Predict performance characteristics of Blowers using CFD

Background

A Blower manufacturer based in North America received some tough feedback from its customers.

Customers wanted the company to design blowers with significant reduction in energy consumption (at least 10% to 15%) as well as the lowering of operating noise levels. And this had to be achieved without compromising the quality of its output.

Without these improvements in their next product variant the company significantly risked losing market share. They decided to follow a CFD-led product design process to achieve these aggressive design goals.

Technical approach

To achieve the goals we did a computational study of the following design parameters:

  • Blade Angles
  • Angular Velocity
  • Flow Rate
  • Number of Blades

Results of CFD Analysis

Based on the CFD simulations:

  • We were able to predict blower noise using Computational Aero-Acoustics models.
  • We were able to predict noise generation due to turbulence and an unsteady rotor–stator interaction.
 

We then validated these results against experimental data.

Recommendations made for improved design

The mandate of the project was to predict performance to enable design improvements using CFD which we accomplished.
With performance prediction we recommended the following design improvements:

  1. Changing number of rotor-stator blades
  2. Modification of the shape of the blade
  3. Modification of the Assembly
  4. Design changes to reduce noise levels

Conclusions

  • The CFD-led design process helped achieve the design goals of improved efficiency levels between (10-15%) plus a reduction in operating noise level. Acoustic Models helped in the effective prediction of noise levels of the blower under various operating conditions.
  • Additionally, the use of CFD simulations reduced design costs by reducing the number of prototypes needed for physical testing.