|
|
||||||||
New York State College of Agriculture and Life Sciences, Department of Agricultural Engineering, Cornell University, Ithaca, NY 14853
ABSTRACT
To verify various theoretical and practical aspects of milk flow, an experimental milk pipeline was used. Flow instability, characterized by a flooded section of pipeline (that is, formation of milk "slugs"), was dependent on pipeline configuration. Vacuum fluctuations from milk slugs as great fill depths characterized a looped configuration as 28.6 kPa were measured in a dead-end configuration. By contrast, stable flow over a wide range of flow rates, slopes, and. Manning's equation under stable flow conditions accurately predicted flow rate as a function of fill depth, slope, and pipe diameter. Milk Acid Degree Value was higher in milk subjected to slugging. An analysis of effective shear stress on milk suggests a range of fill depths for which milk quality might be maintained. A theoretical model is presented to predict pipeline milk flow as a function of number of cows and rate of unit attaching. A method for pipeline sizing is presented using this model, together with Manning's equation and suitable constraints for fill depth. Current recommendations for pipeline sizing may result in oversized pipeline diameters.
1 Department of Agricultural Engineering, Technion (Israel Institute of Technology), Haifa 32000, Israel.
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |