Viscometers moving body

Viscometers may be separated into three main types capillary, rotational, and moving body. There are other kinds, usually designed for special apphcations. For any given type there usually is a choice of several different instmments. The choice depends on the particular requirements of the investigator and the price range. 

Moving Body Viscometers. In moving body viscometers, the motion of a ball, bubble, plate, needle, or rod through a material is monitored. 

In the Irvine-Park falling needle viscometer (FNV) (194), the moving body is a needle. A small-diameter glass or stainless steel needle falls vertically in a fluid. The viscous properties and density of the fluid are derived from the velocity of the needle. The technique is simple and useflil for measuring low (down to lO " ) shear viscosities. The FNV-100 is a manual instmment designed for the measurement of transparent Newtonian and non-Newtonian... 

Moving body viscometers, 21 737-739 Moving-hearth incinerators, 13 177 MOX fuel, 19 686 Moxifloxacin, 21 224, 228, 231 Moxifloxacin, 3 25, 29 Mozley multigravity separators (MGS),... 

Table 8. Selected Commercial Moving Body Viscometers...

Surface viscosity can be measured with a canal viscometer or with a torsion viscometer. The former instrument measures the flow of the film through a slit in a beurier on a film balance the latter, the damping caused by the presence of a film on a body moving in the surface of the liquid. Interpretation of measurements on films with a constant viscosity is difficult and would be more so in the presence of viscosity changes caused by reaction. 

The torsional pendulum of a dense disk moving slowly in a viscous medium has been developed by J. Kestin and co-workers about 1980 to measure simultaneously the density and the viscosity of the fluid [5.11]. This work was based on a couple of papers reporting on oscillating body viscometers using cups, spheres, cylinders, etc. published already in the period 1930-1960 [5.12]. Today pendulum viscosimeters are used to measure the viscosity of both gases, liquids, and even molten metals and salts at extreme temperatures (Ir(liquid melting state) 2,800 K) and pressures (100 MPa), [5.13-5.15]. 

---