José Carlos Charamba Dutra

Flow Control for Absorption Chillers Using the Par H2O / LiBr Driven in Recirculation Pumps of Low Power

This paper proposes an effective method of variation of speed in the recirculation pump and consequently ensure optimum range of flow for absorption chillers when it uses the pair LiBr/H2O. These systems operate at subatmospheric pressures, merely for this reason the use of non-invasive flow measurement methods. The need for low power recirculation systems in such devices makes it impossible to adopt three-phase loads on the driven of the pumps. These implications prevented the achievement of advances in these systems, limiting the success of important contributions in the literature. Due this, it was designed an experimental apparatus reproducing the flow conditions which are submitted to absorption chillers with LiBr and developed a device that could changing the low power load speeds. It was implemented in LabVIEW language, a PID controller action system, which allowed tested to the flow control, initially for water and then to the saline LiBr/H2O.

Experimental Theoretical Study based on mathematical correlations used in the determination of volume flows of non-intrusive character for lithium bromide solution

This work has as proposed the development of experimental theoretical study based on mathematical correlations able to estimate volume flows of non-intrusive character as functions of diameter and pressure for lithium bromide solution linked to an ultrasonic meter, type transit time, model UFM 170. The experimental bench that gave support to this work has been developed on the premises of the Federal University of Paraíba-UFPB in lab-IES Sustainable Energy Institute and RECOGÁS, Cooperative Research Network North/Northeast Natural Gas. This study was developed in LabVIEW platform, with the help of EES - software (Engineering Equation Solver). This study aims to describe all the positive and negative aspects experienced in the subject of this work in order to contribute with flow measurement techniques non-intrusive that would be applied in absorption refrigeration systems.