Dynamic viscosity, also known as absolute viscosity, measures a fluid's internal resistance to flow when subjected to an external shear stress. In engineering, the Centipoise (cP) and the Poise (P) are the standard units derived from the CGS (centimeter-gram-second) system.
Centipoise (cP): A common unit used in industrial applications, particularly for liquids like water, which has a viscosity of approximately 1 cP at 20°C.
Poise (P): The base CGS unit of dynamic viscosity, named after Jean Léonard Marie Poiseuille. One Poise is equivalent to 1 dyne-second per square centimeter.
The relationship between these units is defined by the metric prefix 'centi-', meaning one-hundredth. Therefore, the conversion factor is defined as \(1 \text{ cP} = 0.01 \text{ P}\). Engineers frequently use these units when specifying lubricant grades, chemical processing parameters, and fluid transport requirements.
Centipoise to Poise Conversion Reference Table
Centipoise (cP)
Poise (P)
0.1
0.001
0.5
0.005
1.0
0.01
2.0
0.02
5.0
0.05
10.0
0.1
20.0
0.2
50.0
0.5
100.0
1
500.0
5
1000.0
10
Conversion Example: 10 cP to Poise
To convert a value from Centipoise to Poise, multiply the value by 0.01. Follow these steps:
Centipoise is preferred in industrial settings because most common fluids, such as water, oils, and solvents, have viscosity values in the range of 1 to 1000 cP. Using cP allows engineers to work with whole numbers rather than small decimals, reducing the risk of calculation errors.
The SI unit for dynamic viscosity is the Pascal-second (Pa·s). The conversion is 1 cP = 0.001 Pa·s. Since 1 P = 0.1 Pa·s, the relationship remains consistent across both CGS and SI systems.
"On fait la science avec des faits, comme on fait une maison avec des pierres ; mais une accumulation de faits n'est pas plus une science qu'un tas de pierres n'est une maison." "Science is built up of facts, as a house is built of stones; but an accumulation of facts is no more a science than a heap of stones is a house." — Henri Poincaré (French Mathematician, Theoretical Physicist & Mining Engineer)