Viscosity Converter

About Dynamic Viscosity

Dynamic viscosity is the internal resistance of a fluid to flow. Dynamic viscosity describes the thickness or stickiness of a fluid and is a critical parameter in fluid dynamics as well as in engineering processes.

• Pa·s – SI unit of dynamic viscosity.
• mPa·s – Laboratory common usage; 1 mPa·s = 1 cP.
• Poise (P) – CGS unit; 1 P = 0.1 Pa·s.
• Centipoise (cP) – Used quite often in industry; 1 cP = 0.001 Pa·s.
• dyn·s/cm² – CGS equivalent of poise.

Viscosity Units

Viscosity is the measure of a fluid's resistance to deformation or flow. It is a significant quantity in applications such as fluid dynamics, chemical engineering, and lubrication science. Accurate measurement of viscosity is significant in industrial processes as well as scientific research. The following is the account of the most prevalent units used in the expression of dynamic viscosity on various measurement systems.

SI-Based Units

• Pascal second (Pa·s): The Pascal second is the SI unit of dynamic viscosity. One Pascal second is equivalent to one newton-second per square meter. This unit is widely used in physics and engineering communities where precise viscosity data is required to carry out simulation and analysis.
• Millipascal second (mPa·s): Since the Pascal second can represent reasonably sized values of viscosity, the millipascal second is often used in its stead. It is one-thousandth of a Pa·s (1 mPa·s = 0.001 Pa·s) and is satisfactory for everyday liquids like water, oils, and syrups. Water at 20°C, for example, will have a viscosity of about 1 mPa·s.
• Newton second per square meter (N·s/m²): This unit is unitarily equivalent to the Pascal second (1 N·s/m² = 1 Pa·s), but sometimes shows up in literature or industries with the force and area components spoken out.

CGS (Centimeter–Gram–Second) Units

• Poise (P): The Poise is the CGS unit of dynamic viscosity. One poise is the viscosity at which a velocity difference of one centimeter per second is established between two parallel layers of fluid one centimeter apart when the force is one dyne per square centimeter. It is chiefly used in older literature or when using older standards.
• Centipoise (cP): Much less common than the contemporary poise, the centipoise is 1/100 of a poise (1 P = 100 cP). It is also equal to 1 mPa·s, and hence interchangeably usable in practice. Motor oil, for example, can be between 100 and 400 cP by grade and temperature.
• Dyne second per square centimeter (dyn·s/cm²): Another unit of CGS, this is the official definition of poise in base units of CGS. It imposes the interrelation between force (dyne), time (second), and area (cm²), and is defined as 1 poise.

Conclusion

It is important to know the units of viscosity when dealing with different scientific and engineering systems. Whether employing Pa·s in contemporary fluid dynamics, mPa·s in everyday laboratory practice, or cP for conformity to industry requirements, the ability to convert and utilize these units for precise control and fluid behavior analysis matters.