Go to ScienceDirect® Home Skip Main Navigation Links
 Register or Login:   Password:  
   
   
HomeSearchBrowse JournalsBrowse Book Series, Handbooks and Reference WorksBrowse Abstract DatabasesMy ProfileAlerts Help (Opens New Window)
 Quick Search:   within  Quick Search searches abstracts, titles, keywords, and authors. Click here for more information.  
Results List Previous  2 of 15  Next
Building and Environment
Volume 40, Issue 9 , September 2005, Pages 1164-1173

This Document
SummaryPlus
Full Text + Links
PDF (756 K)
External Links
SFX Context Sensitive Linking
Actions
Cited By
Save as Citation Alert
E-mail Article
Export Citation

doi:10.1016/j.buildenv.2004.11.006    How to Cite or Link Using DOI (Opens New Window)  
Copyright © 2004 Elsevier Ltd All rights reserved.

A feasibility study of a ventilated beam system in the hot and humid climate: a case-study approach

Risto Kosonena, Corresponding Author Contact Information, E-mail The Corresponding Author and Freddie Tanb

aHalton Oy, Haltonintie 1-3, 47400 Kausala, Finland
bCapitaLand Commercial Ltd., 39 Robinson Road, Singapore 068911, Singapore

Received 26 May 2003;  accepted 2 November 2004.  Available online 19 December 2004.


Abstract

The applications of ventilated beam systems in the hot and humid climate are limited. The main reason is the high risk of condensation. A case-study measurement was conducted in a typical office building in Singapore to investigate the feasibility of a ventilated beam system in the Tropics. The results show that the condensation in the beam system is possible to prevent and to reach dry cooling if infiltration is minimized, supply airflow rate is sufficient to extract humidity of people and tuning of the automation system has conducted probably.

Keywords: Ventilated beams; Air–water systems; Humidity control; Hot and humid climate


Article Outline

1. Introduction
2. Review of air–water systems
3. Experimental work
3.1. The ventilated beam office
3.2. Ventilated beam system and measurement
3.3. Description of a reference building
4. Results
4.1. Measurements in a ventilated beam office
4.2. Measurements in a reference building
5. Discussion
6. Conclusions
Acknowledgements
References



Enlarge Image
(105K)
Fig. 1. The window structure of the ventilated beam office.

Enlarge Image
(175K)
Fig. 2. The office layout and the locations of the ventilated beam office and conference rooms.

Enlarge Image
(10K)
Fig. 3. The ventilated beam installation in a conference room.

Enlarge Image
(9K)
Fig. 4. The ventilated beam installation in an office room.

Enlarge Image
(6K)
Fig. 5. In a ventilated beam, the supplied air from nozzles induces room air and the total supply air is introduced through longitudinal slots into the room space.

Enlarge Image
(24K)
Fig. 6. The concept of the ventilated beam system and the measurement points in the case-study building.

Enlarge Image
(64K)
Fig. 7. The operation conditions in the ventilated beam system during one typical working day.

Enlarge Image
(106K)
Fig. 8. The operation temperatures in the ventilated beam system and the conditions in the conference room, the office and outdoor air during 6 days.

Enlarge Image
(38K)
Fig. 9. The measured humidity ratio in the ventilated beam office and in a surrounding office that is served by mixing system.

Enlarge Image
(192K)
Fig. 10. The temperature and humidity in the one person's room, the open layout office and outside air during 3 days in a reference mixing ventilated office building. The third day is saturday.

Enlarge Image
(36K)
Fig. 11. Dew point as a function of airflow rate with different activity level of a person. The room temperature is 23 °C and the supply air temperature is 14 °C (humidity ratio of 10.1 g/kg).


Table 1.
The design conditions of the ventilated beam system in the case-study office
Design conditions Conference room Office
Indoor temperature (°C) 23 23
Relative humidity (%) 60 60
Room area (m2) 56 20
Sensible load (W) 2360 1780
Specific load (W/m2) 42 89
Number of persons 20 3
Off-coil temperature (°C) 14 14
Air flow rate (l/s) 147 56
Water inlet (°C) 16 16
Water outlet (°C) 18 18

Table 2.
Measurement instruments and accuracy
Parameter Instrument Accuracy
Water inlet and outlet temperature Type T thermocouple wire Click to view the MathML source
Room air relative humidity Portable data logger ±5% RH
Room air drybulb temperature Portable data logger Click to view the MathML source

Table 3.
Dew point temperature as a function of the target room temperature and relative humidity
Relative humidity (%) Temperature ( °C)
23 24
60 14.8 15.8
65 16.1 17.0
70 17.2 18.2


References

[1] Wargocki P, Wyon DP, Baik YK, Clausen G, Fanger PO. Perceived air quality, SBS-symptoms and productivity in an office at two pollution loads. The eighth international conference on indoor air quality and climate, Edinburgh, Scotland.

[2] Wyon DP. Individual microclimate control: required range, probable benefits and current feasibility. In: Proceedings of indoor air ’96. Institute of Public Health, Tokyo.

[3] Hagström K, Kosonen R, Heinonen J, Laine T. Economic value of high quality indoor air quality. Proceedings of healthy building 2000 conference. August 6–10, Espoo.

[4] L. Fang, G. Clausen and P.O. Fanger, Temperature and humidity important factors for perception of air quality and for ventilation requirements, ASHREA Transactions 2 (2000), pp. 503–510. Abstract-Compendex  

[5] Laine T, Kosonen R, Horttanainen P, Laitinen A. LCC comparison of air-conditioning systems. Indoor air ’99. Edinburgh, Scotland 8–13.8.1999. The eighth international conference on indoor air quality and climate. p. 602–3.

[6] A. Novoselac and J. Srebric, A critical review on the performance and design of combined cooled ceiling and displacement ventilation system, Building and Environment 34 (2002), pp. 497–509. SummaryPlus | Full Text + Links | PDF (464 K)

[7] J. Frediksson, M. Sandberg and B. Moshfegh, Experimental investigation of the velocity field and airflow pattern generated by cooling ceiling beams, Building and Environment 36 (2001), pp. 891–899.

[8] Wilkins C, Kosonen R. Cool ceiling system: a European air-conditioning alternative. ASHRAE Journal 1992; 41–5.

[9] B.B.P. Lim, Control of the external environment of buildings. In: K.R. Rao, Editor, Solar radiation and external temperatures of buildings, Singapore University Press, Singapore (1988), pp. 19–43 [Chapter 5].

[10] S.E.G. Jayamaha, N.E. Wijeysundera and S.K. Chou, Effect of rain on the heat gain through building walls in tropical climates, Building and Environment 32 (1997), pp. 465–477. SummaryPlus | Full Text + Links | PDF (1330 K)

[11] L.Z. Zhang and J.L. Niu, Indoor humidity behaviors associated with decoupled cooling in hot and humid climates, Building and Environment 38 (2003), pp. 99–107. SummaryPlus | Full Text + Links | PDF (284 K)

[12] M.D. Lyberg, Basic air infiltration, Building and Environment 32 (1997), pp. 95–100. SummaryPlus | Full Text + Links | PDF (676 K)

[13] van der Haas J. Air flow through large openings in buildings. Technical Report from Annex 20. International Energy Agency, Swiss Federal Institute of Technology; 1992.

[14] T. Kusuda, Indoor humidity calculation, ASHREA Transactions 89 (1983) (2), pp. 728–738.

[15] Y. Chen and Z. Chen, Transfer function method to calculate moisture adsorption and desorption in buildings, Building and Environment 33 (1998), pp. 201–207. SummaryPlus | Full Text + Links | PDF (646 K)

[16] Ministry of the Environment. Guidelines for good indoor air quality in office premises. Singapore: 1996.

[17] ASHRAE. Standard 55a–Addendum to thermal environmental conditions for human occupancy. 1995.

[18] Yu WJ, Cheong KWD, Kosonen R, Xie YH, Leow HC. A thermal comfort study on displacement ventilation in the tropics. Healthy building 2003 conference, Singapore, submitted to the conference.

[19] Xie YH, Cheong KWD, Kosonen R, Yu WJ, Leow HC. Indoor air quality on displacement ventilation in the tropics. Healthy building 2003 conference, Singapore, submitted to the conference.

[20] H. Viitanen, Modelling the time factor in the development of mould fungi in wood—the effect of critical humidity and temperature conditions, Holzforschung 51 (1997) (1), pp. 6–14.

[21] ASHRAE. Pocket Guide for Air Conditioning, Heating, ventilation and Refrigeration (SI units). American Society of Heating, Refrigerating and Air-Conditioning Engineers, INC, Atlanta, GA, USA, 1997.

[22] P.O. Fanger, Thermal comfort, McGraw-Hill Book Company, New York (1972).



Corresponding Author Contact InformationCorresponding author. Tel.: +358 40 5027484; fax: +358 5 740 25 00.


This Document
SummaryPlus
Full Text + Links
PDF (756 K)
External Links
SFX Context Sensitive Linking
Actions
Cited By
Save as Citation Alert
E-mail Article
Export Citation
Building and Environment
Volume 40, Issue 9 , September 2005, Pages 1164-1173


Results List Previous  2 of 15  Next
HomeSearchBrowse JournalsBrowse Book Series, Handbooks and Reference WorksBrowse Abstract DatabasesMy ProfileAlerts Help (Opens New Window)

Feedback  |  Terms & Conditions  |  Privacy Policy

Copyright © 2005 Elsevier B.V. All rights reserved. ScienceDirect® is a registered trademark of Elsevier B.V.