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School of Civil Engineering
Integrating Heat Transfer Devices Into Wind Tower Systems to provide Thermal Comfort in Residential Buildings
John Kaiser S. CalautitSupervisors: Dr. B. Hughes and Prof. N. Wright3rd CFD Group Meeting
School of Civil Engineering
John Kaiser S. Calautit
Wind Tower – Natural Ventilation Device
Stale Air Out
Fresh Air In
(Micro Climate)
- Leeward
+ Windward
(Macro Climate)((
(Macro Climate)((
• • Originated from the Middle East (hot and arid regions).
• Incorporated with advance technology (control dampers, ceiling diffusers , solar panels)
Traditional Architecture Commercialized Re-Engineering
• Bring the technology back to the Middle East using heat transfer devices powered system.
Buoyancy and displacement effect (driving forces)
Windward (+) Leeward (-)
School of Civil Engineering
Looking into Wind Tower Systems – Airflow Analysis
• Supplies airflow at ceiling level
• Increased the indoor airflow by up to 60%
• Two 4-sided wind tower system (2 floor residential building)
• Average indoor airflow of 0.4 m/s
John Kaiser S. Calautit
School of Civil Engineering
Traditional Evaporative Cooling (Controlled Test): Existing Cooling Technology
0 1 2 3 4 5 6 7 8 9 10293295297299301303305307309311
Evaporative cooling
Position (m)
Stat
ic T
empe
ratu
re (k
)
Disadvantages:
1. Water - scarce
2. Pump – continuous power supply
3. High Tower – not feasible in urban areas
297 K
Wind Tower Channel with Evaporative Cooling (Published Data)
310K
297 K
John Kaiser S. Calautit
Inlet310K
Outlet
Injected Water 0.05 kg/s, 293K
School of Civil Engineering
John Kaiser S. Calautit
Top Hat
Adjustable Dampers
Louver
1. Integrate heat transfer devices into a commercial wind tower system for the Middle East.
Aims and Objective:
Evaporator
Condenser
Heat exchanger system
School of Civil Engineering
John Kaiser S. Calautit
2. Optimize the thermal comfort of a Qatari residence using the proposed wind tower system. Predicting thermal comfort using PMV model software.
0 5 10 15 20 2505
1015202530354045
Summer - June
InsideOutside
Time (Hour)
Tem
per
atu
re (
C°)
35 C°
Predict Thermal Comfort
•Required Indoor Temperature?•Required Indoor Velocity?
Hottest Month
School of Civil Engineering
John Kaiser S. Calautit
Challenges:
1. Reduce the indoor temperature by 10-12K to achieve thermal comfort during summer periods.
2. Achieve minimal restriction in the external air flow stream while ensuring maximum contact time. Supply up to 400 L/s
3. Compact Design - Fit the heat transfer devices and cool sink inside wind tower.
4. Cool Sink
5. Dust
School of Civil Engineering
John Kaiser S. Calautit
CFD Results : Airflow Analysis – Louver Angle (Components)
2.55 m/s
3.31m/s
45˚ 35˚
Reduced Air CirculationHigh Air Circulation
1 m/s 1 m/sUnavoidable due to the louvers and 90˚ bend
School of Civil Engineering
John Kaiser S. Calautit
Research Output: Publications
• B R Hughes, J K Calautit, S A Ghani, The development of commercial wind towers for natural ventilation: A review, Applied Energy, 92, 606-627, 2012
• J K Calautit, B R Hughes, S A Ghani, A Numerical Investigation into the Feasibility of Integrating Green Building Technologies into Row Houses in the Middle East, Architectural Science Review, 55, 1-18, 2012.
Future Work:
• CFD (Transient Modeling, UDF, Solar Loading, Dynamic Mesh)
• Experimental Work (Wind Tunnel Design, Scaled-Model Testing)
• Qatar Visit (Duct Testing and Full Scale Testing)