Turbulence in a microscale planar confined impinging-jets reactor

Area of Science:

• Chemical Engineering
• Fluid Dynamics
• Microreactor Technology

Background:

• Confined impinging-jets reactors (CIJR) are advantageous for microscale chemical processing, including nanoparticle synthesis.
• Computational fluid dynamics (CFD) shows potential for designing and scaling up CIJRs.
• Lack of experimental data for microscale turbulence hinders CFD model validation.

Purpose of the Study:

• To address the limited experimental data for validating CFD models in microscale turbulent flows.
• To measure and quantify unsteady flow fields in a planar CIJR.
• To validate a specific CFD model (two-layer k-epsilon) using experimental data.

Main Methods:

• Utilized microscopic particle-image velocimetry (microPIV) to capture instantaneous velocity fields.
• Conducted experiments in a planar confined impinging-jets reactor across various Reynolds numbers.
• Compared experimental velocity data with predictions from a two-layer k-epsilon CFD model.

Main Results:

• Successfully measured instantaneous velocity fields in a planar CIJR.
• Provided quantitative data on microscale turbulent flow characteristics.
• Evaluated the performance of the two-layer k-epsilon CFD model against experimental measurements.

Conclusions:

• This study represents the first direct measurement and quantification of velocity and turbulence in a microreactor for CFD model validation.
• The findings facilitate the validation of CFD models for microscale turbulent flows.
• Enables more accurate "experiment-free" design and scale-up of CIJRs for applications like nanoparticle production.