Publication Date

2018-05-14

Document Type

Honors Project

Degree Name

Bachelor of Science

Department

Engineering

Advisors

Susannah V. Howe

Keywords

Thermal analysis, Computational fluid dynamics, Infrared imaging, ANSYS, Finite element analysis, Finite element method, ANSYS (Computer system), Thermal analysis-Computer programs

Abstract

Particle separation within a fluid based on characteristic properties such as size, density, and compressibility is a need in multiple applications including cell and gene therapy. FloDesign Sonics, a start-up company in Wilbraham, Massachusetts created a technology that uses acoustic fields to separate particles. The angled wave device (AWD) is a design FloDesign Sonics developed, which uses a transducer and reflector to create standing waves. When a fluid particle mixture is pumped into the device and passes through the acoustic field created by these standing waves, the particles are deflected into different outlet slots based on their size, density, and compressibility. To ensure accurate particle separation, parameters such as pressure, velocity, and temperature must remain constant over time. If any of these parameters are unsteady, the particles will not predictably deflect into outlet slots and the AWD will not accurately separate particles by their characteristic properties. In my Design Clinic team project, we designed, manufactured, and tested a modified AWD with attachments to address unsteady pressure and velocity in the system. My honors extension project examines the temperature changes within the system. After identifying the topic of my project, I defined the constraints of the project through better understanding the FloDesign Sonics AWD. The main source of temperature changes within the system is the transducer. The transducer heats up over time, which not only raises the possibility of inaccurate particle deflection, but also increases the risk of damaging the living cells that the AWD separates in cell and gene therapy applications. FloDesign Sonics’ devices currently have cooling loops that aim to reduce the temperature of the transducer, however, the liaisons at FloDesign Sonics reported that no thermal tests have been conducted to evaluate the current system. I conducted an Infrared Imaging Test, which examined the temperature within the main chamber of the AWD and the effects of the cooling loop on the system. I processed the data from the Imaging Test and determined the system takes approximately seven minutes after the transducer has reached its maximum temperature and the cooling loop is turned on for the temperature of the main chamber to reach a constant temperature. FloDesign Sonics’ current test procedure is to start taking data immediately after the cooling loop is turned on. So, the results of my Infrared Imaging Test will help ensure researchers wait for the main chamber temperature to reach a constant value before collecting data in future tests. While I was conducting my Infrared Imaging Test, I was also learning different finite element analysis (FEA) and computational fluid dynamics (CFD) analysis systems. FEA and CFD are tools which help us predict how a system will behave under specific conditions. The FloDesign Sonics AWD has intricate geometry and there are limitations to visualizing the thermal and fluidic system experimentally. FEA and CFD help researchers see how the system should behave at each point spatially within the device and over time. I wanted to use these tools to compare a CFD model to my experimental results from the Infrared Imaging Test to assess my experimental results. I used both ANSYS and COMSOL to run multiple simulations of a simplified AWD system, leaving out the cooling loop and leaving out fluid flow. Using a simplified model, the results could not be a good comparison for my Infrared Imaging Test results. However, through working with the different FEA and CFD analysis systems, I gained the knowledge necessary to offer various suggestions for future work. This report covers background on infrared imaging and the AWD system, the scope of the project, the thermal imaging portion and the FEA and CFD portion of the project, as well as future work and recommendations for FloDesign Sonics.

Rights

2018 Lisa H. Feiden. Access limited to the Smith College community and other researchers while on campus. Smith College community members also may access from off-campus using a Smith College log-in. Other off-campus researchers may request a copy through Interlibrary Loan for personal use.

Language

English

Comments

77 pages : color illustrations. Includes bibliographical references (page 24)

Share

COinS