Heat transfer characteristics of double pipe heat exchanger having externally enhanced inner pipe

An investigation on enhancement of heat transfer is carried out for a double pipe exchanger in which the outer wall inner provided with circumferential labyrinth passages. Rectangular and triangular cavities fixed tooth thickness, height, pitch are considered effect added structures characteristics discussed. A two-dimensional steady numerical simulation using ANSYS-FLUENT software. The flow Reynolds number equals to 20 000 43 hot cold fluids, respectively, while other fluid properties constant. From analysis this work, it identified that passages exchange surface improve rate can reduce length exchanger. Numerical predictions agree well results obtained from experiment conducted.