T. Kurabuchi, T. Ogasawara, H. Ochiai and S. Lee
Bibliographic info:
The International Journal of Ventilation, Vol. 12 N°2, September 2013

The National Museum of Western Art is the only work of Le Corbusier in Japan and 50 years have already passed since its construction. In order to maintain the museum’s value as a cultural asset, there is an urgent need to draft a thorough retrofit plan both to maintain the building’s function as an art museum and to restore Le Corbusier’s original design concept.

This study, which carried out an indoor environmental investigation for the purpose of developing such a retrofit plan in the main building, confirms the current airflow characteristics on the basis of a survey of factors such as the flow rates of the air conditioning system, internal pressures, and the age of air distribution. Because the exhaust flow rate was greater than the supply of fresh air into the building, there was concern about air infiltration. It was found that the age of air was highest in the exhibition space, comparatively lower in the entrance hall, and lowest in the restaurant. The adjacent wall air velocities varied greatly according to the locations and the highest values were around 0.7 m/s.

In order to separate the exhibition space from the entrance hall to avoid possible disturbance from outdoors, glass partitions that were not part of Le Corbusier’s original design were added after the building was completed. CFD predictions were carried out to evaluate the air environment under the conditions of the original design using variable air conditioning zoning plans. Analysis indicated that if the original design were restored, using the present air conditioning zoning, there would be an increased risk of moisture condensation on the glass surface of the entrance hall. It was concluded, however, that this risk would be significantly reduced by subdividing the air conditioning zone and changing the air conditioning controls in each subdivided area.