Progress and Trends in Rheology II pp 443-445 | Cite as
Flow of fruit and vegetable purées through pipelines
Abstract
The purpose of this work was to evaluate friction factors in the Darcy-Weisbach equation for the flow of tomato concentrate, sweetened apple purée and apple purée. A pipeline model consisted of a straight horizontal tube 0.02 m in diameter, a sudden expansion and contraction of the tube, a 90° bend, and a valve.
The fluids were classified as non-Newtonian with a yield stress. Pressure drop values for their flow through elements of the pipeline depended on the calculated plug flow radius; friction factor values decreased with increasing flow rates. A correlation between the friction factor and the dry matter content was found; a noticeable influence of the continuous phase viscosity in this phenomenon was suggested.
On the basis of statistical analysis it was concluded that the pressure drop for fruit and vegetable purées flowing through pipelines might be predicted by means of a modified Darcy-Weisbach equation. The Reynolds number is based on apparent viscosity, defined as the ratio of shear stress to shear rate at a given flow rate of the fluid through the pipeline.
Key words
Friction factor Pipeline tomato concentrate fruit puréePreview
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References
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