Direct numerical simulation of convective heat transfer in a pipe with transverse vibration

Effect of spatial development on convective heat transfer enhancement in a pipe with transverse vibration

“…The radial grid width is distributed so that the region near the pipe wall has the highest resolution. This resolution is verified in the aspect of radial distributions of the first and Mitsuishi, Takahashi, Shimura, Iwamoto and Murata, Journal of Thermal Science and Technology, Vol.16, No.1 (2021) second moments of turbulent statistics in the previous DNS with the periodic boundary condition in the axial direction (Mitsuishi et al, 2020).…”

“…In the main part, transverse vibration is modeled as the inertial acceleration of which the displacement amplitude is  and the frequency is f (Mitsuishi et al, 2020). In the present study, the displacement of the vibrating pipe observed from a stationary inertial frame is = − cos(2 ) in the vertical direction.…”

“…Parameters of the vibration are listed in Table 1 together with corresponding velocity amplitudes, = 2 , and some computational results for reference. Those values are chosen according to the previous parametric study by the authors (Mitsuishi et al, 2020). A distribution of increasing ratios of the average Nusselt number is cited from the previous DNS in Fig.…”

“…(2, f) = (1.6, 0.4), is discussed as a representative throughout this subsection. This set of vibration parameters follows the detailed analysis in the previous DNS study with the periodic boundary condition in the axial direction (Mitsuishi et al, 2020).…”

“…Recently, a novel technique was proposed to enhance the heat transfer by vibrating the pipe itself in the orthogonal direction to the pipe axis (Sakoh et al 2017;Mitsuishi et al, 2020). Direct numerical simulation of the convective heat transfer was performed with the periodic boundary condition in the axial direction.…”