Effects of Variable Pressure on Newtonian and Non-Newtonian Microfluidic Flow

School Name

Governor's School for Science & Mathematics

Grade Level

12th Grade

Presentation Topic

Engineering

Presentation Type

Mentored

Mentor

Mentor: Xiangchun Xuan , Clemson University

Abstract

In this experiment, the vortical flow effects caused by variable pressure were investigated in microfluids, both Newtonian and non-Newtonian, as they passed through a constriction in a microchannel. It is becoming increasingly important for us to study such interactions as the field of microfluidics expands. Biomedical researchers simulating blood flow in a lab-on-a-chip, or even product designers in the inkjet printing industry could benefit by knowing that these particular interactions occur, as a vortex appearing could cause unforeseen issues in a micro-scale environment like a capillary or tube of ink. Knowing when and why these vortices occur can allow such researchers to avoid or utilize them. It is also important to compare and contrast the flows of Newtonian and non-Newtonian fluids, the latter of which consists of a wide variety of fluids that all behave differently depending on the situation. Through studies such as these, the practicality of using either fluid at the microscopic scale can be further assessed and their unique advantages fully harnessed according to the needs of their application. This experiment was approached by fabricating microchannels, each containing a constriction where channel width abruptly decreased by 90% for a short length, and using a syringe pump to push samples of both fluid types through it at incrementally increasing pressures. It was shown that regardless of fluid type, there is a positive correlation between flow pressure and vortex dimension. In addition, several qualitative differences were observed between the Newtonian and non-Newtonian vortices.

Location

Wall 223

Start Date

3-25-2017 12:00 PM

Presentation Format

Oral and Written

Group Project

No

COinS
 
Mar 25th, 12:00 PM

Effects of Variable Pressure on Newtonian and Non-Newtonian Microfluidic Flow

Wall 223

In this experiment, the vortical flow effects caused by variable pressure were investigated in microfluids, both Newtonian and non-Newtonian, as they passed through a constriction in a microchannel. It is becoming increasingly important for us to study such interactions as the field of microfluidics expands. Biomedical researchers simulating blood flow in a lab-on-a-chip, or even product designers in the inkjet printing industry could benefit by knowing that these particular interactions occur, as a vortex appearing could cause unforeseen issues in a micro-scale environment like a capillary or tube of ink. Knowing when and why these vortices occur can allow such researchers to avoid or utilize them. It is also important to compare and contrast the flows of Newtonian and non-Newtonian fluids, the latter of which consists of a wide variety of fluids that all behave differently depending on the situation. Through studies such as these, the practicality of using either fluid at the microscopic scale can be further assessed and their unique advantages fully harnessed according to the needs of their application. This experiment was approached by fabricating microchannels, each containing a constriction where channel width abruptly decreased by 90% for a short length, and using a syringe pump to push samples of both fluid types through it at incrementally increasing pressures. It was shown that regardless of fluid type, there is a positive correlation between flow pressure and vortex dimension. In addition, several qualitative differences were observed between the Newtonian and non-Newtonian vortices.