Numerical evaluation of the heat transfer in a shell and corrugated coil tube heat exchanger with three various water-based nanofluids

摘要

In this paper, turbulence heat transfer and nanofluid flow in a shell and corrugated coil tube heat exchanger are evaluated numerically. The three-dimensional numerical simulations have been done by finite volume method using a commercial computational fluid dynamics code. The spatial discretization of mass, momentum, turbulence dissipation rate, and turbulence kinetic energy equations has been achieved by a second-order upwind scheme. A SIMPLE algorithm has been used for velocity-pressure coupling. To calculate gradients, Green-Gauss cell-based method has been utilized. The cross-section of the coil tube is lobe shaped. First, the impact of corrugated tube cross-section type and then, the impact of utilizing different types of nanofluid on thermal performance are investigated. The outcomes indicate that at high Reynolds number, utilizing a five-lobe cross-section causes augmentation in Nusselt number and pressure drop by about 4.8% and 3.7%, respectively. However, the three-lobe type shows the highest thermal performance. Moreover, water/CuO has the most thermal performance. As the volume concentration of the nanofluid increases, the thermal performance declines.