What do you calculate from viscometer?
What do you calculate from viscometer?
You can measure the viscosity of a liquid by measuring the velocity of a sphere as it falls through the liquid. The velocity of the sphere, combined with the relative densities of the sphere and the liquid, can be used to calculate the viscosity of the liquid.
How do you measure viscosity using a falling sphere viscometer?
Measure the diameter of the sphere. Measure it multiple times to gain an accurate measurement and to determine the relative error in the measurement. The viscosity can be determined by measuring the position of the sphere as a function of time as it settles through the unknown fluid.
How is viscometer constant calculated?
The calibration constant for the viscometer at 100°C can now be calculated using the same equation. Viscometer No. (cP) multiply the kinematic viscosity in mm2 /s( cSt) by the density in grams per milliliter.
How do you find the viscosity of a viscometer?
To obtain kinematic viscosity (v = ny), multiply the measured flow time (tf) by the so-called capillary constant (KC). This constant needs to be determined for each capillary by calibrating the capillary, i.e. by measuring a reference liquid of known viscosity.
How does a falling sphere viscometer work?
The basic concept is to measure the elapsed time required for the ball to fall under gravity through a sample-filled tube inclined at an angle*. The tube is mounted on a pivot bearing which quickly allows rotation of the tube 180 degrees, thereby allowing a repeat test to run immediately.
Why should the viscometer be dried before the measurements are done?
Drying the viscometer after cleaning Highly volatile solvents are recommended for cleaning since any remaining solvent will evaporate quickly after the sample has been flushed from the viscometer.
What is a falling sphere viscometer?
A falling-sphere viscometer is a device used to measure the viscosity of a fluid by measuring the time required for a spherical ball to fall a certain distance under gravity through a tube filled with the fluid whose viscosity is to be determined.
What is the principle of viscometer?
These viscometers use the principle of ‘rotational viscometry’, i.e. their measurement of product viscosity is based upon immersing a specifically selected spindle within a sample of the product followed by measurement of the torque required to rotate the spindle at a set speed whilst immersed within the product sample …
What is the formula for calculating viscosity?
There are several formulas and equations to calculate viscosity, the most common of which is Viscosity = (2 x (ball density – liquid density) x g x a^2) ÷ (9 x v), where g = acceleration due to gravity = 9.8 m/s^2, a = radius of ball bearing, and v = velocity of ball bearing through liquid.
How does Redwood viscometer work?
The redwood viscometer consist of vertical cylindrical oil cup with an orifice in the centre of its base . A hook pointing upward serve as a guide mark for filling the oil . The cylindrical cup is surrounded by the water bath . The water bath maintain the temperature of the oil to be tested at constant temperature .
What is the principle of the falling ball viscometer?
The Falling Ball Viscometer is based on the measuring principle by Höppler for simple but precise dynamic viscosity measurement of transparent Newtonian fluids. The basic concept is to measure the elapsed time required for the ball to fall under gravity through a sample-filled tube inclined at an angle*.
How is the oscillating piston viscometer used in the laboratory?
The Oscillating Piston Viscometer technology has been adapted for small sample viscosity and micro-sample viscosity testing in laboratory applications. It has also been adapted to measure high pressure viscosity and high temperature viscosity measurements in both laboratory and process environments.
How is the time of fall measured in a viscosity controller?
The time of fall is a measure of viscosity, with the clearance between the piston and inside of the cylinder forming the measuring orifice. The viscosity controller measures the time of fall (Time-of-fall seconds being the measure of viscosity) and displays the resulting viscosity value.
Which is one flow condition does a viscometer measure?
Viscometers only measure under one flow condition. In general, either the fluid remains stationary and an object moves through it, or the object is stationary and the fluid moves past it. The drag caused by relative motion of the fluid and a surface is a measure of the viscosity.
