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1. Transient shear-jammed clusters in shear-thickening suspensions

   https://doi.org/10.1122/8.0000958  

   Moghimi, Esmaeel; Blair, Daniel L; Urbach, Jeffrey S (May 2025, Journal of Rheology)

   Dense particulate suspensions demonstrate a significant increase in average viscosity beyond a material-specific critical shear stress. Here, we analyze the steady-state structure of a suspension of monodisperse silica microspheres in the shear-thickening regime. Using dynamic measurement of boundary stress, we show that the flow is characterized by a cluster of high-stress fronts that propagate in the flow direction at a speed of 1/2 relative to the top plate of the rheometer. We apply high-speed line scan imaging to reveal dramatic fluctuations in particle speed, ordering, and concentration associated with the fronts and show that the structure is consistent with transiently jammed networks that contain high interparticle stresses that percolate across the rheometer gap, but which are present only briefly during the passage of the high-stress fronts. 

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2. Cyclic Direct Simple Shear tests - Effect of static shear stress

   https://doi.org/10.17603/ds2-q3fz-kq91  

   Lbibb, Sarra; Manzari, Majid (November 2022, Designsafe-CI)

   The stress-strain behavior and liquefaction strength of Ottawa F65 sand was investigated through an extensive series of cyclic direct simple shear (CDSS) tests. The study quantified the effects of static shear stress on the cyclic strength of Ottawa F65 sand. The database of CDSS tests was used to develop an Artificial Neural Networks model to predict Ottawa F65 cyclic strength. 

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3. Thermohaline‐Shear Instability

   https://doi.org/10.1029/2018GL081009  

   Radko, Timour (January 2019, Geophysical Research Letters)

   Abstract This study presents the linear theory of thermohaline‐shear instability, which is realized in oceanic flows that are dynamically and diffusively stable. The framework is based on the unbounded Couette model, which makes it possible to decouple the destabilizing effects of spatially uniform shear from instabilities caused by the presence of inflection points in velocity profiles. The basic state is assumed to be time dependent, which reflects the role of internal waves in controlling fine‐scale shear. Linear stability analysis suggests that conditions for thermohaline‐shear instability are met in most ocean regions where temperature and salinity concurrently increase downward. We conclude that thermohaline‐shear instability represents a plausible mechanism for the initiation of active diffusive convection, which, in turn, is essential for the formation of thermohaline staircases and maintenance of double‐diffusive interleaving. 

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4. Enhancing shear thickening

   https://doi.org/10.1103/PhysRevFluids.2.033301  

   Madraki, Yasaman; Hormozi, Sarah; Ovarlez, Guillaume; Guazzelli, Élisabeth; Pouliquen, Olivier (March 2017, Physical Review Fluids)
5. Effect of Unidirectional Vertical Wind Shear on Tropical Cyclone Intensity Change—Lower‐Layer Shear Versus Upper‐Layer Shear

   https://doi.org/10.1029/2019JD030586  

   Fu, Hao; Wang, Yuqing; Riemer, Michael; Li, Qingqing (June 2019, Journal of Geophysical Research: Atmospheres)

   Abstract In this study, a quadruply nested, nonhydrostatic tropical cyclone (TC) model is used to investigate how the structure and intensity of a mature TC respond differently to imposed lower‐layer and upper‐layer unidirectional environmental vertical wind shears (VWSs). Results show that TC intensity in both cases decrease shortly after the VWS is imposed but with quite different subsequent evolutions. The TC weakens much more rapidly for a relatively long period in the upper‐layer shear than in the lower‐layer shear, which is found to be related to the stronger storm‐relative asymmetric flow in the middle‐upper troposphere and the larger vertical vortex tilt in the former than in the latter. The stronger storm‐relative flow in the former imposes a greater ventilation of the warm core in the middle‐upper troposphere, leading to a more significant weakening of the storm. The storm in the lower‐layer shear only weakens initially after the VWS is imposed but then experiences a quasi periodic intensity oscillation with a period of about 24 hr. This quasi periodic behavior is found to be closely related to the boundary layer thermodynamic “discharge/recharge” mechanism associated with the activity of shear‐induced outer spiral rainbands. There is no significant intensity oscillation for the storm embedded in the upper‐layer shear, even though outer spiral rainbands develop quasi periodically also. The boundary layer inflow is very weak in that case and the low equivalent potential temperature air induced by downdrafts in outer spiral rainbands therefore cannot penetrate into the inner core but remains in the outer region. 

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