Indoor thermal comfort research on the hybrid system of radiant cooling and dedicated outdoor air system

Abstract

The radiant cooling system generally operates with the dedicated outdoor air system (DOAS). Air supply modes and the corresponding setting parameters of the hybrid system may substantially influence the indoor thermal comfort. With target indexes of air diffusion performance index (ADPI) and predicted mean vote (PMV), the Taguchi method was used to choose the optimal air supply mode and to analyze the significance of different factors on the thermal comfort. The results are expected for conducting the future design and regulation of the hybrid system. Computation fluid dynamics (CFD) simulation as well as verified experiments was performed during the research. Based on the ADPI studies, it is found that the air supply mode of ceiling delivery with ceiling exhaust is an optimized option to apply in DOAS of the hybrid system. Variance analysis results show that influence fact of air supply temperature is the most dominant one to impact the indoor thermal comfort index of PMV.

Keywords

radiant cooling system / dedicated outdoor air system (DOAS) / thermal comfort / Taguchi method / variance analysis

References

[1] Feustel H E, Stetiu C. Hydronic radiant cooling-preliminary assessment. Energy and Building, 1995, 22(3): 193–205

[2] Tian Z, Ding Y, Wang S, Yin X L, Wang M L. Influence of the ventilation system on thermal comfort of the chilled panel system in heating mode. Energy and Building, 2010, 42(12): 2360–2364

[3] Hodder S G, Loveday D L, Parsons K C, Taki A H. Thermal comfort in chilled ceiling and displacement ventilation environments: Vertical radiant temperature asymmetry effects. Energy and Building, 1998, 27(2): 167–173

[4] Kitagawa K, Komoda N, Hayano H, Tanabe S. Effect of humidity and small air movement on thermal comfort under a radiant cooling ceiling by subjective experiments. Energy and Building, 1999, 30(2): 185–193

[5] Catalina T, Virgone J, Kuznik F. Evaluation of thermal comfort using combined CFD and experimentation study in a test room equipped with a cooling ceiling. Building and Environment, 2009, 44(8): 1740–1750

[6] Chiang W H, Wang C Y, Huang J S. Evaluation of cooling ceiling and mechanical ventilation systems on thermal comfort using CFD study in an office for subtropical region. Building and Environment, 2011, 48(1): 113–127

[7] Corgnati S P, Perino M, Fracastoro G V, Nielsen P V. Experimental and numerical analysis of air and radiant cooling systems in offices. Building and Environment, 2009, 44(4): 801–806

[8] Zang X G, Zhao S X, Li W J. On comparison and analysis of thermal comfort with application of ADPI and PMV evaluations. Shanxi Architecture, 2010, 36(33): 174–175

[9] Ng K C, Kadirgama K, Ng E Y K. Response surface models for CFD predictions of air diffusion performance index in a displacement ventilated office. Energy and Building, 2008, 40(5): 774–781

[10] Abu-El-Hassan M B, Hosni M H, Miller P L. Evaluation of turbulence effect on air distribution performance index (ADPI). ASHRAE Transactions, 1996, 102: 322–331

[11] Loveday D L, Parsons K C, Taki A H, Hodder S G. Displacement ventilation environments with chilled ceiling: Thermal comfort design within the context of the BS EN ISO7730 versus adaptive debate. Energy and Building, 2002, 34(6): 573–579

[12] Chen Q Y, Xu W R. A zero-equation turbulence model for indoor airflow simulation. Energy and buildings, 1998, 28(2): 137–144

[13] Zhao B, Li X T, Yan Q S. Simulation of indoor air flow in ventilated room by zero-equation turbulence model. Journal of Tsinghua University (Science & Technology), 2001, 41(10): 109–113

[14] Zhao B, Li X T, Yan Q S. Simplified method for numerical simulation of indoor airflow. HV&AC, 2003, 33(3): 102–104

[15] Turgut E, Cakmak G, Yıldız C. Optimization of the concentric heat exchanger with injector turbulators by Taguchi method. Energy Conversion and Management, 2012, 53(1): 268–275

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2014 Higher Education Press and Springer-Verlag Berlin Heidelberg