Research Note — RES‑008 · Computational Fluid Dynamics

CFD of a 19‑Tube Bundle Flow Straightener

Computational Fluid Dynamics · Iran University of Science and Technology · ANSYS Fluent

A CFD study of a 19‑tube bundle flow straightener installed just downstream of a pipe elbow. Flow exiting an elbow carries strong swirl and asymmetric velocity profiles — a tube‑bundle straightener breaks that swirl into 19 parallel channels, forcing the flow to re‑develop as a more uniform, axi‑symmetric profile before it reaches downstream equipment or a flow meter.

Part 1

Geometry & Setup

• Modeled a 90° pipe elbow feeding into a 19‑tube bundle straightener in SolidWorks
• Meshed and solved the domain in ANSYS Fluent as a turbulent, steady, incompressible flow with the k‑ε turbulence model
• Resolved both the swirling elbow flow and its redevelopment through the 19 parallel straightener tubes

SolidWorks model — 19-tube bundle

Part 2

Flow Redevelopment Through the Bundle

• Visualized streamlines through the elbow and straightener, showing how the bundle divides the swirling flow into 19 parallel streams
• Tracked the velocity contour along the elbow and straightener centerplane — velocity peaks inside the tubes as swirl is broken up and the profile flattens
• Evaluated the outlet velocity contour, showing each of the 19 channels developing its own more‑uniform profile by the bundle exit

Streamlines — elbow & tube bundle Centerplane velocity contour Outlet velocity contour — 19 tubes