## THERMAL SCIENCE

International Scientific Journal

### Thermal Science - Online First

online first only
### Heat transfer in a triangular wavy channel with CuO/water nanofluids under pulsating flow

**ABSTRACT**

In this paper, heat transfer and pressure drop characteristics of CuO-water nanofluid flow in a isothermally heated triangular-wavy channel under pulsating inlet conditions are numerically investigated. A numerical simulation is conducted by solving the governing continuity, momentum and energy equations for laminar flow using the Finite Volume approach(FVM). In the studies, the main parameters including the Reynolds number, pulsating amplitude and frequency, are changed while the nanoparticle volume fraction and the other parameters are kept constant for all cases. Numerical results are compared with the steady flow conditions, which showed that heat transfer performance significantly increases due to improve thermal conductivity and the use of nanoparticles in the pulsating flow conditions. The results indicate that there is a high potential for promoting the thermal performance enhancement by using nanoparticles under pulsating flow in wavy channels. It is found that the heat transfer enhancement increases with increasing pulsating amplitude and Reynolds number, and there is a slight increase in pressure drop. The obtained results are given as a function of dimensionless parameters.

**KEYWORDS**

PAPER SUBMITTED: 2016-10-18

PAPER REVISED: 2016-10-23

PAPER ACCEPTED: 2017-01-25

PUBLISHED ONLINE: 2017-02-12

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