Conversion kinematic viscosity

A number of arbitrary viscosity units have also been used. The most common has been the Saybolt Universal second (SUs) which is simply the time in seconds required for 60 mL of oil to empty out of the cup in a Saybolt viscometer through a carefully specified opening. Detailed conversion tables appear in ASTM D2161, approximation of kinematic viscosity V in mm /s(= cSt) can be made from the relation shown in equation 8 ... 

The Saybolt universal viscosity equivalent to a given kinematic viscosity varies slightly with the temperature at which the determination is made because the temperature of the calibrated receiving flask used in the Saybolt method is not the same as that of the oil. Conversion factors are used to convert kinematic viscosity from 2 to 70 cSt at 38°C (100°F) and 99°C (210°F) to equivalent Saybolt universal viscosity in seconds. Appropriate multipliers are listed to convert kinematic viscosity over 70 cSt. For a kinematic viscosity determined at any other temperature, the equivalent Saybolt universal value is calculated by use of the Saybolt equivalent at 38°C (100°F) and a multiplier that varies with the temperature ... 

Viscosity, kinematic, ASTM Designation D 445-39T. Conversion to Saybolt Universal viscosity, ASTM Designation D 446-39. Kinematic viscosity index, ASTM Designation D 567-40T. APIgravity, ASTM Designation D 287-39. Pour point, ASTM Designation D 97-39. Unsulfonated residue, ASTM Designation D 483-40. 

The Saybolt universal viscosity (SUS) equivalent to a given kinematic viscosity varies slightly with the temperature at which the determination is made because the temperature of the calibrated receiving flask used in the Saybolt method is not the same as that of the oil. Conversion factors are used to convert... 

Standard Practice for Conversion of Kinematic Viscosity to Saybolt Universal Viscosity or Say-bolt Furol Viscosity, ASTM Designation D 2163-93, American Society for Testing and Materials Philadelphia, PA, July, 1993. 

Table 1-1 Conversion Factors for Viscosity, Kinematic Viscosity, and Activation Energy of Fiow...

The classification criteria refer to kinematic viscosity. The following provides the conversion between dynamic and kinematic viscosity ... 

Hydrazine has been studied extensively for use in monopropellant thrusters for space flights of long duration. Thrusters are used or altitude control of communication satellites. Here the decomposition of hydrazine over a packed bed of alumina-supported iridium catalyst is of interest. " In a proposed study, a 2% hydrazine in 98% helium mixture is to be passed over a packed bed of cylindrical particles 0.25 cm in diameter and 0.5 cm in length at a gas-phase velocity of 15m/s and a temperature of 750 K. The kinematic viscosity of helium at this temperature is 4.5 X 10 nF/s. The hydrazine decomposition reaction is believed to be externally mass transfer-limited under these conditions. If the packed bed is 0.05 m in length, what conversion can be expected Assume isothermal operation. 

The constant r in the equation is called the y/scosity coefficient or dynamic viscosity. Its unit in the Sf system is Pa s (for conversion of units, 1 poise = 0.1 Pa s = = 1 dPa s). The reciprocal value of dynamic viscosity is called fluidity (fluidity coefficient). In hydrodynamics, frequent use is made of a quantity expressing the dynamic viscosity divided by density of the liquid and called kinematic viscosity... 

In the test, the time for a fixed volume of liquid to flow under gravity through the capillary of a calibrated viscometer under a reproducible driving head and at a closely controlled temperature is measured in seconds. The kinematic viscosity is the product of the measured flow time and the calibration constant of the viscometer. Conversion of the kinematic viscosity in centistokes (cSt) at any temperature to Saybolt Universal viscosity in Saybolt Universal seconds (SUS) at the same temperature and for converting kinematic viscosity in centistokes at 122 and 210°F to Saybolt Furol viscosity in Saybolt Furol seconds (SFS) at the same temperatures (ASTM D-2161) is avaibale through formulae. 

Although it is considered a technical advantage to specify kinematic viscosity, the conventional viscometers are still in wide use and it may be convenient, or even necessary, to be able to convert viscosities from one system to another. Provision is made (ASTM D-2161) for the conversion of kinematic viscosity to Saybolt Universal and Furol viscosity and (in IP standards) for conversion to Redwood viscosity ... 

ASTM Method D 2161-56, Conversion of Kinematic Viscosity Universal Viscosity or to Saybolt Furol Viscosity, ASTM Book, Part 17—Petroleum Products, American Society for Testing and Materials, Philadelphia. 

Kinematic viscosity. The ratio of the absolute viscosity to the density of a fluid, jijp, is often useful. This property is called the kinematic viscosity and designated by V. In the SI system, the unit for v is square meters per second. In the cgs system, the kinematic viscosity is called the stoke (St), defined as 1 cm s. The fps unit is square feet per second. Conversion factors are... 

Conversion factors for mass, density, pressure, energy, specific energy, specific heat, thermal conductivity, dynamic viscosity, and kinematic viscosity in different systems of units are also given in Chap. 2 (Tables 2.1-2.9). 

TABLE 2.9 Conversion Factors for Units of Kinematic Viscosity... 

ASTM Designation (1993) D 2163-93. Standard Practice for Conversion of Kinematic Viscosity to Saybolt Universal Viscosity or Saybolt Eurol Viscosity, American Society for Testing and Materials, Philadelphia, PA, July, 1993. Bennett, LL, Bishop, J.L., and Wulfinghoff, M.F. (1968) Practical Emulsions, vol. 1, 2, Chemical Publishing Co., New York. 

Figure A-1 Conversions among systems of units for kinematic viscosity for liquids.

Estimate the hydraulic diameter of a square microchannel reactor to avoid mass transfer influence supposing segregated laminar flow (/ e<10). The mean inlet concentration of the reactants is Cj 0 = 2 q = 0.4 mol 1 and the reactor is operated at 303 and 323 K. Both reactants are fed to a T-mixer separately. The diffusion coefficient is = 10 m s , the kinematic viscosity is V = 10 m s . Determine the residence time for a conversion of X = 0.9. Solution ... 

Other conversion factors for viscosity are given in Appendix A.l. Sometimes the viscosity is given as pjp, kinematic viscosity, in m /s orcm /s, where p is the density of the fluid. 

THE PROBLEM An undivided rotating cylinder reactor is operated in a batch recycle loop to process a batch of 0.2 m every 8 hours. The cylinder is 1 m long and 0.1 m in radius the interelectrode gap is 0.05 m. The reaction takes place under mass transfer limiting conditions. If the maximum rotation speed of the cylinder is 150 rpm, determine whether the operation is feasible if the required conversion is to be 80%. If so, what is the required rotation speed and what is the maximum conversion possible Assume that axial flow in the reactor can be ignored. The kinematic viscosity v is 1.1 X 10" m /s and the Schmidt number Sc is 2500. 

The oils and the biodiesel products of the transesterification procedures are mainly characterized by nuclear magnetic resonance ( H-NMR) and gas chromatography (GC) techniques. The H-NMR technique provides chemical characteristics of the oils, fats, and products and the conversion degrees of the transesterification procedures. GC allows a more accurate characterization of the molecular species involved in the transesterification procedure. Additionally, the Analysis Biodiesel Protocol for the characterization of the methyl or ethyl biodiesel must include information of the following physicochemical techniques kinematic viscosity, density, flash point, cloud point, pour point, cold filter plugging point, free and total glycerol, ethanol residue, sulfur content, acid number, oxidative stability, and refractive index. 

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