| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 238810 | Powder Technology | 2007 | 8 Pages |
The effects of wall slip of concentrated suspension melts in capillary flows were investigated at elevated temperature. The modeled material is a mixture of polymer EVA (Ethylene Vinyl Acetate) and non-colloidal spherical powder (glass microspheres) with mean particle size within 53∼63 μm. The effect of particle concentration on wall slip was studied experimentally in a capillary rheometer. For suspensions with different particle loadings (35%, 40%, and 45% by volume), the slip velocity Vs increased with an increase of particle concentration at the same testing temperature. A master slip curve can be obtained by plotting slip velocity versus the product of wall shear stress and square root of particle concentration. As such, a new particle concentration-dependent slip model is proposed. A theoretical approach coupled with the new slip model and flow equation is employed to characterize the flow behavior of concentrated suspension in a capillary rheometer, with reasonable agreement obtained with experimental observations.
Graphical abstractThe effects of wall slip of concentrated suspension melts in capillary flows were investigated experimentally and numerically. The suspension investigated is a mixture of EVA460 and non-colloidal glass microspheres. A master slip curve was obtained by plotting slip velocity versus the product of wall shear stress and the square root of particle concentration. A new particle concentration-dependent slip model is proposed.Figure optionsDownload full-size imageDownload as PowerPoint slide
