Innovative Design Concept for the New Bangkok International Airport, NBIA Wolfgang KESSLING, Stefan HOLST, Matthias SCHULER Transsolar Energietechnik, Munich, Germany
ABSTRACT Thermal and visual comfort for the occupants of a room are not defined by air temperature only, but also radiation with its three components solar radiation, daylight and heat radiation has to be taken into account (among other factors such as humidity, air speed and occupant activity and clothing levels). In hot climates the optimization of room comfort is a challenging task due to the high solar radiation over the whole year. In intelligent buildings new material developments are applied optimizing the building envelope in an integral building design process. New solutions for weather, noise and heat protection are developed, where building envelope and installed mechanical equipment work together creating optimal comfort at minimum energy consumption. This approach was used in the design of the New Bangkok International Airport, NBIA to develop an optimized building concept in a design team comprising the architects, structural and mechanical engineers, HVAC, acoustic and climate engineers.
the desired indoor climate conditions of 24 °C room temperature and 50 to 60 % relative humidity call for permanent cooling and dehumidification within the building and a sophisticated concept for the envelope to minimize the effects of the external solar loads. CONCEPT DEVELOPMENT This approach was used in the design of the New Bangkok International Airport, to develop an optimized building concept in a design team comprising the architects, structural and mechanical engineers, HVAC, acoustic and climate engineers. For the terminal building of the NBIA with a length of 440 m and a width of 110 m the technique of shading by large overhangs was applied, but at the same time a roof created that allows daylight to pass through. Large external trellis blades that face to the south and open up to the north provide effective shading for direct sunlight allowing diffuse indirect light from the sky to enter the building. Proper daylighting levels for the terminal hall and views through the roof to the sky in combination with sun protection are achieved. The shading trellis blades are naturally ventilated and located outside the building envelope, so their absorbed solar heat does not enter the building.
Figure 1 Model of the terminal and concourse buildings BOUNDARY CONDITIONS In Bangkok, the climate is characterized by temperatures of 25 to 35 °C and a high level of relative humidity all the year round. The annual horizontal solar radiation total is more than 1,500 kWh/m²a and results in a solar radiation of 1,000 W/m² on many days of the year with solar altitudes near the zenith. The situation of an international airport with 24hours working days and high internal heat loads from people, electric equipment and lighting combined with
Figure 2 Model of the New International Bangkok Airport In this case the separation of weather and sun protection layers leads to an optimized result as a starting situation for the air conditioning in the terminal hall, because most of the solar radiation is prevented from entering the terminal hall. 1/9
TRANSSOLAR Energietechnik GmbH, Goethestrasse 28, D-80336 Munich, Germany
Air conditioning of large volume enclosures with internal building elements creates a high cooling demand in relation to the actually occupied space. In the case of the NBIA the total volume of the building is split into unconditioned zones at higher levels and cooled occupied zones at low levels drastically reducing the total cooling demand because mechanical cooling is applied only in spaces where it is actually needed. Two different mechanical systems for cooling are used. First there is a radiant floor cooling directly removing solar and heat...