wall friction

wall friction

[′wȯl ‚frik·shən]
(fluid mechanics)
The drag created in the flow of a liquid or gas because of contact with the wall surfaces of its conductor, such as the inside surfaces of a pipe.
References in periodicals archive ?
In general, in an isothermal system, the flow pattern of polymeric melts flowing through an LME channel is controlled by the geometry constraints, inlet flow rate and wall friction. Because the geometry of the LME channel has been fixed, the inlet flow rate and wall friction were selected for further study.
In the rheological evaluation of the powders, the following parameters were determined: principal consolidation stress and unconfined failure strength, bulk densities, effective angles of internal friction and wall friction, through the device Powder Flow Test (PFT) from Brookfield Engineering Laboratories.
The commonly used wall pressure coefficients are the Rankine active earth pressure coefficient [kappa] = (1 - sin [psi])/(1+sin [psi]) [27], the static earth pressure coefficient k = 1 - sin [psi] [28], the modified static earth pressure coefficient, and the wall pressure coefficient considering wall friction [29-31].
Some of these properties include bulk density, tap density, compressibility, particle size and size distribution, fluidization, flowability, cohesion, angle of internal friction, and angle of wall friction. Unlike most other researchers, Dr.
In sections on functional and electronic materials, high-performance structural material, and materials processing technology, 28 papers discuss such topics as the controllable synthesis of mono-dispersed metal oxide nanostructures with a solvothermal route and their catalytic properties, hydration mechanisms of Portland cement with magnesium slag, the mesoscopic simulation analysis of the influence of die wall friction on the compression process of powder particles, and the effect of coiling temperature and cold rolling reduction on the planar anisotropy of low-carbon steel alloyed with titanium.
Shear cell technology provides the solution through the use of an annular shear cell and a wall friction lid.
Evaluation of the wall friction coefficient for a sinusoidal corrugated wall is determined as:
The FT4 Powder Rheometer from Freeman Technology is a universal powder tester--three instruments in one, combining the proprietary blade methodology for measuring flow energy with a range of shear cells, wall friction modules and other accessories for measuring bulk properties.
For example, it defies common sense that the wall friction accelerates a subsonic compressible flow in a constant-area duct with or without heating.
The tests were conducted on smooth (wall friction of pile was low) and rough (fine sand was pasted around the pile by adhesive), single piles in dense ([D.sub.r] = 75%), and loose ([D.sub.r] = 30%) sand.