A numerical study is performed to investigate thermal transport phoenomena in a process of laminarization from a turbulent flow in a strongly heated circular tube in coaxial rotation. The k- epsilon turbulence and t~2- epsilon _t heat-transfer models are employed to determine the turublent viscosity and eddy diffusivity for hear,m respectively. The governing boundary-layer equations are discretized bymeans of a control volume finite-difference technique and numerically solved using a marching procedure. When the tube is at rest, it is disclosed that: (i) when laminarization occurs, the streamwise velocity gradient at the wall is diminished along the flow, resulting in a substantial reduction in the turbulent kinetic nenergy over the whole tube cross section, (ii) the attenuation cases a deterioration in heat transfer perormance, and (iii) simulaneously, both the turbulent heat flux and temperature variance diminish over the whole tube cross section in the flow direction. However, the presence of tube rotation contributes to the promotion of laminarization of gas flow. The mechanmism is that a reduction in the velocity gradient induced bytube rotation suppresses the production of turbulent kinetic energy, resulting in an amplification in laminarizing the flow process.
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