Qualitative Features of Heat Transfer in Highly Viscous Liquids

Qualitative Features of Heat Transfer in Highly Viscous Liquids 

Dissipative heating in highly viscous liquids leads to a considerable rise in temperature even at moderate velocities of motion. For example, according to Table 5.3 (according to [427, 487]), the viscosity and the thermal conductivity coefficient of motor oil at indoor temperature (Ts = 20° C) are, respectively, fi = 0.8kg/(m s) and x = 0.15N/(s K). By substituting these values into (5.8.4), we obtain 

the rise in the oil temperature is so large that one must take account 

For highly viscous liquids (such as glycerin), an exponential dependence of viscosity on temperature is usually assumed [52, 133, 253]  

The temperature distribution in the tube for a nonisothermal flow of a liquid in the case an exponential dependence of viscosity on temperature (5.8.5) has the form [52] 

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