Heat exchanger

Abstract

Each fin 30 is designed to have continuous lines of wave crests 34 and continuous lines of wave troughs 36 arranged at a preset angle in a specific angle range of 10 degrees to 60 degrees relative to the main stream of the air flow and symmetrically folded back about folding lines of a preset folding interval W along the main stream of the air flow. A ratio (a/p) of an amplitude ‘a’ of a waveform including one wave crest 34 and one adjacent wave trough 36 to a fin pitch ‘p’ satisfies a relation of 1.3×Re−0.5<a/p<0.2. A ratio (W/z) of the folding interval W to a wavelength ‘z’ of the waveform satisfies a relation of 0.25<W/z<2.0. A ratio (r/z) of a radius of curvature ‘r’ at a top of the wave crest 34 or at a bottom of the wave trough 36 to the wavelength ‘z’ of the waveform satisfies a relation of 0.25<r/z. The continuous lines of the wave crests 34 and the continuous lines of the wave troughs 36 are arranged to have an angle of inclination a of not less than 25 degrees at a cross section of the waveform. This arrangement effectively improves the heat transfer coefficient of a heat exchanger and thereby allows effective size reduction of the heat exchanger.

Dependencies are inferred from the claim text.