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ISSN Online: 2377-424X

ISBN Print: 0-89116-559-2

International Heat Transfer Conference 8
August, 17-22, 1986, San Francisco, USA

MEASUREMENTS OF LOCAL MASS TRANSFER COEFFICIENTS AND PRESSURE DISTRIBUTION ALONG THE SHELL-SIDE OF OVAL-SHAPED TUBES IN CROSS FLOW HEAT EXCHANGERS

Get access (open in a dialog) DOI: 10.1615/IHTC8.1160
pages 2721-2726

Abstract

Measurements of local heat transfer coefficients and pressure distribution on the shell-side of oval shaped tubes were carried out for two staggered cross-flow tube banks having different relative longitudinal pitches. The naphthalene-sublimation technique in conjunction with the analogy between heat and mass transfer has been used to investigate the heat transfer. Local heat transfer coefficients obtained by this method are compared with calculated ones. These calculations were carried out with the aid of an integral boundary layer method which takes account of the measured pressure distribution along the tube surface. For tube banks with relative longitudinal pitches of t1 = 1.0 the excellent agreement between the calculated and the measured local heat transfer coefficients show that the local heat transfer can be obtained just from the measured distribution along the surface. For tube-banks with t1 = 0.67 the laminar boundary layer separates already on the upstream side of the tubes. In consequence of this the level of the local Nusselt-number distribution is considerably higher compared to banks with t1 = 1.0