Thermal‐Fluid Transport Phenomena of aStrongly‐Heated Gas Flow in Parallel Tube Rotation

Abstract

A numerical analysis is performed to study thermal transport phenomena in gas flow through a strongly heated tube whose axis is in parallel with the rotational axis. The velocity and temperature fields prevail when fluid flows in a rotating tube with uniform heat flux on the tube wall. The two-equationk-ωturbulence andt2¯-εtheat transfer models are employed to determine turbulent viscosity and eddy diffusivity for heat, respectively. The governing boundary-layer equations are discritized by means of a control volume finitedifference techniques. It is found that the Coriolis and centrifugal (or centripetal) forces cause fluid flow and heat transfer performance in the parallel-rotation system to be drastically different from those in the stationary case. Consequently, even if a tube rotating around a parallel axis is heated with high heat flux whose level causes a laminarizing flow in the stationary tube case, both the turbulent kinetic energy and the temperature variance remain over the pipe cross section, resulting in the suppression of an attenuation in heat transfer performance. In other words, an increase in tube rotation suppresses laminarization of gas flow.

Numerical Study of Convective Heat Transfer Enhancement in a Pipe Rotating Around a Parallel Axis

“…(10) agrees well also with experiments of Humphreys et al [5]. Numerical simulations of complex 3D fluid flow and heat transfer phenomena in the channels rotating around a parallel axis have been successfully performed by different authors for circular, square, rectangular and elliptic cross-sections using commercial and in-house software and different RANS turbulence models [2,3,5,13,14] (here RANS stands for Reynolds-Averaged NavierStokes). For instance, Mahadevappa et al [14] have numerically studied the heat transfer in pipes with rectangular and elliptical cross-section.…”

“…Maximal rotational velocity in all the other cited works was 50 s~' in Ref. [13], and the rest studied noticeably lower rotation rates. The experimental conditions, which we intend to study in our work, are close to those of Baudoin [10], which is the only reliable experimental dataset appropriate for the given geometry and validation of the CFD model against it.…”

“…Fluid fiow pattem and heat transfer intensity are affected also by the form of the channel cross-section. Several studies [4][5][6][7][8][9][10][11][12][13][14] have been done for pipes with circular, square, rectangular, and elliptic…”