Use of smaller-diameter copper tubes in evaporator and condenser coils is leading to more efficient Chinese refrigeration products.
This year's recently concluded China Refrigeration Exposition showed a trend toward using smaller copper cooling fins and tubing as a means of realizing better heat transfer efficiency. Manufacturers adopting this approach included Chigo with an indoor evaporator unit of a split system; Haier with a window air-conditioning system; and Kelon wiht a split-system, including an outdoor condenser as well as the indoor evaporator.
The International Copper Association says these products represent the first generation of a technology called MicroGroove, basically copper heat transfer components with unusually small dimensions. For example, new fin designs tailored to smaller tubes could bring about further improvements in performance. And new refrigerants benefit from the smaller tube volumes, ICA says.
“We are at the threshold of a new era in product design based on smaller diameter inner-grooved copper tubes,” says Nigel Cotton, MicroGroove Team Leader for the International Copper Association. “Major advantages accrue from the smaller diameters and inner grooves of the copper tubes,” Cotton says. “The improvements are driven by engineering fundamentals. Heat transfer is improved for smaller tubes with enhanced surfaces.”
Interestingly, use of copper tubes and fins with smaller dimensions often lets manufacturers use less material. “It sounds impossible but the heat transfer capacity per unit of copper actually increases as the tube diameter shrinks,” he explains. “That’s why so many manufacturers are adopting this new technology.” ICA says the consumer benefits because the final product weighs less and takes up less space yet the performance is the same or better than larger products.
