(293g) Rapid Prototyping: Impeller Design Using 3-D Printing and  Data Analysis to Enhance Creativity and Critical Thinking in the Chemical Engineering Curriculum

Integration of educational modules in core chemical engineering courses is an effective way to familiarize students with new technologies within the standard four-year undergraduate curriculum. This work involves the development of educational modules and laboratory experiments to introduce 3-D printing rapid prototyping and advanced data analysis to students. The modules and experiments are self-contained and flexible allowing for their use in a wide range of courses at every level of the curriculum. Rapid prototyping is becoming essential for efficient and cost-effective equipment and process development in many industries. For many applications, ranging from biomedical devices to industrial scale impeller design, 3-D printing is an important element in the rapid prototyping tool box of the chemical industry. The educational modules presented here familiarize students with the rapid prototyping design process. Students design and 3-D print impellers and use experimental design techniques to test these in laboratory scale tank-type mixing equipment. Solid/liquid system cloud height and off-bottom velocity are used to characterize the process, and to develop models for mixing efficiency as a function of process parameters (liquid height and impeller distance from tank bottom), fluid viscosity and particle properties. The mixing characteristics of polylactic acid (PLA) 3-D printed axial and radial impellers were studied as well as mixing characteristics of more complex designs such as jet and lily impellers. The effects of 3-D printing parameters, impeller material of construction, and water/glycerin solution viscosities (1 cP to 12 cP) on mixing efficiency for solid (40 mesh sand)/liquid systems were investigated using a Box-Behnken experimental design and will be discussed. In addition, flow visualization experiments using complex impellers will be presented. The focus of this work is the development of 3-D printing rapid prototyping educational modules and laboratories that include design, manufacturing, statistical experimental design and data analysis to enhance creativity and critical thinking in the engineering curriculum while familiarizing students with new technologies and processes. Educational modules for sophomore level courses and laboratory experiments for senior level unit operations courses will be presented.