The present paper study experimentally shell and coiled tube heat exchanger performance with two different configuration of copper coiled tubes at two different angles, 0° and 45°.Five heat exchangers of counter flow arrangement were fabricated with at different values of coil torsions (λm) and the same mean diameter of the coil (Dc), coiled tube diameter (dt) and curvature ratio (δ). Experiments carried out at different flow rates of the tube side (60-268 lit/hr) and keeping the shell side flow rate at 60 lit/hr. The effects of mean coil torsion, tube side flow rate and the cone angle were investigated. Results showed that Nu of the tube side and coefficient of heat transfer increases by decreasing the mean coil torsion. At small and high values of Reynolds number (Ret), the average increase in convection heat transfer coefficient (ht), tube side Nusselt number (Nut) and the overall heat transfer coefficient (Uov) is of 124% to 122%, 126% to 122% and 54% to 32% respectively, when the coil torsion decreases from 0.052 to 0.0202. Also, results illustrated that Nut decrease with the increase of cone angle from 0° to 45 °. For the two different angles (0° and 45°), the augmentation in Nut at λm=0.0202 and λm=0.052 is of 52 % to 49% and 81% to 77% respectively. Moreover, correlations for Nut at the two different cone angles are obtained. |
