Author
Pinkus, Oscar
Other Contributors
Date Issued
1951-06
Subject
Mechanical engineering
Degree
MS;
Terms of Use
This electronic version is a licensed copy owned by Rensselaer Polytechnic Institute, Troy, NY. Copyright of original work retained by author.;
Abstract
It was found that the presence of the solid phase causes an appreciable pressure loss in the pipe. This pressure loss is a linear function of both, solid and gas flow rate. This justified the theoretical equations which predicted such a relationship.; Recommendations for further investigation are made.; Following results of this work it would seem desirable to operate pneumatic systems at low gas velocities and high solid rates. However upper and lower limits were found to exist in such an attempt. At very low solids rates instability sets in followed by strong pressure surges. At high solids rates a settling tendency was observed with nonuniformity in the flow; On the basis of this investigation it is concluded that the drag coefficient C is a function of Reynolds number and is independent of the behavior of the fluid. The ratio of solids velocity to the a velocity is 0.5 - 0.6 for the small sand and 0.3 for the large sand.; Experiments vd.th the two sizes of sand showed a higher pressure drop for the larger particles, other conditions being equal. The solids velocity was lower for the larger diameter. These experiments, however, question the validity of using the Fanning equation in its application to a solid phase. The equation holds for a given solid but does not take into account variations in its size. The introduction of the dimensionless group d/D is proposed; With the object of studying the characteristics of the horizontal flow of a mixture of solids and air a theoretical analysis of the flow pattern was attempted. Experiments were performed whose object was, first, to deter.mine the relationship between pressure loss, solids flow rate and air velocity, and secondly to obtain values for frictional constants involved in the analysis. A justification for the developed equations was sought.; A limitation in this work was the inability to measure directly the solids velocity. Equations were developed for this purpose. Two sizes of the same kind of sand were used.;
Description
June 1951; School of Engineering
Department
Dept. of Mechanical Engineering;
Publisher
Rensselaer Polytechnic Institute, Troy, NY
Relationships
Rensselaer Theses and Dissertations Online Collection;
Access
Restricted to current Rensselaer faculty, staff and students. Access inquiries may be directed to the Rensselaer Libraries.;
