Permanent Pressure Drop Measurements in Converging-Diverging Plain Annuli.

Document Type : Research Studies

Author

College of Engineering, Mansoura University, Mansoura, Egypt.

Abstract

This paper presents the results of a series of experiments on the measurements of pressure losses for turbulent water flow (Re>10,000) in convergent divergent plain annuli. Depending upon the convergence angle and the divergence angle four different annuli were studied. From, these experiments, generalized empirical correlations were deduced to describe pressure losses for turbulent water flow in the convergent portion, in the divergent portion and in the whole annuli. These correlate the experimental data within ± 4%. In general pressure losses for convergent-divergent plain annuli were found to be functions of both the convergence angle and the divergence angle. Two exceptions were noted from this general rule, when the divergence angle was greater than 10 degrees and the convergence angle was equal to or greater than 7.5 degrees, pressure loss over the whole annulus was function of the divergence angle only. The other expception was when the divergence angle was about 3.5 degrees, pressure loss over the divergent portion took a certain value irrespective the value of the convergence angle.

Main Subjects