Question

The temperature is directly proportional to viscosity.

(a) True

(b) False

The question was posed to me in quiz.

The above asked question is from Factors Affecting Broth Viscosity in chapter Fluid Flow and Mixing of Bioprocess Engineering

Answer 1

Correct choice is (b) False

For explanation I would say: A fluid’s viscosity strongly depends on its temperature. Along with the shear rate, temperature really is the dominating influence. The higher the temperature is, the lower a substance’s viscosity is. Consequently, decreasing temperature causes an increase in viscosity. The relationship between temperature and viscosity is inversely proportional for all substances. A change in temperature always affects the viscosity – it depends on the substance just how much it is influenced by a temperature change. For some fluids a decrease of 1°C already causes a 10 % increase in viscosity.