Chemical - Engineering

          Three cases of heat transfer enhancement by turbulence promoters were adopted in order to increase the thermal performance of a double pipe heat exchanger of 1245 mm effective length, 28 mm outer diameter and changeable  inner diameter (11 or 14 mm). Wire coils of 1 mm diameter and 10, 20, 30 and 40 mm coiling pitches were used as turbulence promoters to augment heart transfer inside the inner tube of heat exchanger at a Reynolds number range of 5000 to 40000 based on smooth tube diameter.

Rheological study on carboxymethyl cellulose (CMC) dissolved in (6% NaOH in Water) solution was undertaken; Seven grades of carboxymethyl cellulose had been used.The Mw data were obtained by M-H equation using intrinsic viscosity data, where are obtained based on viscosity measurement.( 19,918, 45,700,76,693, 83,139, 148,800) gm/cm The values of Huggins coefficient (K3) have been obtained from plotting (ηredHvs conc.).

    The intrinsic viscosity and flow activation energy have been studied for several polymers which is used in some industrial applications, such as polyisobutylene of types Oppanol B150, 200,and 250 with different molecular weights of 2.5, 4.1 and 5.9 million g/mole, respectively, which dissolve in crude and gas oil.In addition three types of additives brought from Al-Dura refinery;olefin copolymer (OCP), {viscoples-4-677, viscoplex-215496, and Lubrizol R 7077} which dissolved in crude oil, and the polymers which is soluble in water such as polyacrylamide with