FREE CONVECTIVE MASS TRANSFER BEHAVIOR OF FINNED TUBES

Rates of natural convective mass transfer at vertical and horizontal finned cylinders were determined by an electrochemical technique that involved measuring the limiting current of the cathodic deposition of copper from acidified copper sulfate solution. Variables studied were fin spacing (s), fin diameter (d), and physical properties of the solution. For vertical and horizontal finned tubes it was found that the mass transfer coefficient increases with increasing fin height and decreases with increasing fin separation. Rates of mass transfer at vertical and horizontal finned tubes were found to be higher than that at unfinned (plain) tubes by an amount ranging from 44% to 96%. Although the degree of mass transfer enhancement by fins is higher at vertical cylinders, horizontal finned cylinders have higher mass transfer coefficients than vertical finned cylinder under the same conditions. Mass transfer data at vertical finned cylinders were correlated by the equation while mass transfer data at horizontal...