Atomization and Sprays Journal of the International Institutes for Liquid Atomization and Spray Systems

ISSN for PRINT: 1045-5110

For Online Access

Best Paper Award Selection - Editorial Board Site

2003, Volume13

Issue 2&3

218 pages

DOI: 10.1615/AtomizSpr.v13.i23

Issue price - $150.00

Thomas J. Hartranft
Gas Dynamics Laboratory, Mechanical & Nuclear Engineering Department, Penn State University, University Park, Pennsylvania, USA

Gary S. Settles
Gas Dynamics Laboratory, Mechanical & Nuclear Engineering Department, Penn State University, University Park, Pennsylvania, USA

An experimental investigation is made of the sheet atomization of dilute concentrations of flexible 9 ґ 10⁶ molecular-weight nonionic polyacrylamide in glycerin-thickened aqueous solutions. These solutions are sprayed through a single fan male at pressures of 1.4-21 MPa. The original molecular weight and extensional viscosity are significantly degraded at all pressures by the strain rates imposed by the spray system and nozzle. In spite of this degradation, however, the sheet breakup features are nonetheless visibly altered by these dilute polymer concentrations. From our results, the physics of polymeric solution sheet breakup appears to be a combination of destabilizing and stabilizing extensional viscosity effects. The destabilizer is the amplification of sheet waves at the nozzle exit, which leads to decreased sheet breakup lengths, whereas the stabilizer is the extensional viscosity-induced increase of wavelength. Implications of these results are considered in terms of rheological instruments and industrial applications, especially "airless" spray painting.

DOI: 10.1615/AtomizSpr.v13.i23.30 Download article, 31 pages

Article price - $35.00

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