Numerical and Experimental Investigation of Heat Transfer Features in a Square Duct with Internal Ribs

Abstract

In this work, experimental investigation and numerical prediction were completed to study the heat transfer for disturbed flow in square passage heated from upper and lower aspect through the use of technology to heighten the heat transfer action by the use of different ribs shapes (semicircle, triangular and square) with the same surface area and height, distributed on the superior and inferior aspect of the heated channel. The experimental part included designing and manufacturing test apparatus and run the tests through operational parameters (Reynolds number 10460-40500) and heat flux (138-6888) W/m^2. While the design parameters included different ribs shapes (circular, triangular and square). Numerical investigation was done by using ANSYS FLUENT14.0 program, depending on Navier–Stokes equations, application of turbulence model k-ε and energy equation for the air were implemented for the same experimental conditions for all ribs type. In conclusion, the additions of ribs make noticeable enhance of the heat transfer compared to without ribs. Square ribs provide the best enhancement in heat transfer by (28.22-58.23) % compared to without ribs. Then comes the triangular and circular ribs that provide enhancement by (20.14-45.62) (10.87-28.13) % respectively. In addition to that, arrange the ribs in staggered pattern on the upper and lower aspect give the best heat transfer.

Keywords

• ribs
• numerical simulation