to investigate the effects of inserting coiled wires in tubes on the fluid dynamic and heat transfer performance ofv nanofluids. The numerical simulations of nanofluids are performed using two phase mixture model. The flow regime and the wall boundary conditions are assumed to be laminar and constant heat flux respectively. The effects of inserting coiled wires in tubes on different parameters such as heat transfer coefficient, pressure drop, temperature distribution, velocity distribution and secondary flows are presented and discussed. The results show that using coiled wire in tubes leading to increase in about 13.44% but increase the p about 14.66% with respect to the flow without nanofluid and coiled wire. Similarly, using nanofluid leading to increase in about 5.52% but increase the p about 8.92%. Finally, using both of the mentioned heat transfer enhancement mechanisms leading to increase in about 17.51% but increase the value of p about 22.86%.
