HEAT-EXCHANGER TUBE Russian patent published in 2002 - IPC

FIELD: heat-exchanging equipment. SUBSTANCE: heat-exchanger tube has smooth outer surface and structured inner surface. Inner surface is composed of parallel primary fins extending at an angle different from right angle with respect to tube longitudinal axis, and of secondary fins with respective inclined flat sides, channels defined at their sides by primary and secondary fins, and grooves formed on primary and secondary fins. Radial length of secondary fins is less than that of primary fins. Grooves are formed triangular. Groove mid longitudinal surfaces are arranged at an angle to tube longitudinal axis, which is different from right angle. Top surfaces of primary and secondary fins are formed rounded. Hollow spaces are formed between sides of primary and secondary fins and channels. Such construction provides for intensified flowing of fluid around channels. EFFECT: increased efficiency by uniform high evaporating or condensing capacity, simplified construction and reduced weight of fins. 22 cl, 6 dwg