Origin of apparent viscosity in yield stress fluids below yielding
نویسندگان
چکیده
منابع مشابه
Origin of apparent viscosity in yield stress fluids below yielding
For more than 20 years it has been debated if yield stress fluids are solid below the yield stress or actually flow; whether true yield stress fluids exist or not. Advocates of the true yield stress picture have demonstrated that the effective viscosity increases very rapidly as the stress is decreased towards the yield stress. Opponents have shown that this viscosity increase levels off, and t...
متن کاملAdhesion of yield stress fluids
The different regimes of flow when separating two solid rough surfaces in contact via a layer of a simple yield stress fluid are identified. Generic scalings for the adhesion energy and for the geometrical characteristics of the final deposits (after separation) as a function of the initial aspect ratio of the sample are found. We show that there is a strong pinning effect which might be at the...
متن کاملShear-induced sedimentation in yield stress fluids
Stability of coarse particles against gravity is an important issue in dense suspensions (fresh concrete, foodstuff, etc.). On the one hand, it is known that they are stable at rest when the interstitial paste has a high enough yield stress; on the other hand, it is not yet possible to predict if a given material will remain homogeneous during a flow. Using MRI techniques, we study the time evo...
متن کاملStructure-Enhanced Yield Stress of Magnetorheological Fluids
The yield stress of magnetorheological ͑MR͒ fluids depends on the induced solid structure. Since thick columns have a yield stress much higher than a single-chain structure, we improve the yield stress of MR fluids by changing the fluid microstructure. Immediately after a magnetic field is applied, we compress the MR fluid along the field direction. Scanning electron microscopy images show that p...
متن کاملModified Newton Solver for Yield Stress Fluids
Abstract. The aim of this contribution is to present a new Newton-type solver for yield stress fluids, for instance for viscoplastic Bingham fluids. In contrast to standard globally defined (‘outer’) damping strategies, we apply weighting strategies for the different parts inside of the resulting Jacobian matrices (after discretizing with FEM), taking into account the special properties of the ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: EPL (Europhysics Letters)
سال: 2009
ISSN: 0295-5075,1286-4854
DOI: 10.1209/0295-5075/87/38004