טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
M.Sc Thesis
M.Sc StudentMazor Lilach
SubjectAn Analytical, Numerical and Experimental Analysis of the
Generalized Equilibrium Flow in a Shear-Driven
Open Microchannel
DepartmentDepartment of Aerospace Engineering
Supervisor Dr. Ian Jacobi


Abstract

Increased interest in multiphased and shear-forced micro-flows has been emerging in recent times, due to their potential in the construction of superhydrophobic surfaces for drag reduction and protective coatings, as well as in applications of modern industry, such as micro-reactors, biomedical devices, DNA chips, fuel transport and lab-on-chip and heat exchanger technologies. In contrast to macroscopic systems, capillary flows in micro-fluidic channels are prone to be laminar and are dominated by surface tension and wall adhesion. A new generation of these materials incorporate a layer of immiscible fluid infused into the surface pattern to enhance its mechanical behavior. However, when such liquid-infused surfaces are exposed to an external shear flow, there is a risk of losing the infused liquid due to viscous drag at the interface, causing the surface to lose its advantageous properties. Thus, designing surface structures capable of retaining fluid under shear becomes important. \\


In this research, the steady state of capillary flow in a shear-forced open microchannel has been analyzed and studied analytically, numerically and experimentally. An analytical, one dimensional model was presented, as well a quasi three dimensional model which sought to understand the steady-state fluid retention in an open microfluidic channel under shear, as a function of the streamwise geometry of the groove. The results of this research verify and extend previous results regarding uniform capillary substrates to non-uniform geometries, and could ultimately lead to improved geometries and flow transport methods in micro-fluidic devices.