Numerical study of the flow of R1270‐based nanorefrigerants in a circular tube subject to uniform heat flux

Abstract

In this work, turbulent convective heat transfer of propylene (R1270)-based nanorefrigerant in a circular tube with a uniform heat flux of 20 kW/m 2 is numerically investigated using different types of nanoparticles namely Al 2 O 3 , CuO, SiO 2 and ZnO with a volume concentration ranging from 0 to 5%. Computations have been carried out using the commercial CFD code Fluent for Reynolds number ranging from 20,000 to 100,000 and a nanoparticle diameter of 30 nm. Results in terms of the average convective heat transfer coefficients of both pure R1270 and R1270-based nanorefrigerants have been compared successfully to values obtained using correlations from the literature. It is found that among nanorefrigerants studied, R1270/CuO performs the best, followed in order by R1270/Al 2 O 3 , R1270/ZnO and R1270/SiO 2. It is also shown that the convective heat transfer coefficient is enhanced by increasing the Reynolds number and the nanoparticles volume concentration.

Performance analysis of Al2O3–R718 nanorefrigerant turbulent flow through a flooded chiller tube: a numerical investigation

“…Figure 11 shows the comparison of pressure drop data for Al 2 O 3 -R718 nanorefrigerants at a particle volume fraction of 0.25% with pressure drop predictions made by using Eq. (25). The pressure drop data for Al 2 O 3 -R718 nanorefrigerant and the base fluid is summarised in Table 3.…”

“…Ahmed et al [22] conducted a numerical investigation for analysing the thermally radiative rotating flow of Maxwell nanofluid and concluded that the Brownian motion enhances the temperature field. Furthermore, few researchers have also conducted experimental and numerical studies on refrigerant based nanofluids (also known as nanorefrigerants) [23][24][25][26][27][28][29]. Helvaci and Khan [23] observed that the total entropy generation decreases with increase in Reynolds number in case of HFE 7000-based nanorefrigerants.…”

“…Helvaci and Khan [23] observed that the total entropy generation decreases with increase in Reynolds number in case of HFE 7000-based nanorefrigerants. Zohud et al [25] conducted numerical investigation on R1270-based nanorefrigerant and concluded that the heat transfer performance improves with increase in particle volume fraction.…”