenzhuo Wang
47 Experimental Study on Performance Comparison Between Heavyand Lightweight Radiant Floor Cooling Combinedwith Underfloor Ventilation Air Conditioning System . . . . . . . . . 475Dongliang Zhang, Ning Cai, Yingxiang Rui, Hu Tangand Minghui Liu
48 Optimization and Energy Efficiency Research of aLarge Reclaimed Water Source Heat Pump System. . . . . . . . . . . 485Ziping Zhang and Fanghui Du
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49 Study on Thermal Storage Performance of Phase Change HeatStorage Type Air Conditioning Cooling Reservoir in CivilAir Defense Engineering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 497Guozhu Li, Guohui Feng, Xiaolong Xu, Na He, Huixing Liand Qizhen Chen
50 Study on Components Match of Solar-Ground Source HeatPump and Heating Network Complementary Heating Systemin Severe Cold Region . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 509Hong Hao, Xiujuan Zhao, Guohui Feng and Xiangyuan Xue
51 Experimental Study on Running Spacing of Buried Pipeand System Heating Performance in GSHP System . . . . . . . . . . . 519Songtao Hu, Bo Lin, Zhigang Shi and Hengjie Yu
52 Electricity Consumption of Pumps in Heat Exchanging Stationsof DH Systems in China . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 527Lei Dong, JianJun Xia and Yi Jiang
53 The Study on Thermal Property of the Rural Traditional KangSurface Within 24 Hours . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 539Qi Feng, Yongan Ao, Lin Duanmu, Zongshan Wang and Feng Qiu
54 Comparison of the Distribution and Concentration of DustParticles by Different Ventilated Systems . . . . . . . . . . . . . . . . . . 551Yang Lv, Bailin Fu, Genta Kurihara and Hiroshi Yoshino
55 Research and Apply on DCS-Based Water-Source Heat PumpSystem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 559Pengfei Si, Xiangyang Rong, Angui Li, Xiaodan Minand Zhengwu Yang
56 Waste Heat Recovery System Using Coal-Fired Boiler Flue Gasto Heat Heating Network Return Water . . . . . . . . . . . . . . . . . . . 567Hua Zhao, Pengfei Dai, Shanshan Cao and Qing Hao
57 District Heating System Adjustment Theoretical Basedon Heat Users’ Real Load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 577Shanshan Cao, Hua Zhao, Xin Xie and Xiaolin Liu
58 Design of Split Evaporative Air Conditioner of EvaporativeCooling and Semiconductor Refrigeration . . . . . . . . . . . . . . . . . . 589Zhe Sun, Xiang Huang and Jiali Liu
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59 Energy-Efficient Heating and Domestic Hot Water SystemsSuitable for Different Regions . . . . . . . . . . . . . . . . . . . . . . . . . . . 601Wei Wu, Baolong Wang, Wenxing Shi and Xianting Li
60 Match Properties of Heat and Mass Transfer Processesin the Internally-Cooled Liquid Desiccant System . . . . . . . . . . . . 609Jingjing Jiang, Xiaohua Liu and Yi Jiang
61 Frosting Characteristics of Fin-Tube Heat Exchangerat Temperature Range of 218 to 6 �C of a Cascade Heat Pump . 619Xing Han, Wei Fan, Jianbo Chen and Qiuhuo Chen
62 Research on the Character of Discharge Temperatureof Air Conditioning System with R32 . . . . . . . . . . . . . . . . . . . . . 635Deyin Zhao, Wenhong Ju, Zhangquan Chen and Xu Zhang
63 Experimental Study of Heat Transfer and Resistanceon Finned Tube Exchanger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 645Yajun Guo, Ming Wang and Guangcai Liu
64 Analytical Thermal Analysis of Novel Foundation Pile GroundHeat Exchanger with Spiral Coils . . . . . . . . . . . . . . . . . . . . . . . . 653Man Yi, Hongxing Yang, Zhaohong Fang and Yunxia Qu
65 The Experimental Analysis of GSHP_RF Heating Systemin Controlled Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 665Weiwei Yin and Qian Zhang
66 Feasibility Analysis of Utilizing the Concrete Pavementas a Seasonal Heat Storage Device for the Ground-CoupledHeat Pump System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 675Yunxia Qu, Houxing Cao and Beiping Jia
67 Retrofit of Air-Conditioning System in Data Center UsingSeparate Heat Pipe System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 685Yuwei Zheng, Zhen Li, Xiaohua Liu, Zhen Tong and Rang Tu
68 The Model for the Separation Efficiency of the ElectrostaticCyclone Dust Collector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 695Jiajun Luo, Hao Zhang, Dong Yang, Jiguang Zhangand Huajun Tang
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69 The Exploration on Heat Transfer Models for Borehole HeatExchanger in the Soil with Groundwater Advection. . . . . . . . . . . 705Lei Zhao, Linlin Zhang and Songtao Hu
70 Numerical Calculation and Analysis of Apply for the HeatTransfer Performance of Porous Brick . . . . . . . . . . . . . . . . . . . . 713Xiaolu Wang, Fuqin Ma and Huifan Zheng
71 Optimized Design of Ground-Source Heat Pump SystemHeat Exchanger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 723Zhigang Shi, Shangping Song and Songtao Hu
72 Positive Investigation on the Reliability of Groundwater SourceHeat Pump System Usage in Yangling Normal Community . . . . . 731Yanzhe Chen, Zhiwei Wang and Zengfeng Yan
73 The Combined Operating of Radiant Floor and Fresh Air Coilin Field Experiment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 741Yanhong Du, Chenggong Qian and Xiangzhao Fu
74 The Complementary Heating Energy Ratio Research of Solar:Ground Source Heat Pump and Heating Networkin Cold Regions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 757Guohui Feng, Jian Zhang, Hong Hao and Yuan Li
75 Investigation and Analysis of the Heat Pump Applicationin Shenyang . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 767Hongwei Wang, Jie Feng, Hui Wang, Guohui Fengand Baoling Wang
76 Experimental Study on Unsteady State Properties of CeilingRadiant Cooling Panels System . . . . . . . . . . . . . . . . . . . . . . . . . . 773Lin Su, Nianping Li, Xuhan Zhang, Yanlin Wu, Yunsheng Jiangand Qing Huang
77 Orthogonal Test and Regression Analysis on FiltrationPerformance of PSA/Needle-Punched PSA Filter Material . . . . . . 781Min Fang, Henggen Shen, Tingting Xue and Libo Wang
78 Research on Condensation Pressure and Temperatureof Heat Pumps Using Blends of CO2 with Butaneand Isobutane. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 791Xianping Zhang, Xiaowei Fan, Xinli Wei, Fang Wangand Xiaojing Zhang
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79 Exergy Analysis of a Ground Source Heat Pump SystemUnder Cooling and Heating Conditions . . . . . . . . . . . . . . . . . . . . 799Lei Zhao and Chen Yuan
80 Ultrasonic Vibration for Instantaneously Removing FrozenWater Droplets from Cold Vertical Surface. . . . . . . . . . . . . . . . . 807Dong Li and Zhenqian Chen
81 Experiment of a New Partitions Filler RegenerationPerformance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 817Lining Zhou, Zhijia Huang, Liping Zhu and Ping Jiang
82 Theoretical Analysis and Numerical Simulation of CoupledRelationship of Heat and Mass Transfer Between Airand Desiccant in Liquid Desiccant Dehumidification . . . . . . . . . . 829Zhijia Huang and Ping Jiang
83 Analysis of the Floor Heat Storage and Release Duringan Intermittent In-Slab Floor Heating Process. . . . . . . . . . . . . . . 841Dengjia Wang, Yanfeng Liu, Yingying Wang and Jiaping Liu
Erratum to: The Study on Thermal Property of the RuralTraditional Kang Surface Within 24 Hours . . . . . . . . . . . . . . . . . . . E1Qi Feng, Yongan Ao, Lin Duanmu, Zongshan Wang and Feng Qiu
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Part IEnergy System
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Chapter 1Net-Zero Energy Technical Shelter
Chen Zhang, Per Kvols Heiselberg and Rasmus Lund Jensen
Abstract Technical shelters are the basic structures for storing electronic andtechnical equipment, and commonly used for telecommunication base station,windmill, gas station, etc. Due to their high internal heat load density and specialoperation schedule, they consume more energy than normal residential or com-mercial buildings. On the other hand, it is a big challenge to power the technicalshelter in remote area where the grids are either not available or the expansion ofgrid is expensive. In order to minimize the energy consumption and obtain areliable and cost-efficient power solution for technical shelter, this study will applythe net-zero energy concept into the technical shelter design. The energy con-servation can be achieved by proper design of building envelop and optimizationof the cooling strategies. Both experiments and numerical simulations are carriedout to investigate the indoor environment and energy performance of the technicalshelter. Finally, a wind-solar hybrid energy system is designed as an alternativepower solution for technical shelter, in order to achieve a net-zero energy target.
Keywords Technical shelter � Net-zero energy � Building envelop � Ventilativecooling � Hybrid energy system
1.1 Introduction
A net-zero energy building is a residential or commercial building with greatlyreduced energy needs through highly efficient building system design whileharvest energy on-site with renewable technologies. Technical shelters as the basic
C. Zhang (&) � P. K. Heiselberg � R. L. JensenDepartment of Civil Engineering, Aalborg University, Sohngaardsholmsvej 57,9000 Aalborg, Denmarke-mail: [email protected]
A. Li et al. (eds.), Proceedings of the 8th International Symposium on Heating,Ventilation and Air Conditioning, Lecture Notes in Electrical Engineering 262,DOI: 10.1007/978-3-642-39581-9_1, � Springer-Verlag Berlin Heidelberg 2014
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structures for storing electronic and technical equipment are commonly used fortelecommunication base station, windmill, gas station, etc. Compared with thenormal residential or commercial buildings, technical shelters consume moreenergy due to their high inner heat density and special operating schedule. Inaddition, powering technical shelter is particularly challenge in remote areas wherethe grids are either not available or the expansion of grid is expensive. A 2,000World Bank/UNDP study on rural electrification programs placed the average costof grid extension per km at between $8,000 and 10,000, rising to around $22,000in difficult terrains [1]. To minimize the energy consumption and provide reliableand cost-effective power solution of technical shelter, it’s promising to apply net-zero energy concept into technical shelter design.
The previous studies show that energy conservation of technical shelter can beachieved by proper design of building envelop and improving the energy perfor-mance of air conditioning system. Nakao et al. [2] presented a thermal control wallcombined exterior wall with cooling system, which can vary its heat transmissioncoefficient from one to ten times that for an ordinary wall and estimated to save20 % of annual cooling energy. Zhang et al. [3] studied energy efficient envelopdesign for telecommunication base station in Guangzhou by considering heattransfer coefficient and solar absorptance. Nakao et al. [4] evaluated the impact ofair flow systems on room air temperature distribution and ambient temperature ofelectric parts in telecommunication equipment rooms. Chen et al. [5] investigatedthe ventilative cooling technology by making full use of natural cooling resource.These studies analyze the impact of single influence factor on the energy perfor-mance of technical shelter. However, there are very rare studies making anexploration by combining these influencing factors, and exploring their impacts indifferent internal heat loads.
An alternative power solution for technical shelter is to use renewable energyresource [6]. Recent researches have shown the great potential of renewable energyto supplement or even replace conventional power systems in some locations wherethe grid is difficult to connect. The white paper [7] presents the state-of-artof sustainable power options, including wind, solar, fuel cell, and Pico hydrotechnologies. An advanced solution is to combine different renewable energysources into a hybrid energy system [8].
The aim of this study is to design a net-zero energy technical shelter byimproving the energy efficient of building systems and finding alternative powersolution for technical shelter. Both experiments and numerical simulation arecarried out to analyze the indoor environment and energy performance of technicalshelter. Finally, an optimal hybrid energy system is design to provide reliable andeconomical power supply to the technical shelter.
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1.2 Performance Investigation by Full-Scale Experiment
1.2.1 Experimental Method
The experiment is made in a full-scale typical technical shelter with the dimensionof 3.82 m length, 2.27 m width, and 2.42 m height. The envelope of the technicalshelter composes of three parts: wall and ceiling, foundation, and door. Wall andceiling are made of sandwich constructions, with a core of expanded polystyreneand painted galvanized steel plate glued to the core. The thickness is 86 mm andU-value is 0.42 W/m2 K. The foundation uses reinforced concrete, with thethickness of 150 mm and the U-value of 3.29 W/m2 K. And the door is D-ratedsteel door with the thickness of 60 mm and U-value of 0.66 W/m2 K. The testedtechnical shelter is located in a workshop, so no climate factor (solar and windfactors) are taken into account. A ventilative cooling system is installed in thetested technical shelter with flexible air intake, which aims to make full use ofnatural outdoor cooling resource. The air flow rate of ventilation system iscontrolled by fan speed, which depended on indoor and outdoor air temperaturedifferent (measured by the temperature sensors located indoor and outdoor).According to Fig. 1.1, the ventilated air supplied into the shelter through the filterbags, and exhausted by the blinded opening located in the upper zone of theshelter.
The aim of the experiment is to investigate the indoor environment and energyperformance of the tested technical shelter in different internal heat load condi-tions. Thus, two heat load conditions are analyzed in the experiment: 1.5 and3 kW. The indoor environment is evaluated by the vertical temperature profile,where air temperatures are measured in the middle of shelter in six differentheights: 0.1, 0.5, 1.0, 1.5, 2.0, and 2.3 m, respectively, Fig. 1.2. In addition, supplyand exhaust air temperatures as well as the ambient air temperature are measuredin order to estimate the energy performance of technical shelter. All temperaturesare measured by K-type thermocouples and recorded by data logger.
Fig. 1.1 Schema of thetechnical shelter andpositions of tracer gas sensors
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The ventilation rate is measured by tracer gas technique. The constant injectionmethod is used, where the equilibrium tracer concentration within a ventilated areais measured and this concentration can be related to the ventilation rate if the tracerrelease rate is known [9]. With regard to ventilation system, the pressure rise of thesystem is measured by a manometer and the electric power is measured by an ACpower Analyzer.
1.2.2 Experimental Results
1.2.2.1 Performance of Ventilative Cooling System
In the ventilative cooling system, the cooling capacity is varied by changing airflow rate (VAV) and is controlled by fan’s speed. The fan efficiency curve gives aclear indication of the energy performance of the ventilative cooling system, whichis the ratio between power transferred to the air flow and the power consumed bythe system. It is expressed by Eq. (1.1).
g ¼ DP � qE
ð1:1Þ
where g is energy efficiency, DP is pressure rise across the fan (Pa), q is airflowrate (m3/s), and E is electric power (W).
Figure 1.3 shows the fan efficiency curve of the tested ventilative cooling systemas a function of air flow rate. The efficiency significantly increases with increasedthe airflow rate and reaches a peak efficiency of 78.95 % when the airflow rate isaround 0.3 m3/s. After that, efficiency gradually decreases with increased airflowrate until the airflow rate reaches the maximum value. It needs to notice that evenwhen the airflow rate is zero, electric power of tested system is almost 13 W, whichmeans that is quite inefficient to operate the system in this condition.
Fig. 1.2 a Plan view of technical shelter and positions of thermocouples; b cross-section oftechnical shelter and positions of thermocouples
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1.2.2.2 Temperature Gradient
In this experiment, in order to keep the average indoor temperature around 30 �C,the ventilation system are running at 0.092 and 0.22 m3/s air flow rate for 1.5 and3 kW cases, respectively. Figure 1.4 shows the vertical temperature profiles forthese two cases. In 1.5 kW case, the air temperature is almost constant from 0.1 to1.0 m height, after that the temperature increases significantly with the height.This is because the heat source (1.5 kW) is too weak to generate great convectionflow which causes completely mixing between cold supply air and the warm spaceair. So that high density cold air is trapped at the lower zone. On the contrary, in3 kW case, the temperature linear increases with height at the lower zone while nolarge gradient from 1.5 to 2.3 m. This may be caused by the higher air flow rategenerate higher supply air velocity, which enhances the turbulence level closed tosupplied zone. However, in both of cases, the temperature gradient is large and thetemperature difference reaches more than 10 �C between floor and ceiling level.This fact will be good for reducing the cooling need if the electric equipments arelocated at the lower zone. Even though the temperatures at the higher zone haveexceeded the set point temperatures, the temperatures at the lower zone are still inan acceptable level. In addition, the period for people to stay in technical shelterfor maintenance is very limited, so the discomfort caused by temperature gradientcan be ignored in practice.
Fig. 1.3 Measured fanefficiency curve of theventilative cooling system
Fig. 1.4 Measured verticaltemperature profiles for 1.5and 3 kW cases
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1.2.2.3 Energy Balance of the Technical Shelter
Generally, there are five heat sources or heat sinks in the technical shelter using aventilative cooling system (Fig. 1.5): equipment heat load (Qeq), heat transmissionthrough envelops (Qtrans), infiltration (Qinf), heat removed by ventilative coolingsystem (Qvent), and solar radiation (Qsun). Thus, the energy balance in the sheltercan be expressed by Eq. (1.2).
Qeq þ Qtrans þ Qvent þ Qinf þ Qsun ¼ 0 ð1:2Þ
Heat transmission through the building envelop can be expressed by theEq. (1.3):
Qtrans ¼ U � A � ðTin � ToutÞ ð1:3Þ
where U is the heat transfer coefficient of building envelop W/(m2 K), A is the areaof building envelop (m2), Tin and Tout are indoor and outdoor air temperature (�C).Heat removed by ventilative cooling system has the definition below:
Qvent ¼ Cp � q � q � Tex � Tsup
� �ð1:4Þ
where Cp is specific heat capacity of air (kJ/kg K), q is density of air (kg/m3), q isairflow rate (m3/s), Tex and Tsup is exhaust and supply air temperature (�C).
However, the tested technical shelter is located in a workshop in this experi-ment, where no solar radiation is available and the temperature in the workshopkeeps constant during measurement. Thus, the solar heat gain will be regardless in
Fig. 1.5 Heat sources or heat sinks in the technical shelter
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this case. In addition, the technical shelter are designed to be well sealed, thus theinfiltration loss can be ignored if compared with the amount of ventilation.
In the measurement, two radiators serve as equipments to dissipate heat into theshelter. The powers of these two radiators are 1.52 and 1.59 kW, respectively. Theoutdoor temperature is kept around 19 �C during the measurement, and averageindoor temperature is around 30 �C for both cases.
The contribution of each heat sources or heat sinks can be shown clearly inFig. 1.6. Without any solar radiation, the electric equipment heat load (includingthe heat dissipation from the fan) is the only heat gain in our cases. Heat trans-mission through envelop and ventilative cooling are the main ways to remove heatfrom inside shelter. As indicated in Fig. 1.6, the calculated results by the simplifiedanalysis method accord well with the energy balance, where the deviations of 1.5and 3 kW cases are 13 and 2 %, respectively. This means no other unknown heatsources or heat sinks influence the energy performance of technical shelter. Thus,in order to reduce the energy consumption of technical shelter, it’s important toperform energy efficiency envelops design and optimizes the control of ventilationsystem.
1.3 Performance Optimization by Numerical Simulation
1.3.1 Simulation Method
The aim of the numerical study is to evaluate the energy saving potential of thetechnical shelter by proper design of building envelope and application of anoptimal ventilative and mechanical cooling strategy. The evaluation of the energysaving potential is carried out using a building thermal and energy simulationprogram. In this case, the BSim software is adopted to simulate the annual energyperformance and indoor environment of a standard technical shelter [10].
The model created in BSim accords to the real plan of a standard technicalshelter. The climate data of Copenhagen is used in the simulation based on the
Fig. 1.6 Contribution ofeach heat sources or heatsinks
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Danish design reference year. And it is assumed that there are no other buildings inthe neighborhood, thus no shadow from surroundings. Three equipment heat loadsare analyzed: 1.5, 3, and 5 kW. In order to explore the optimal envelope solution,wall and ceiling are simulated with different insulation thicknesses. Four insulationthickness conditions are taken into account: 25, 50, 85, and 100 mm, and thecorresponding U-values are 1.45, 0.72, 0.42, and 0.36 W/m2 K, respectively. Theset point temperature for cooling operation is 30 �C, while the set point temper-ature for heating operation is 10 �C. The cooling system composes of two parts:ventilative cooling system and an air-conditioner. The parameters of ventilativecooling system are set up according to the measurement results. The COP of the airconditioner is assumed to be 3 in this study.
1.3.2 Simulation Results
1.3.2.1 Impact of Envelope Insulation
Figure 1.7 shows the relationship between annual energy demand (heating/cooling) of the technical shelter and insulation thickness under three heat loadconditions. For a normal building construction (office or residential building), thebetter insulation normally means higher energy saving potential. However, thisconcept is not applicable to technical shelter due to its high inner heat load density.As indicated in Fig. 1.7, the annual energy demand linearly rises while increasinginsulation thickness. In addition, the simulation results show that cooling is thedominant energy demand in all cases. Heating is only needed in the case of 1.5 kWheat load with 25 mm insulation. However, the amount of the heating demand(27 kWh) can be ignored if compared with that of cooling (2,580 kWh), whichtaken only 1 % of total energy demand. Finally, as could be expected, the higherthe heat load the more energy is needed.
The energy performance of the technical shelter and the contribution ofdifferent heat sources are also explored in four typical cases. The equipment runscontinuously with a certain heat load, thus, the heat gain from equipment keeps
Fig. 1.7 Annual energy demands in different envelope insulation conditions. a 1.5 kW, b 3 kW,c 5 kW
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constant during the whole year. The solar heat gain mainly depends on the solarradiation intensity, which has significant fluctuation between day and night. Inmost of the time, the envelope heat transmission help to dissipate the surplus heatload out of the shelter. The envelope with lower insulation thickness can transfermore heat to the outdoor environment, which is beneficial for reducing coolingdemand. However, this will in return enhance the heating need potential in winter.As indicated in Fig. 1.8a, when the internal heat load is lower (1.5 kW), theenvelop transmission not only remove all the heat load from the shelter in winterbut also cause some heating demand when the indoor temperature is lower than10 �C. On the other hand, in summer when the outdoor temperature is higher thanindoor temperature, the envelop transmission will become heat gain whichaggravates the cooling demand. During this period, the technical shelter withhigher insulation thickness has better performance on preventing transmission heatgain, as indicated in Fig. 1.8b. For the technical shelter with higher internal heatload 5 kW, Fig. 1.8c, d, no heating is needed during the whole year. The envelopewith higher insulation thickness 85 mm significantly reduces transmission loss andtherefor increases the annual cooling demand.
Fig. 1.8 Energy performance of the technical shelter with different internal heat loads andenvelop insulation thicknesses. a 1.5 kW, 25 mm; b 1.5 kW, 85 mm; c 5 kW, 25 mm; d 5 kW,85 mm
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1.3.2.2 Cooling Strategies
If the ventilative cooling system can make full use of natural cooling resource ofoutdoor air, it can significantly reduce the cooling demand of the technical shelter.Normally, ventilation system consists of two types: natural ventilation andmechanical ventilation. Natural ventilation can be achieved by opening windowsor doors to allow fresh cold air into the building. However, the technical shelter asa special building is normally designed without any window, and for the safetyreasons, the door need to be closed during the whole year. Thus, the ventilationalways achieved by applying a fan and the air change rate can be varied to meetthe rising and falling heating gains or losses within the shelter.
The relationship between air change rate and annual cooling demand is ana-lyzed by two cases: 85 mm, 1.5 kW and 85 mm, 5 kW. Figure 1.9 indicates thatcooling demand can be significantly reduced by increasing air change rate. Whenthe air change increases to 20 h-1 in 1.5 kW case and 50 h-1 in 5 kW case, thereduction of annual cooling demand reaches 90 % in both cases. After that,although air change rate continuous increases, the annual cooling load does notreduce significantly.
Controlling the indoor temperature in a safety range is very important forobtaining high performance and reliable operation of equipment. Thus, it’s nec-essary to explore the effect of air change rate on indoor environment. Overheatinghour is chosen as a key parameter to analyze how much time the indoor tem-perature exceeds set point temperature. As shown in Fig. 1.10a, c, overheatingmainly occurs during summer season from May to September and reaches a peakin July. This is because ventilation cooling uses outdoor air as cooling sources,which greatly depend on the outdoor temperature and easily influenced by climate.As mentioned, when the air change rate reach 20 and 50 h-1 in 1.5 and 5 kW case,respectively, more than 90 % heat load can be eliminated. But the overheatinghours still reach 500 and 1000 h in these situations, respectively. Even increasingair change rate to 100 and 150 h-1, the overheating phenomenon cannot entirelydisappear, because ventilative cooling does not work when the outdoor
Fig. 1.9 Relationship between air change rate and annual cooling demand. a 85 mm, 1.5 kW;b 85 mm, 5 kW
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temperature is higher than set point indoor temperature. Thus, it needs to cooperatewith air conditioner to achieve the cooling target in this condition.
Figure 1.10b, d indicate the amounts of overheating hours in each temperaturerange. It’s clear to find out that the overheating temperature is mainly in the rangeof 30–35 �C. The higher the ventilation rate, the less the overheating hour will be.The overheating temperature above 45 �C only last 10–20 h per year when theventilation rate is 10 and 40 h-1 in 1.5 and 5 kW cases, respectively. And in otherventilation rate, overheating temperature is almost below 40 �C. Thus, it isessential to find out the temperature sensitivity of electric equipment in thetechnical shelter. The ventilation rate can be greatly reduced if the equipment canstill work in the overheating condition for a certain period, so is the energyconsumption of ventilation system. If the indoor temperature exceeds the per-mitted temperature of electric equipment for a long time, air-conditioner needs towork together with ventilative cooling system to discharge the internal heat,especially in the summer time.
As indicated in Fig. 1.9, an appropriate ventilation rate can meet the coolingdemand in most time of the year. However, during summer, when the outdoortemperature increase, only increasing ventilation rate cannot achieve the target toremove all heat or it need huge ventilation rate to do so. Thus, another cooling
Fig. 1.10 Overheating hours for different ventilation rates. a Overheating hours per month,85 mm, 1.5 kW; b overheating hours distribution of indoor temperature, 85 mm, 1.5 kW;c overheating hours per month, 85 mm, 5 kW; d overheating hours distribution of indoortemperature, 85 mm, 5 kW
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