FORM -2 THE PATENTS ACT, 1970 (39 of 1970) & THE PATENTS RULES, 2006 PROVISIONAL SPECIFICATION (See section 10 and rule 13) ENHANCEMENT OF HEAT TRANSFER COEFFICIENT IN PIPES USING DIMPLED TUBE CONFIGURATION THERMAX LTD an Indian Company of D-13, MIDC, Chinchwad Pune-19, India. THE FOLLOWING SPECIFICATION DESCRIBES THE INVENTION. FIELD OF THE INVENTION The present invention relates to the field of heat exchangers. Particularly, the present invention relates to the enhancement of heat transfer coefficient in heat exchangers. DEFINITIONS OF TERMS USED IN THE SPECIFICATION The term "Nusselt number (Nu)" used in the specification is the ratio of convective to conductive heat transfer across (normal to) the boundary. The term "Reynolds number" used in the specification is a dimensionless number that gives a measure of the ratio of inertial forces to viscous forces. The term "frictional loss/factor (f)" refers to the loss in flow momentum due to drag offered by the wall roughness while moving through a pipe, hose, or other limited space. The term "Reynolds-Averaged Navier-Stokes equations" used in the specification are time (ensemble)-averaged equations of motion for fluid flow. The term "dimples" used in the specification are projections or depressions on the surface of the tube. Enhancement efficiency: It is defined as: where is heat transfer enhancement efficiency and subscript "0" refers to the corresponding values for the smooth tube. Other Correlations Used: To get friction factor and Nusselt number for smooth tubes, Petukhov's correlations have been used: Friction factor: f = (0.7901n Re - 1.64)"2 for3000=