Augmentation of forced-convection heat transfer in roped tubes and investigation of variation of the heat transfer coefficient and friction factor for both laminar and turbulent flow

Abstract

Since the geometry of roped tubes and smooth tubes are different, the flow characteristics and the heat transfer coefficients associated with each tube are also different. Because of improved geometry it is possible to attain higher heat transfer coefficients in the case of roped tubes. However, the increase in the heat transfer coefficient is unavoidably associated with higher pressure drops. Therefore, the use of roped tubes with the intention of achieving high heat transfer rates is necessarily subject to justification. The intention of the present work is to determine, experimentally, the flow and the heat transfer characteristics of roped tubes selected from a representatiife.class, to compare these characteristics with that of smooth and other profiled tubes, and thus to provide a quantitative basis for the justification of the use of such tubes to achieve high heat transfer rates with small size equipment.