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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

AN ANALYSIS OF THE UNIFORM NAPHTHALENE LAYER MASS TRANSFER ANALOGUE METHOD APPLIED TO LAMINAR FLOW OVER A FLAT PLATE

Get access (open in a dialog) DOI: 10.1615/IHTC8.2570
pages 495-499

Abstract

The measurement of the time for removal of a uniform layer of naphthalene of known thickness has been extensively used as a method of determining local mass transfer coefficient distributions and hence, by analogue, heat transfer coefficients also. However it suffers from the drawback that once the layer has been completely removed at any location, then the mass transfer analogue for uniform surface temperature i.e. uniform surface concentration has been lost. This paper describes work that has been done to determine the significance of this loss of analogue for the simple case of laminar flow over a flat plate. The equations desribing the boundary layers as functions of location and time have been set up and solved. The results suggest that values of heat transfer coefficient calculated by ignoring this effect will be in error by a constant 37% at all locations for this configuration. Experimental tests have confirmed that the usual assumption that the loss of analogue is unimportant, can lead to significant errors.