Simulation of moisture alarm for district heating networks

Abstract

Consulta en la Biblioteca ETSI Industriales (Riunet)

[EN] This master thesis hopes to be a first approach in the study of the moisture control of the district heating networks. Nowadays the moisture control is based on the resistance value analysis and the time-domain reflectometer usage. These two technic has been proved to be an effective combination in order to detect and localize leakages in the networks. Despite this fact, there is not a wide knowledge about the actual behaviour of this system and the influence of different factors to the system, such as the differentiation between internal and external leakage, the control of the time influence in the system or the external condition influence in control. In order to increase the knowledge of theses two systems and their relation with the system variables, different tests were developed. These tests can be divided into two main groups; the first ones were related with the moisture alarm behaviour in different moisture conditions (related with time, volume and dimensions) while the second group was related with the pipe isolation water absorption for different salt concentrations. The combination of these tests have made the perception of the importance of the time control in the moisture alarm possible due to the facts that the moisture is transferred through the isolation with low speed ratios and that the moisture alarm has showed some limitations. At the same time the study of the alarm reaction to different moisture states has shown a relation between the moisture conditions and alarm results. These results make the idea of a future better knowledge of the network real state based on the time control, the variables study and the moisture alarm reaction possible. But in order to be able to reach this knowledge, some other studies and tests related with the moisture alarm are needed.