Numerical Investigation of 180o Curved Diffuser Performance by Varying Geometrical and Operating Parameters

Shamsuri  Rasidi; Suzairin  Md Seri; Normayati  Nordin; Muhammad Zahid  Shariff; Nurul Fitriah  Nasir; Sharifah  Adzila; Raudhah  Othman

Authors

Shamsuri Rasidi Faculty of Mechanical and Manufacturing Engineering, Universiti Tun Hussein Onn Malaysia, Parit Raja, 86400 Batu Pahat, Johor, Malaysia
Suzairin Md Seri Faculty of Mechanical and Manufacturing Engineering, Universiti Tun Hussein Onn Malaysia, Parit Raja, 86400 Batu Pahat, Johor, Malaysia
Normayati Nordin Faculty of Mechanical and Manufacturing Engineering, Universiti Tun Hussein Onn Malaysia, Parit Raja, 86400 Batu Pahat, Johor, Malaysia
Muhammad Zahid Shariff Faculty of Mechanical and Manufacturing Engineering, Universiti Tun Hussein Onn Malaysia, Parit Raja, 86400 Batu Pahat, Johor, Malaysia
Nurul Fitriah Nasir Faculty of Mechanical and Manufacturing Engineering, Universiti Tun Hussein Onn Malaysia, Parit Raja, 86400 Batu Pahat, Johor, Malaysia
Sharifah Adzila Faculty of Mechanical and Manufacturing Engineering, Universiti Tun Hussein Onn Malaysia, Parit Raja, 86400 Batu Pahat, Johor, Malaysia
Raudhah Othman Faculty of Mechanical and Manufacturing Engineering, Universiti Tun Hussein Onn Malaysia, Parit Raja, 86400 Batu Pahat, Johor, Malaysia

Keywords:

pressure recovery, flow uniformity, CFD, curved diffuser

Abstract

The geometry of a curved diffuser often inviting the flow to separate. The flow separation phenomenon plays a vital role in the recovery of pressure inside the diffuser. Besides, the geometrical and operating aspects of a curved diffuser have always been taken into consideration in most relatable researches. Pressure recovery and flow uniformity of a steady, developed entering turbulent flow of a circular-sectioned 180° curved diffuser has been investigated numerically by varying geometrical and operating parameters. The curved diffuser with area ratio (2, 3 and 4), radius of inlet and curvature of respectively 50 mm and 180 mm was considered. Different values of Reynolds number 6 × 104 ,12 × 104 ,18 × 104 ,24 × 104, and 30 × 104 were tested in every area ratio set. ANSYS code Fluent was used to run the simulation by considering different turbulence models, i.e. the standard k-???? turbulence model (std k- ????), Spalart-Allmaras turbulence model (SA), k-kl-???? transition turbulence model and transition SST model. The present work proposed the curved diffuser with AR=2 operated at Re=6x104 as the optimum set of parameters, with minimal flow separation occurring in the system.