In this paper, we present comparatively different methods of pressure drop calculation in the gasket plate heat exchangers (PHEs), using correlations recommended in literature on industrial data collected from a vegetable oil refinery. The goal of this study was to compare the results obtained with these correlations, in order to choose one or two for practical purpose of pumping power calculations. We concluded that pressure drop values calculated with Mulley relationship and Buonopane & Troupe correlation were close and also Bond’s equation gave results pretty close to these but the pressure drop is slightly underestimated. Kumar correlation gave results far from all the others and its application will lead to oversize. In conclusion, for further calculations we will chose either the Mulley relationship or the Buonopane & Troupe correlation.
Cristina Amalia Mocanu-Vargancsik and Alina Barbulescu
The purpose of this article is analysing the variability of Buzau river monthly mean discharges, maximum and minimum over time and the impact of Siriu Dam on these discharges. Keeping a stable, moderate variability on the water flow has a significant importance, as this assures normality of life and functionality of the dams. On another hand, the dams are in-built with a range of parameters, decided according to this variability of the discharges. The used data has been collected from Nehoiu and Basca Roziliei hydrometric stations and spans on 55 years, from 1st January 1955 to 31st December 2010. Mid-period, on 30th September 1984, Siriu Dam started operating and the results reveal that its impact on the variability has been moderate on a large time scale. Important changes appear on smaller time scale, as months. The results are supported by graphs drawn in Excel and methods embedded by software.
In this article we analyze the admissibility and the exact observability of a body-beam system when the output is taken in a point of attachment from the beam to the body. The single output case chosen here is the practical measurement of the strength, its velocity or its moment. We prove the exact observability for the moment and the admissibility for the other cases. These results are obtained by the spectral properties of rotating body beam system operator and Ingham's inequalities.