<p> An experimental study of forced convection heat transfer and friction in water flowing in a vertical tube is reported in this thesis. The study investigates the effect of coiled wire turbulence promotors of various pitch to diameter ratios (ranging from 1.00 to 5.50) upon the Nusselt Prandtl modulus Nu/Pr^1/3 and Fanning friction factor f. The investigation is carried out for three different wire sizes, 0.052 in., 0.063 in., 0.072 in. respectively.</p> <p> Analysis of the various dimensionless numbers computed from the measurements of the present study indicates that the heat transfer increases by as much as 250% for low values of pitch to diameter ratio, though at the cost of a much larger increase in pressure drop.
Consequently, the tubes using coiled wire turbulence promotors can be employed with advantage for cases where pumping power is not the dominating factor and reduction in weight and size of the equipment are more important.</p> <p> The experimental data are empirically correlated in terms of the ratio of Nusselt numbers for the tubes with turbulence promoters to the empty tube as a function of Reynolds number and pitch to diameter ratio. Nu/Nuo = K(Re)^a (H/D)^-0.3 </p> <p> To evaluate the net effect of coiled wire turbulence promotors, the ratio j/f = [Nu/RePr^1/3]/f is plotted against Reynolds number. The curves for the coiled wire turbulence promotors fell below the theoretical curve for the empty tube indicating that coiled wire turbulence promotors are not advantageous in terms of heat transfer per unit pressure drop.</p> / Thesis / Master of Engineering (MEngr)
Identifer | oai:union.ndltd.org:mcmaster.ca/oai:macsphere.mcmaster.ca:11375/18562 |
Date | 11 1900 |
Creators | Kumar, Pramod |
Contributors | Judd, R. L., Mechanical Engineering |
Source Sets | McMaster University |
Language | en_US |
Detected Language | English |
Type | Thesis |
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