Edward S. Gaddis

Pressure drop on the shell side of shell-and-tube heat exchangers with segmental baffles

Abstract A procedure is presented for evaluating the shell side pressure drop in shell-and-tube heat exchangers with segmental baffles. The procedure is based on correlations for calculating the pressure drop in an ideal tube bank coupled with correction factors, which take into account the influence of leakage and bypass streams, and on equations for calculating the pressure drop in a window section from the Delaware method. The proposed equations were checked by comparing experimental measurements available in the literature with the theoretical predictions. The ranges of the geometrical and operational parameters, for which the deviations between the experimental measurements and the theoretical predictions were within ± 35%, are presented in the paper

Gas Holdup in an Impinging-Stream Reactor

In this work, correlations for predicting the mean gas holdup in the impinging stream reactor are presented. To develop these correlations, measurement with water and air were carried out in two geometrically similar reactors of different size. In addition, the radial distribution of the local gas holdup in a plane of the main tube of both reactors was measured.

A simple method for measuring the gas holdup in two-phase flows

An insight in mixing and in mass transfer processes in gas-liquid flows requires a reliable knowledge of the local gas holdup. Conventional methods for measuring the local gas holdup have shortcomings, such as costly measurement techniques, extensive signal processing, and limitations to highly turbulent flows. In this work, a simple and reliable method for measuring the local gas holdup in turbulent and highly turbulent churn flows is described. It was used to determine the local gas holdup in different locations inside an impinging-stream reactor aerated from the bottom.