Viscoplastic drop impact on thin films

Spreading of viscoplastic droplets

“…Previous experiments have been reported for the problem of viscoplastic droplet impact on solid surfaces (Luu & Forterre 2009; Saïdi, Martin & Magnin 2010; Luu & Forterre 2013; Blackwell et al. 2015; Sen, Morales & Ewoldt 2020) or fluid interfaces (Jalaal, Kemper & Lohse 2019 a ).…”

“…The final shape of the droplets is of particular importance in industrial processes such as 3-D printing, as it can determine the resolution of the printing process and the final quality of the product. Previous experiments have been reported for the problem of viscoplastic droplet impact on solid surfaces (Luu & Forterre 2009;Saïdi, Martin & Magnin 2010;Luu & Forterre 2013;Blackwell et al 2015;Sen, Morales & Ewoldt 2020) or fluid interfaces (Jalaal, Kemper & Lohse 2019a).…”

Thixotropic spectra and Ashby-style charts for thixotropy

“…We test two common yield-stress fluids: 4.0 wt% suspension of Laponite RD colloidal clay particles in water, which forms a sparse physical gel when dispersed, typically identified as a thixotropic material 16 ; and 1.0 wt% suspension of Carbopol 940 microgel particles in water, a model yield-stress fluid formed of jammed, swollen, crosslinked polyacrylic acid microgel particles, known to exhibit negligible thixotropy 33,34 . These suspensions were prepared using methods from the literature 35,36 . We also use step shear data for two model thixotropic yieldstress fluids from the open literature: 3.23 vol% carbon black suspensions in naftenic oil 27 , and 2.9 vol% fumed silica suspension in paraffin oil with PIB 37 .…”

Decoupled rolling, sliding and sticking of a viscoplastic drop on a superhydrophobic surface

“…Above all, a better understanding of the interaction of viscoplastic fluids with solid surfaces is critical in environmental situations as well as industries, such as coating, food processing, spraying, inkjet printing, lava flows and landslides. Therefore, many studies have been reported so far, regarding interfacial hydrodynamics such as wetting (Boujlel & Coussot 2013;Jalaal, Balmforth & Stoeber 2015;Jorgensen et al 2015;Varagnolo et al 2015), wall slip (Jalaal et al 2015;Varagnolo et al 2015;Zhang et al 2017Zhang et al , 2018 and drop impact (Luu & Forterre 2009;Oishi, Thompson & Martins 2019;Sen, Morales & Ewoldt 2020). However, the prediction of viscoplastic fluid motions still remains challenging due to the complex nature of the problem with many related factors including yield stress, surface adhesion, surface tension, shear-dependent viscosity, etc.…”

“…2015; Zhang et al. 2017, 2018) and drop impact (Luu & Forterre 2009; Oishi, Thompson & Martins 2019; Sen, Morales & Ewoldt 2020). However, the prediction of viscoplastic fluid motions still remains challenging due to the complex nature of the problem with many related factors including yield stress, surface adhesion, surface tension, shear-dependent viscosity, etc.…”