INTRODUCTION

Multistage centrifugal Blower consist of stators & rotors. CFD is widely used to determine the performance curves of Blower and to identify the flow separation issues within rotor & stators. CFD provides proper insight about the performance of Blower by closely simulating the air flow within various passages of Blower. Proper mesh resolution within the impeller region and appropriate selection of interface model between stator & rotor interface is very important for predicting the accurate performance of blower.

CHALLENGES

• Appropriate splitting of rotating and non-rotating regions of Blower.
• Meshing of rotor and stator for very low Y+ requirement.

THE SOLUTION

It is very important to extract proper periodic passage of rotor for generating good quality structured hex mesh within complete rotor. Complete Mesh was manually controlled to keep the mesh count within limits and at the same time capture the critical regions. Head generated across rotors and head loss across stators of Blower was extracted for various flow rates conditions. Blower performance curves i.e. Head, Power, Efficiency Vs flow rate curves were generated and compared with available test data. Flow recirculation regions were identified for all flow rate conditions and accordingly design modifications were suggested in rotor blade profile and stator design for keeping flow recirculation & losses minimum.

BENEFITS

• Virtual testing of the Blower for various flow rate conditions.
• Prediction of flow recirculation regions within rotor/ stator passages.
• Prediction of pressure distribution in rotor/stator.