Pressure loss in a 180-degree sharp bend: Results of URANS and LES computations compared with experimental data

Аuthors

Panov D. O.^*, Yukhnev A. D.^**

Peter the Great Saint-Petersburg Polytechnic University, 29, Polytechnicheskaya str., St. Petersburg, 195251, Russia

*e-mail: : dopanov@gmail.com
**e-mail: a.yukhnev@mail.ru

Abstract

Numerical simulation of turbulent flow in a square sectioned 180-degree strong bend has been performed at Re = 2.1·10⁴, 4·10⁴ and 6·10⁴ employing URANS and LES approaches. Experimental data for Re-sensitive pressure losses has been obtained for the Reynolds number ranging from 3.5·10³ to 6·10⁴. This data is in a good agreement with the well-known measurement results obtained for a higher Re range, Re > 5·10⁴, where the pressure loss coefficient is practically Re‑independent. Mean flow patterns and pressure losses predicted with the two simulation approaches are compared. The URANS based computations, performed with the k‑ω SST turbulence model, give considerably underrated values of the pressure loss coefficient, by about 20%. Results of computations performed with the LES‑WALE model practically coincide with the measurement data.

Keywords:

U-duct, turbulent flow, numerical simulation, LES

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