Experimental Study of Flow Characteristics of Mobile Fans under Real Operating Conditions (Case Study)

Abstract

Cel: The aim of this article is to evaluate the effect of selected positioning parameters of the fan (positioning distance and impeller angle) on the ability to pump a volumetric airflow stream through a construction object. Projekt i metody: Mobilne wentylatory wykorzystywane podczas działań ratowniczych stanowią ważne narzędzie pozwalające ograniczyć rozprzestrzenianie się dymu podczas pożarów wewnętrznych obiektów budowlanych. Z uwagi na charakter wykorzystania tych urządzeń, cechy warunkujące ich skuteczność działania powinny być poddane badaniom z wykorzystaniem metodyk badawczych o charakterystyce zbliżonej do ich rzeczywistych warunków stosowania. W artykule przedstawiono autorską metodę badań objętościowego strumienia przepływu powietrza. Ponadto zaprezentowane zostało stanowisko badawcze FRC (ang. flow resisting curtain) przeznaczone do wyznaczania charakterystyk przepływowych w rzeczywistych układach obiektów budowlanych. Badania przepływowe wykonano na terenie obiektu o kubaturze 282 m3 stanowiącego salę szkoleniową Centrum Naukowo- -Badawczego Ochrony Przeciwpożarowej – Państwowego Instytutu Badawczego. Metodologia: Mobile fans used during rescue operations are an important tool to reduce the spread of smoke during interior fires in buildings. Due to the nature of the use of these devices, the characteristics that determine their performance should be tested using test methodologies with characteristics similar to their actual conditions of use. The article presents the author's method for studying the volumetric flow rate of air. In addition, a flow resisting curtain (FRC) test stand for determining flow characteristics in real building systems was presented. The flow tests were carried out at a facility with a volume of 282 m3, which is a training room of the Scientific and Research Centre for Fire Protection – National Research Institute. Wyniki: As part of the performed research, the flow characteristics for the mobile fan sample were determined. The completed tests showed that the fan pumped a volumetric flow rate ranging from 2471 to 17997 m3/h. It was determined that the most favourable positioning distance of the tested fan calculated from the inlet opening to the room is 5 meters. At this distance, the highest values of volumetric flow rate were obtained for both studied slope angles – 0 and 8° (recorded values are 17298 and 17997 m3/h, respectively). Wnioski: Proper positioning of the mobile fan has a significant impact on the amount of airflow pumped through the building. The positioning parameters of the mobile unit are, respectively, the mechanism for changing the angle of the air supply and its mobility – the ability to move to another location. This article presents the results of a test of the volumetric flow characteristics of an air jet generated by a mobile fan. The test results showed that the parameters of fan positioning have a significant impact on the effectiveness of tactical mechanical ventilation during rescue operations. Observations made during the tests indicate that it is reasonable to implement requirements for the mandatory use of information boards showing the optimal positioning parameters for mobile units to achieve the highest possible expenditure. Słowa kluczowe: Positive Pressure Ventilator (PPV), mobile fan, full scale experiment, open flow, air flow rate