For the experimental study of heat transfer and pressure drop for Newtonian fluid flow through a pipe, heat transfer and friction factor can be calculated by measuring the fluid inlet and outlet temperatures in addition to the pipe surface temperature and the fluid flow rate and pressure drop along the pipe. For non-Newtonian fluid, are there any additional special considerations?
Although the concept of viscosity is commonly used to characterize a material, it can be inadequate to describe the mechanical behavior of a substance, particularly non-Newtonian fluids. What about non-Newtonian fluid viscosity requirements during experiments?
Well, first of all, keep in mind that the viscosity of non-Newtonian fluids basically changes with flowrate, which should have a direct effect on pressure drop. If the non-Newtonian fluid is time dependent, it would probably exhibit a transient behavior of some sort which would be reflected both in terms of pressure drop and convective heat transfer rate.
Well, first of all, keep in mind that the viscosity of non-Newtonian fluids basically changes with flowrate, which should have a direct effect on pressure drop. If the non-Newtonian fluid is time dependent, it would probably exhibit a transient behavior of some sort which would be reflected both in terms of pressure drop and convective heat transfer rate.
There are plenty of non-Newtonian behaviours. If you require a more specific answer than the one given above you should be more specific yourself about the behaviour of the fluid you want to study. In general their is no additional considerations regarding the experimental method for just one experiment. However it is common that viscosity properties vary with temperature, for example. First thing you need to do is to determine how fluid properties vary with time, temperature, shear stress or degradation.
For my experiments viscosity properties where afected by the preparation method, degradation and temperature, so I had to implement a system to measure those properties on-line.
You can get some idea of special considerations required for the experimental investigation of heat transfer and pressure drop characteristics of non-Newtonian fluids from the following chapters in the Encyclopedia and Handbook. (1) A. V. Shenoy, Natural convection heat transfer to power-law fluids, Handbook of Heat and Mass Transfer, Gulf Publishing Company, Houston, Tx, Vol. 1, Chapter 5, p. 183 (1986). (2) A. V. Shenoy, Natural convection heat transfer to viscoelastic fluids, Encyclopedia of Fluid Mechanics, Gulf Publishing Company, Houston, Tx, Vol. 7, Chapter 10, p. 287 (1988). (3) A. V. Shenoy, Power-law fluid velocity profiles in turbulent pipe flow, Encyclopedia of Fluid Mechanics, Gulf Publishing Company, Houston, Tx, Vol. 1, Chapter 31, p. 1034 (1986). (4) A. V. Shenoy, Turbulent flow velocity profiles in drag-reducing fluids, Encyclopedia of Fluid Mechanics, Gulf Publishing Company, Houston, Tx, Vol. 7, Chapter 16, p. 479 (1988). (5) A. V. Shenoy, Explicit equations for friction factor Reynolds number relation in turbulent flow of power-law fluids through smooth and rough, circular and non-circular pipes, Encyclopedia of Fluid Mechanics, Gulf Publishing Company, Houston, Tx, Supplement 3, Chapter 8, p. 107 (1994).
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