Investigation of three dimensional flow in pipe fittings

In this study, three dimensional turbulent flow in 90° elbows with different diameters have been numerically investigated for different stream velocities using air, natural gas and water. Mesh structure convenient with geometry has been constructed with ICEM CFD and the predictions of flow field have been performed with commercial software Fluent. Simulations have been carried out by using Standard k-, RNG k- and SST k-ω turbulence models and best turbulent model for flow through elbow has been investigated. For flow conditions studied, pressure and velocity distributions have been obtained and local loss coefficients have been calculated. It has been found that SST k-ω turbulence model is more consistent with the experimental results when compared to others. The local loss coefficients for elbow flow have not constant value and decreases with increasing pipe diameter and stream velocity.