(552c) Visualization of Newtonian Pipe Flow Around Static Mixers: 3-D Printing Applications in the ChE Curriculum

A laboratory demonstration to study Newtonian pipe flow around a static mixer was designed and constructed. The equipment constructed is simple, cost-effective and can be used to study and visualize pipe flow and the effect of static mixers. The experimental system consists of ½ in. diameter clear Tygon^® tubing, a flow meter and pressure gauges. Water and a water-based dye were used as fluids for all experiments. The demonstration module is portable, self-contained and can be connected to laboratory water. A standard helical static mixer was designed using SolidWorks^® and constructed from PLA using a 3-D printer. The designed experiment can be used to introduce students to chemical engineering applications of 3-D printing and prototyping. A 1/16 in. diameter stainless steel tube was used to introduce blue dye into the center of the flow tube. This allowed for the visualization of fluid mixing in the system. Successful validation of the equipment included experiments with and without the static mixer. All visual observations were recorded and image analysis software was used to provide a semi-quantitative measure of mixing quality. The equipment allows for pressure drop measurements to investigate the effect of the static mixer on pressure drop and on the Reynolds Number v. friction factor relationship for pipe flow. The module described here can be used in fluid mechanics courses for standard pipe flow studies, visualization of flow characteristics, and for mixing studies with low viscosity Newtonian fluids. The experiments can be highly visual and excellent for use in K-12 outreach efforts.