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Capstone (Math 451H) Spring 2007:****
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Instability of
a Fluid Strip**

Department of Mathematical Sciences

Instability of a fluid strip

Jamila Hedhli

Joe Brachocki

Sanjay Muddam

Daniel Fong

Assistant: Nebo Murisic

Instructor: Lou Kondic

Department of Mathematical Sciences, New Jersey Institute of
Technology

Waves on the surface of a thin liquid film have intrigued
researchers for several years. Numerous experimental and modeling
studies have been reported.

Due to the presence of the free surface, governing non-linear Navier-Stokes

(N-S) equations are considerably difficult to analyze. Thus effort
was made to describe these surface waves using low-dimensional
models derived from the N-S equations. Our project is composed of
three parts. Experimentally we use a goniometer to record the
profile of a strip flowing down an inclined and inverted surfaces,
using two types of solids. Computationally, we solve the PDE for the
fluid height for the two types of solids. Theoretically, we discuss
the similarities and differences between the waves observed on
falling films, and the ones present in the case of the flow down an
inverted surface.

**Powerpoint
Presentation Link **