Suscripción a Biblioteca: Guest
Portal Digitalde Biblioteca Digital eLibros Revistas Referencias y Libros de Ponencias Colecciones
Interfacial Phenomena and Heat Transfer
ESCI

ISSN Imprimir: 2169-2785
ISSN En Línea: 2167-857X

Open Access

Interfacial Phenomena and Heat Transfer

DOI: 10.1615/InterfacPhenomHeatTransfer.2013010246
pages 273-287

EFFECTS OF PSEUDOPLASTICITY ON SPREAD AND RECOIL DYNAMICS OF AQUEOUS POLYMERIC SOLUTION DROPLETS ON SOLID SURFACES

Vishaul Ravi
Thermal-Fluids and Thermal Processing Laboratory, Department of Mechanical and Materials Engineering, University of Cincinnati, Cincinnati, Ohio, 45221-0072, USA
Milind A. Jog
Thermal-Fluids and Thermal Processing Laboratory, Department of Mechanical and Materials Engineering, University of Cincinnati, 2600 Clifton Ave, Cincinnati, OH 45220, USA
Raj M. Manglik
Thermal-Fluids and Thermal Processing Laboratory, Mechanical and Materials Engineering, University of Cincinnati, 2600 Clifton Ave, Cincinnati, OH 45220, USA

SINOPSIS

The postimpact spreading and recoil behavior of millimeter-size liquid droplets of pure water, water−glycerol solution, and non-Newtonian aqueous solutions of medium-grade hydroxyl ethyl cellulose (HEC 250 MR) on dry horizontal hydrophobic (Teflon) and hydrophilic (glass) substrates is presented. The drop spread−recoil dynamics are captured using a high-speed high-resolution digital video recording and image processing. The non-Newtonian effects of aqueous polymeric solutions on postimpact spreading are contrasted with those for a water−glycerol solution with identical surface tension and zero-shear rate viscosity. For a broad range of drop Weber numbers (20 ≤ We ≤ 200), dynamic visualized records of impact, spreading, and recoil are presented along with their measured temporal variations in drop-diameter-scaled spread and film height. The shear-rate-dependent viscosity of the polymer solution is found to give rise to highly complex spread−recoil dynamics compared to Newtonian liquids. During initial spread, because the shear rate tends to be high, shear-thinning or pseudoplasticity effects manifest in polymer solution drops to alter their spread dynamics. Contrarily, during recoil their higher low-shear apparent viscosity tends to retard recoil and dampen shape oscillations. Shear-rate-dependent non-Newtonian behavior is further seen at low We (low shear rate during spreading), where the maximum spread of HEC solution droplets is comparable to that of high-viscosity water−glycerol solution, whereas at high We (high shear rate during spreading), their maximum spreads are closer to those of low-viscosity water droplets.


Articles with similar content:

ONSET OF NATURAL CONVECTION AND HEAT TRANSFER IN A LAYER OF WATER BELOW MELTING ICE
International Heat Transfer Conference 8, Vol.4, 1986, issue
Edgar R. F. Winter, Wolfram Englberger
EFFECTS OF LIQUID AND SURFACE CHARACTERISTICS ON OSCILLATION BEHAVIOR OF DROPLETS UPON IMPACT
Atomization and Sprays, Vol.24, 2014, issue 10
Rafael Sanchez, Hamza Surti, Darren Banks, Cynthia Ajawara, Guillermo Aguilar
RAYLEIGH−TAYLOR INSTABILITY IN TWO-FLUID AND STRATIFIED MEDIA
ICHMT DIGITAL LIBRARY ONLINE, Vol.0, 2012, issue
Sergey N. Yakovenko
RAYLEIGH−TAYLOR INSTABILITY IN TWO-FLUID AND STRATIFIED MEDIA
Computational Thermal Sciences: An International Journal, Vol.4, 2012, issue 5
Sergey N. Yakovenko
MEASUREMENT OF DYNAMIC SURFACE TENSION OF SUSPENSION SPRAYS BASED ON OSCILLATING JET TECHNIQUE
Atomization and Sprays, Vol.29, 2019, issue 1
Ghobad Amini, Amr Saleh, Ali Dolatabadi