By Fan Jiayuan, Li Yanfei, People’s Daily
China’s National Aquatics Center, also known as the “Water Cube,” showcased its powerful technology of temperature control during an ice sports testing program titled “Experience Beijing” launched from April 1 to 10.
As the world’s first sports venue that is able to turn its swimming pool into an ice rink, the “Water Cube” will be transformed into an “Ice Cube” during the Beijing 2022 Winter Olympics and Paralympics, serving as the venue for curling events and wheelchair curling events.
The “Water Cube” is the largest Olympic natatorium and the largest membrane structure building in the world, as well as the world’s first polyhedron steel structure. Now, it is crowned with new titles such as the world’s first Olympic and Paralympic venue that establishes curling lanes above a swimming pool, and the world’s first sports venue that can run ice and aquatic events simultaneously.
To turn the “Water Cube” into an “Ice Cube” is not as easy as making ice on the ground. The transition takes five procedures, including pumping the water, setting up steel frames and mounting plates, paving the insulating layer and waterproof layer, installing a removable ice making system and glaciating the water with refrigerating medium, said Hou Bencai, vice general manager of China Construction First Group Construction and Development Co., Ltd.
Precision control is the most difficult part of the process, he introduced. Curling events have a very high requirement on the flatness of the ice. The deformation of the support structure shall be less than 1 millimeter under a pressure of 150kg per square meter.
Besides, it is also hard to realize the complicated temperature and humidity stratification. Aquatic events are held in an environment with high temperature and humidity, while it is the other way around for ice sports.
Curling events have even stricter requirements on environment, during which the temperature must be kept in three different zones. The temperature of the ice rink must be controlled at -8.5 degrees Celsius, and the air 1.5 meters above the ice rink shall always be kept at 10 degrees Celsius. Besides, the spectator zone shall maintain a temperature between 16 to 18 degrees Celsius to offer a pleasant environment for the spectators.
It is learned that the temperature in the venue is controlled by a smart system consisting of over 4,000 sensors. This “smart brain” is able to monitor and control the temperature, humidity and PM2.5 concentration in the “Water Cube.” When temperature varies in different places of the venue, the system would make adjustment through the ventilation tubes.
Under the bleacher, there is a blue tube with a diameter of one meter circling the venue. It is a dehumidification and ventilation system. Ventilation devices can also be found under each seat.
The athlete and spectator zones have separate ventilation systems, and they can be controlled independently, said Yang Qiyong, head of the logistics department of the “Water Cube.”
According to him, the testing program was of high intensity and held in accordance with Winter Olympics standards, so that the athletes would feel that they were in real competition.