Nano Science and Technology InstituteNano Science and Technology Institute
Nano Science and Technology Institute 2005 NSTI Nanotechnology Conference & Trade Show
Nanotech 2005
Bio Nano 2005
Business & Investment
Nano Impact Workshop
Program
Sessions
Sunday
Monday
Tuesday
Wednesday
Thursday
Index of Authors
Index of Keywords
Keynote Presentations
Confirmed Speakers
Participating Companies
Industry Focus Sessions
Nanotech Expo
Special Symposia
Conferences
Sponsors
Exhibitors
Venue 2005
Organization
Press Room
Subscribe
Site Map
Nanotech 2005 At A Glance
Nanotech Proceedings
Nanotechnology Proceedings
Global Partner
nano tech
Supporting Organizations
Nanotech 2005 Supporting Organization
Media Sponsors
Nanotech 2005 Medias Sponsors
Event Contact
696 San Ramon Valley Blvd., Ste. 423
Danville, CA 94526
Ph: (925) 353-5004
Fx: (925) 886-8461
E-mail:
 
 

Thermal Modulation and Instability of Viscous Microjets

E.P. Furlani
Eastman Kodak Company, US

Keywords:
microjet instability, marangoni effect, surface tension, thermal modulation

Abstract:
Liquid microjets are inherently unstable and can be broken into droplets by various means including the modulation of pressure, velocity, and/or fluid properties. In this presentation we discuss the controlled breakup of viscous microjets via thermal modulation of surface tension. Such modulation can be implemented using CMOS/MEMS technology by integrating resistive heating elements into the orifice manifold surrounding each orifice, as depicted in Fig. 1. When the heating elements are pulsed in a time-wise periodic fashion, the thermal energy they produce is imparted to the surface of the microjet as it leaves the orifice. This energy is carried downstream by the jet velocity, and produces a time-dependent spatially periodic variation of surface tension along the jet that causes breakup and drop formation (Figs. 1 and 2). Using this method, microfluidic devices can be fabricated with thousands of functional microjets, each of which can be individually modulated to produce steady steams of picoliter-sized droplets. Moreover, these devices can operate at kilohertz frequency rates achieving unprecedented speed and versatility of droplet generation for applications such as inkjet prining.1, 2 In this presentation, we discuss theoretical models for predicting the instability of viscous microjets that are subjected to a thermally induced modulation of surface tension. We present analytical formulas for predicting the free-surface, velocity, and pressure within the jet. We use these to understand the instability physics, and to estimate the time-to-breakup Tb as a function of the modulation wavelength, fluid properties, and system parameters (Fig. 3). We also present numerical models for more accurate predictions of pinch-off and satellite formation.

Back to Program

Sessions Sunday Monday Tuesday Wednesday Thursday Authors

Nanotech 2005 Conference Program Abstract

 
Gold Sponsors
Nanotech Gold Sponsors
Silver Sponsors
Nanotech Silver Sponsors
Gold Key Sponsors
Nanotech Gold Key Sponsors
Nanotech Ventures Sponsors
Nanotech Ventures Sponsors
Sponsors
Nanotech Sponsors
News Headlines
NSTI Online Community
 
 

© Nano Science and Technology Institute, all rights reserved.
Terms of use | Privacy policy | Contact