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ISSN Online: 2377-424X

ISBN Print: 0-85295-345-3

International Heat Transfer Conference 10
August, 14-18, 1994, Brighton, UK

SIZE DISTRIBUTIONS OF ACTIVE NUCLEATION SITES WITH POOL BOILING HEAT TRANSFER AT SINGLE TUBES WITH DIFFERENT ROUGHNESSES

Get access (open in a dialog) DOI: 10.1615/IHTC10.4580
pages 63-68

Abstract

Size distributions of active nucleation sites with pool boiling heat transfer at single tubes with different roughnesses have been calculated from measurements with propane, n−hexane and R114 within wide ranges of heat flux (50 to 105 W/m2) and pressure (1 to 90 per cent of the critical pressure). Model assumptions on the heat transfer connected with growing and detaching bubbles have been modified, and it is shown that great differences in the calculated data result from the great scatter within the experimental data of bubble departure diameter and frequency, existing in the literature. In addition, size distributions of form parameters are established from measured surface roughness profiles of the test tubes and compared with the size distributions of bubble radii within the active nucleation sites.