الفهرس 
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Abstract
The prosent investigation deals with the study of heat transf~r in drag reducing fluid systems at rotating cylinders. Since there is aclos~ analogy between huat and mass transfer and because of th0 technical difficulties involved in m0asur1ng hoat transfur :irl dlUig ruducing fluids, the present work was carri0d out by measuring rates of mass transfer. Rates of mass transfur between arotating cylinder and drag reducing fluids woro measured by the olectrochemical technique ov~r arango of Reynolds number from 750 to 10,000 and polymer concentration from 10 to 500 p.p.m.
Two polymers wore triad as drag reducers, Polyothylone oxide (Polyox) and Carboxymethyl c~lluloso. The ~loctrochom1~•oal tcchniquo involv~d measuring the limiting current for Cathodic reduction of potassium ferricyanidc in alarge excoss of sodium hydroxido. The study was Qxt~ndod to rough rotating cylinders, roughness was made by ongraving parallel linos along the test oylinder, five dGgroes of roughnoss wore used with relativo roughnoss (old) ranging from 0.0185 to 0.075. <The study revealod the following results: Mass tran§f~r rat~s were found to docroase by amaximum of 43% in prosonco of drag reducing agonts (Polymers).
extent of this docreaso was found to depend on polymer entration. Roynolds number, s~iace roughness and type The % reduction in thG ratv of mass transf~r was found with Polymer conc~ntration and Roynolds number. ox wae found to roduco the rata of mass transfer than reduction in the rate of mass transfer was found decreaso with increasing the degreo of surface ronghness. s transfwr data undor diffcr~nt conditions wore correlated ing tho mGthod of dimensional analysis. the following replonts the diffcront correlations obtainod :
For mass transfor bctwGun rough ~otating cylinder and Polym~r free solutions, tho data fit the equation. /1)°•2 ur• , I For mass transfer botw~Gn smooth rotating cylinder and solutions containing polyox, the data fit th~ equation.
For mass transfer between rough rotating cylinder and solutions containing polyox, the data fit the equation.
8t = 0.7647 Re-O•36 8c-O•669 (e;(d)0.36