Leveraging 3D Printing for the Design of High-Performance Venturi Microbubble Generators

Abstract

We present a miniaturized microbubble generator via three-dimensional (3D) printing for potential use in gas–liquid chemical reactions. We design it based on venturi channel structures to enable continuous gas dispersion by turbulent interactions and fabricate it using 3D printing for its high design flexibility and fast manufacturing speed. By experiments using water and nitrogen, we discuss quantitatively the dependence of the formed microbubble characteristics on operating conditions and geometric parameters. In particular, predictive models of Sauter mean diameter of daughter bubbles are proposed to help select proper operating and design parameters in order to achieve the desired level of microbubbles. To further improve the performance, we explore series- and parallel-venturi configurations and find that the parallel-based assembly performs significantly better. Therefore, we prove that the 3D printed venturi microbubble generator has high potential for the flow chemistry community to implement gas–liquid reactions.

Performance Evaluation and Scale-Up Behavior of an Engineered In-Line Mixer for 3D Printing

“…Specifically, several SAR micromixers in polydimethylsiloxane (PDMS) were reported with microfabrication methods; − however, many problems were encountered, including the lack of structural stiffness, poor organic solvent compatibility, difficulties in implementing challenging 3D structures, and small operating pressures. An avenue to overcoming those drawbacks is to use high-resolution 3D printing to make mixers with materials of sufficient chemical compatibility. , The SAR-type mixers provide a good demonstration of case study for their compact size and high design freedom, especially with a structure that would be impossible to machine from a single part using conventional subtractive manufacturing methods. For that purpose, we engineered an integrated SAR-type in-line micromixer based on the arrangement and array of a bundle of blades in a confined space, of which the smallest features were adapted to the manufacturing accuracy of a 3D printer, and the structural parameters (e.g., blade length and angle between blades) could be adjusted for specific applications.…”

Tailoring the Chain Entanglement by Nitrogen Bubble-Assisted Polymerization

“…A butter paper was applied to distribute the light uniformly. 23 A commercial software named Image-Pro Plus 6.0 was used to process the recorded images and calculate the size of bubbles. 22 The main steps were as follows: (i) selecting the reference length and determining the scale; (ii) setting the spatial calibration; (iii) selecting the processing region; (iv) setting the image gray threshold and identifying bubbles; and (v) obtaining the area S i of each bubble.…”

“…An LED floodlight was placed on the opposite side of the camera to obtain clear images of bubbles. A butter paper was applied to distribute the light uniformly . A commercial software named Image-Pro Plus 6.0 was used to process the recorded images and calculate the size of bubbles .…”

Microbubble Enhanced Bitumen Separation from Tailing Slurries with High Solid Contents

“…The previous literature demonstrates that the higher CO 2 holdup is adverse to generate tiny bubbles because large bubbles escape from shearing behavior at the divergent section. 49 As well, the significant CO 2 holdup accelerates the coalescence of bubbles.…”

“…Besides, a more vital turbulent interaction between slurry and gas in the divergent section decreases the bubble size effectively. 49 However, vapor bubbles accounted for a significant fraction of produced microbubbles. The collapse of vapor bubbles was strengthened in the more turbulent conditions.…”