دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: the viscosity of a drilling fluid as measured with a directindicating, or rotational, viscometer.

n: The viscosity a fluid appears to have on a given instrument at a stated rate of shear. It is a function of the plastic viscosity and the yield point. The apparent viscosity in centipoises, as determined by the direct-indicating viscometer, is equal to the

the viscosity at a given shear rate and a given temperature.

a rheological model used to describe flow in some fluids. Bingham fluids have a linear shear stress, shear-rate behavior after an initial shear-stress boundary has been crossed. Plastic viscosity or PV is the slope of the line. Yield Point is the threshol

n pi: in drilling-fluid terminology, a chemical is any material that produces changes in the viscosity, yield point, gel strength, fluid loss, and surface tension.

n: In drilling-fluid terminology, a chemical is any material that produces changes in the low-shear-rate viscosity, yield point, gel strength, fluid loss, pH, or surface tension.

n: a dilatant. or inverted plastic, fluid is usually made up of a high concentration of well-dispersed solids that exhibits a nonlinear consistency curve passing through the origin. The apparent viscosity increases instantaneously with increasing rate of shear. The yield point, as determined by conventional calculations from the direct-indicating viscometer readings, is negative;however, the true yield point is zero.

n: This fluid is one of non-Newtonian flow patterns whose unique feature
is that once the fluid is subjected to force,it will start flowing without any gel strength.




a well dispersed, high solids content liquid that has very high apparent viscosity with any applied shear.

n: commonly called a V-G meter: A rotational device powered by means of an electric motor or handcrank. Used to determine the apparent viscosity, plastic viscosity, yield point, and gel strengths of drilling fluids.

n: a fluid in which the viscosity remains constant for all rates of shear if constant conditions of temperature and pressure are maintained. Most drilling fluids behave as non-Newtonian fluids, as their viscosity is not constant but varies with the rate of shear.

n: the basic and wsimplest fluids from the standpoint of viscosity consideration in which the shear force is directly proportional to the shear rate. These fluids will immediately begine to move when a pressure or force in excess of zero is applied. examples

a fluid whose shear force and response is directly proportional to shear rate. Yield point is zero.

n: a complex, non-Newtonian fluid in which the shear force is not proportional to the shear rate. Most drilling muds are plastic fluids.

n: a complex, non-newtonian fluid in which the shear force is not proportional to the shear rate. A definite pressure is required to start and maintain movement of liquid. Plug flow is the initial type of flow and only occurs in plastic fluids. Most drilling

a complex, non-Newtonian fluid whose shear force is not proportional to the shear rate. Pressure is necessary to start circulation of the static fluid. Main low rate flow is plug flow. Yield point is greater than zero.

n: instrument used for assessing mud properties that records values for both plastic viscosity and yield point.

materials that change the relationship between solids and viscosity of a fluid to lower the gel strength, yield point, yield strength or viscosity as it affected by solids.

n: a device used to determine the viscosity of a substance. Also called a viscosimeter.

n: Commonly called a V-G meter.The instrument is a rotational-type device powered by means of an electric motor or handcrank and is used to determine the apparent viscosity,plastic viscosity,yield point and gel strengths of drilling fluids.The usual speed