Chilled beam lindab | we simplify construction Carat Radiation exchange in chilled beams creates no air movement Function As cold water passes through the chilled beam, the warm air from the room is cooled on the cold surface of the beam. The cooled air (which has a higher density) then streams through the chilled beam and down into the room (see Picture 2). This leads to air circulation in the room, where warm air from the room is continually replaced by cooled air. The cold surfaces of the beam also absorb heat radiation from warmer surrounding surfaces. The high radiation quotient leads to direct heat exchange between the cold surfaces of the beam and the warm surfaces in the room. The radiation quotient for Carat is approx. 35% of the total emitted cooling effect. This is a high quotient, compared to conventional finned battery beams, which have a radiation quotient of approx. 5%. Direct heat exchange, through a high quotient of radia- tion to the room surfaces, and a high cooling effect, even at lower room temperatures, allows a large amount of cold to be stored efficiently in the building structure dur- ing low-load periods. The overall result is that Carat gives off more cooling energy during a 24-hour period than a finned battery beam. This means that a lower room tem- perature can be achieved. Picture 1. Cross-section of Lindab's unique strips. The rhomboid shape provides an efficient heat- transfer surface. Optimal design Construction Carat is a chilled beam that absorbs heat by both radia- tion and convection. By optimising the beam's radiation quotient, output has been increased by 50% compared to finned battery beams, without increasing the risk for drafts. Carat is based on a method that is unique in the world: in a cold-rolling process, the copper pipe is connected by metallurgical bonding to a gilled aluminium sheet. The energy transfer between the cooling surface and the water circuit is made more efficient, which results in a high cooling effect per surface unit. The technology for the metallurgical bonding of copper and aluminium ren- ders galvanic corrosion impossible. Carat is available in widths from 31 cm to 84 cm. The length can vary from 1.2 m to 6.0 m. Carat provides a high cooling effect per surface unit, which leads to resource-efficiency and a low weight for the product. Carat is made of 100% recyclable materials. The water pipes are made of copper. Nevertheless, the water should be oxygen-free to prevent corrosion. Easy to clean Hygiene Carat's surface area is four times smaller than that of a corresponding finned battery beam with the same perfor- mance. All parts of the product are accessible for clean- ing and inspection. These qualities, together with the rel- atively strong aluminium plate, make Carat easy to wipe and clean. Picture 2. How Carat works. Lindab reserves the right to make changes without prior notice 3 2019-02-28
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