Effect of torsion on convective heat transfer in a helicoidal pipe heat exchanger
Conference
Yang, G, Dong, ZF, Ebadian, MA. (1992). Effect of torsion on convective heat transfer in a helicoidal pipe heat exchanger
. American Society of Mechanical Engineers, Heat Transfer Division, (Publication) HTD, 212 71-79.
Yang, G, Dong, ZF, Ebadian, MA. (1992). Effect of torsion on convective heat transfer in a helicoidal pipe heat exchanger
. American Society of Mechanical Engineers, Heat Transfer Division, (Publication) HTD, 212 71-79.
This paper presents a numerical investigation of fully developed laminar convective heat transfer in a helicoidal pipe (non-zero pitch coil pipe). The helicoidal pipe is subjected to the thermal boundary condition of axial uniform wall heat flux and peripheral uniform wall temperature. In this study, three major parameters are identified to control heat transfer in a helicoidal pipe: the Dean number, torsion, and the Prandtl number. The results indicate that torsion will increase the temperature gradient on one side of the pipe wall and decrease the temperature gradient on the other side of the pipe wall, that is, torsion makes the temperature contour asymmetry. The deformation of the temperature distribution is enhanced dramatically when the Prandtl number increases. This investigation also reveals that torsion may significantly reduce the Nusselt number in a helicoidal pipe. In the case of a small Prandtl number, the peripheral Nusselt number declines slightly as torsion increases. However, in the case of a large Prandtl number fluid, the Nusselt number is significantly reduced as torsion increases. Furthermore, the predicted results for the limiting cases are compared with other numerical and experimental results available in the open literature. An excellent comparison is obtained in all cases.
