Abstrait

Numerical Investigation of Heat Transfer Characteristics in A Square Duct with Internal RIBS

Abhilash Kumar, R. SaravanaSathiyaPrabhahar

Attaching rib turbulators to a flow passage is an effective means of enhancing heat transfer. Rib turbulators are effectively used in serpentine cooling air channels for the internal cooling of turbine blades. Periodic ribs are frequently employed to enhance the heat transfer process in various cooling passages. The reason that ribs increase the fluid flow turbulence near the wall and disrupt the laminar boundary layer to enhance the heat transfer. The other reason is that the ribs also increase the heat transfer area. However, the thermal/hydraulic performance of the ribs is affected by many factors including the holes in a rib, size and spacing. The present investigation involves the numerical analysis of heat transfer characteristics of a square channel roughened with plain, rectangular perforated ribs of rounded corners and elliptical perforated ribs in the flow direction on two opposite walls. The model is created using GAMBIT 2.4.6 software. Numerical simulations were performed using the CFD software package ANSYS 14.5 FLUENT. Turbulence closure was achieved using the shear-stress transport (SST) k-ω model. From this, the heat transfer characteristics of plain, rectangular perforated ribs of rounded corners and elliptical perforated ribs were plotted.