Water, viscosity

Viscosity is measured in poise. If a force of one dyne, acting on one cm, maintains a velocity of 1 cm/s over a distance of 1 cm, then the fluid viscosity is one poise. For practical purposes, the centipoise (cP) is commonly used. The typical range of gas viscosity in the reservoir is 0.01 - 0.05 cP. By comparison, a typical water viscosity is 0.5 -I.OcP. Lower viscosities imply higher velocity for a given pressure drop, meaning that gas in the reservoir moves fast relative to oils and water, and is said to have a high mobility. This is further discussed in Section 7. 

This parameter is important in the prediction of aguifer response to pressure drops in the reservoir. As for liquids in general, water viscosity reduces with increasing temperature. Water viscosity is in the order of 0.5 -1.0 cP, and is usually lower than that of oil. 

Examples of pressure drop variation for new resin as a function of flow rate and water temperature are shown in Eigure 5 for a standard styrenic strong acid cation exchanger. The lower pressure drop at the higher temperature is a reflection of water viscosity. 

The polymers exist in saline solution as tightly coiled chains and are readily adsorbed owing to relatively low solubiUty in hard water. Subsequent injection of soft, low salinity water uncoils the adsorbed polymer chains increasing water viscosity and reducing rock permeabiUty. This technology could also be used to reduce the permeabiUty of thief 2ones adjacent to injection wells. However, mechanical isolation of these 2ones may be necessary for cost-effective treatments. 

For this case, Steinmeyer s correlation becomes El-Shanawany, Eq. (14-199) predicts 76 microns with the viscosity term contributing less than 1 percent. With the same system and same L/G, but with an oil with 30 times water viscosity, Eq. (14-199) predicts 91 microns, with the viscosity term contributing 54 percent of the total. The measure values for water and oil cases were 70 and 95 microns, respectively. For comparison, Eq. (14-198) predicts 102 microns for the water case. 

Physical characteristics Molecular weight Vapour density Specific gravity Melting point Boiling point Solubility/miscibility with water Viscosity Particle size size distribution Eoaming/emulsification characteristics Critical temperature/pressure Expansion coefficient Surface tension Joule-Thompson effect Caking properties... 

Unless specifically identified otherwise, the BHP values read from a manufacturers performance curve represent the power only for handling a fluid of viscosity about the same as water and a specific gravity the same as water, i.e., SpGr = LG. To obtain actual horsepower for liquids of specific gravity other than 1.0, the curve values must be multiplied by the gravity referenced to water. Viscosity corrections are discussed in another section. Good design must allow for variations in these physical properties. 

As the temperature increases from ambient to the critical point, the electrolytic conductance of water rises sharply and is almost independent of the pressure. Macroscopically, this is due to the decrease in water viscosity over this range. The primary cause for the fall in viscosity is a disintegration of water clusters. 

A small sample of a coal slurry containing particles with equivalent spherical diameters from 1 to 500 pm is introduced into the top of a water column 30 cm high. The particles that fall to the bottom are continuously collected and weighed to determine the particle size distribution in the slurry. If the solid SG is 1.4 and the water viscosity is 1 cP, over what time range must the data be obtained in order to collect and weigh all the particles in the sample ... 

Viscosity of water Viscosity of permeate Diameter of protein molecule Operating pressure Porosity of gel... 

Viscosity is the ability of a fluid to resist deformation or flow, and is a measure of the tendency of a fluid to flow for example, molasses has a high viscosity relative to water. Viscosity is highly temperature dependent and has common units of cen-tipoise (cP). Water has a viscosity of 1.00 cP at 20°C, whereas carbontetrachloride has a viscosity of 0.97 cP at 20°C. Therefore, the two fluids will physically flow about the same. However, with respect to flow through porous media, surface tension is extremely important. 

Note. Noble gas radius from Zhang and Xu (1995). Molecular diffusivity from Jahne et al. (1987) except for Ar (Cussler, 1997). For SFe, the radius is based on S-F bond length of 1.56 A plus the radius of F- (1.33 A), and the diffusivity is from King and Saltzman (1995). The jumping distance is calculated from Equation 3-136e using pure water viscosity of 0.89 mPa s at 25°C. 

Calculate the power requirements, with and without aeration, of a 1.5 m-diameter stirred tank, containing water 1.5 m deep, equipped with a six-blade Rushton turbine that is 0.5 m in diameter d, with blades 0.2.5 d long and 0.2 d wide, operating at a rotational speed of 180 rpm. Air is supplied from the tank bottom at a rate of 0.6 m min C Operation is at room temperature. Values of water viscosity = 0.001 kg m and water density p = 1000 kg m... 

A 30 cm-diameter bubble column containing water (clear liquid height 2 m) is aerated at a flow rate of 10 m h . Estimate the volumetric coefficient of oxygen transfer and the average bubble diameter. The values of water viscosity = 0.001 kg m s , density p = 1000 kgm , and surface tension cr = 75 dyne cm" can be used. The oxygen diffusivity in water is 2.10 X 10 ... 

Water flowrate, bpd Water viscosity, ip Oil droplet diameter, micron Effective length in which separation occurs, ft Difference in specific gravity between oil and water... 

Oil and Water Viscosity. These data are used in computing vertical rising velocity of oil droplets in water. It has an important bearing in deciding the layout of coalescing media inside the equipment and on relative paths of oil and water. 

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