دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: the resistance to initial flow, or the stress required to start fluid movement. This resistance is caused by electrical charges located on or near the surfaces of the particles. The values of the yield point and thixotropy, respectively, are measurements of the same fluid properties under dynamic and static states. The Bingham yield value, reported in pounds/100 square foot, is determined from a directindicating viscometer by subtracting the plastic viscosity from the 300-rpm reading. Also called yield point.

Also called movable shear stress. The viscosity dont change along with the shear stress when shear stress arrive a given value,now shear stress and rate of shearing present direct ratio relation, the value of crossing point of this direct ratio relation

the critical shear stress that must be exceeded before flow can be initiated.

stream function or value of a streamline.

the compressibility correction index used in the ideal gas law. Z = Vactual / V ideal

The filtration value of the crossing point of the direct ration relatio line and the filtration value line is called zero error.

a brine made of salts of zinc, usually very dense.

n: (ZnCI2) a very soluble salt used to increase the density of water to points more than double that of plain water. Normally added to a system first saturated with calcium chloride.

A very weak base, ZnO, which can be used as a sulfide scavenger in oil-base or synthetic-base muds.